Merge branch 'main' into user-friendly-error-handling

2026-02-06 08:53:41 +00:00 · 2025-09-09 10:21:08 +09:00 · 2025-08-25 10:12:02 +09:00 · 2025-08-24 10:37:37 +09:00 · 2025-08-23 13:04:06 +09:00
136 changed files with 3313 additions and 8426 deletions
--- a/.github/workflows/rust-ci.yml
+++ b/.github/workflows/rust-ci.yml
@@ -62,8 +62,6 @@ jobs:
          components: rustfmt
      - name: cargo fmt
        run: cargo fmt -- --config imports_granularity=Item --check
-      - name: Verify codegen for mcp-types
-        run: ./mcp-types/check_lib_rs.py

  cargo_shear:
    name: cargo shear
@@ -76,7 +74,7 @@ jobs:
    steps:
      - uses: actions/checkout@v5
      - uses: dtolnay/rust-toolchain@1.89
-      - uses: taiki-e/install-action@0c5db7f7f897c03b771660e91d065338615679f4 # v2
+      - uses: taiki-e/install-action@v2
        with:
          tool: cargo-shear
          version: 1.5.1
@@ -180,17 +178,12 @@ jobs:
          find . -name Cargo.toml -mindepth 2 -maxdepth 2 -print0 \
            | xargs -0 -n1 -I{} bash -c 'cd "$(dirname "{}")" && cargo check --profile ${{ matrix.profile }}'

-      - uses: taiki-e/install-action@0c5db7f7f897c03b771660e91d065338615679f4 # v2
-        with:
-          tool: nextest
-          version: 0.9.103
-
-      - name: tests
+      - name: cargo test
        id: test
-        # Tests take too long for release builds to run them on every PR.
+        # `cargo test` takes too long for release builds to run them on every PR
        if: ${{ matrix.profile != 'release' }}
        continue-on-error: true
-        run: cargo nextest run --all-features --no-fail-fast --target ${{ matrix.target }}
+        run: cargo test --all-features --target ${{ matrix.target }} --profile ${{ matrix.profile }}
        env:
          RUST_BACKTRACE: 1

--- a/.github/workflows/rust-release.yml
+++ b/.github/workflows/rust-release.yml
@@ -219,22 +219,3 @@ jobs:
        with:
          tag: ${{ github.ref_name }}
          config: .github/dotslash-config.json
-
-  update-branch:
-    name: Update latest-alpha-cli branch
-    permissions:
-      contents: write
-    needs: release
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Update latest-alpha-cli branch
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
-          set -euo pipefail
-          gh api \
-            repos/${GITHUB_REPOSITORY}/git/refs/heads/latest-alpha-cli \
-            -X PATCH \
-            -f sha="${GITHUB_SHA}" \
-            -F force=true
--- a/README.md
+++ b/README.md
@@ -2,10 +2,7 @@

 <p align="center"><code>npm i -g @openai/codex</code><br />or <code>brew install codex</code></p>

-<p align="center"><strong>Codex CLI</strong> is a coding agent from OpenAI that runs locally on your computer.
-</br>
-</br>If you want Codex in your code editor (VS Code, Cursor, Windsurf), <a href="https://developers.openai.com/codex/ide">install in your IDE</a>
-</br>If you are looking for the <em>cloud-based agent</em> from OpenAI, <strong>Codex Web</strong>, go to <a href="https://chatgpt.com/codex">chatgpt.com/codex</a></p>
+<p align="center"><strong>Codex CLI</strong> is a coding agent from OpenAI that runs locally on your computer.</br>If you are looking for the <em>cloud-based agent</em> from OpenAI, <strong>Codex Web</strong>, see <a href="https://chatgpt.com/codex">chatgpt.com/codex</a>.</p>

 <p align="center">
  <img src="./.github/codex-cli-splash.png" alt="Codex CLI splash" width="80%" />
--- a/codex-rs/Cargo.lock
+++ b/codex-rs/Cargo.lock
@@ -311,6 +311,15 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3a8241f3ebb85c056b509d4327ad0358fbbba6ffb340bf388f26350aeda225b1"

+[[package]]
+name = "bincode"
+version = "1.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1f45e9417d87227c7a56d22e471c6206462cba514c7590c09aff4cf6d1ddcad"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "bit-set"
 version = "0.5.3"
@@ -561,6 +570,7 @@ dependencies = [
 "clap",
 "codex-common",
 "codex-core",
+ "codex-protocol",
 "serde",
 "serde_json",
 "tempfile",
@@ -645,7 +655,7 @@ dependencies = [
 "tokio-test",
 "tokio-util",
 "toml",
- "toml_edit",
+ "toml_edit 0.23.4",
 "tracing",
 "tree-sitter",
 "tree-sitter-bash",
@@ -768,7 +778,6 @@ version = "0.0.0"
 dependencies = [
 "anyhow",
 "assert_cmd",
- "base64",
 "codex-arg0",
 "codex-common",
 "codex-core",
@@ -776,7 +785,6 @@ dependencies = [
 "codex-protocol",
 "mcp-types",
 "mcp_test_support",
- "os_info",
 "pretty_assertions",
 "schemars 0.8.22",
 "serde",
@@ -822,7 +830,6 @@ dependencies = [
 "strum 0.27.2",
 "strum_macros 0.27.2",
 "sys-locale",
- "tempfile",
 "tracing",
 "ts-rs",
 "uuid",
@@ -835,7 +842,6 @@ dependencies = [
 "anyhow",
 "clap",
 "codex-protocol",
- "mcp-types",
 "ts-rs",
 ]

@@ -870,7 +876,6 @@ dependencies = [
 "path-clean",
 "pathdiff",
 "pretty_assertions",
- "pulldown-cmark",
 "rand 0.9.2",
 "ratatui",
 "regex-lite",
@@ -887,6 +892,7 @@ dependencies = [
 "tracing",
 "tracing-appender",
 "tracing-subscriber",
+ "tui-markdown",
 "unicode-segmentation",
 "unicode-width 0.1.14",
 "url",
@@ -1754,6 +1760,12 @@ version = "0.3.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f90f7dce0722e95104fcb095585910c0977252f286e354b5e3bd38902cd99988"

+[[package]]
+name = "futures-timer"
+version = "3.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f288b0a4f20f9a56b5d1da57e2227c661b7b16168e2f72365f57b63326e29b24"
+
 [[package]]
 name = "futures-util"
 version = "0.3.31"
@@ -1839,6 +1851,12 @@ version = "0.31.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "07e28edb80900c19c28f1072f2e8aeca7fa06b23cd4169cefe1af5aa3260783f"

+[[package]]
+name = "glob"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8d1add55171497b4705a648c6b583acafb01d58050a51727785f0b2c8e0a2b2"
+
 [[package]]
 name = "globset"
 version = "0.4.16"
@@ -2546,6 +2564,12 @@ dependencies = [
 "libc",
 ]

+[[package]]
+name = "linked-hash-map"
+version = "0.5.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0717cef1bc8b636c6e1c1bbdefc09e6322da8a9321966e8928ef80d20f7f770f"
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.4.15"
@@ -2655,11 +2679,9 @@ version = "0.0.0"
 dependencies = [
 "anyhow",
 "assert_cmd",
- "codex-core",
 "codex-mcp-server",
 "codex-protocol",
 "mcp-types",
- "os_info",
 "pretty_assertions",
 "serde",
 "serde_json",
@@ -2987,6 +3009,28 @@ version = "1.70.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a4895175b425cb1f87721b59f0f286c2092bd4af812243672510e1ac53e2e0ad"

+[[package]]
+name = "onig"
+version = "6.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "336b9c63443aceef14bea841b899035ae3abe89b7c486aaf4c5bd8aafedac3f0"
+dependencies = [
+ "bitflags 2.9.1",
+ "libc",
+ "once_cell",
+ "onig_sys",
+]
+
+[[package]]
+name = "onig_sys"
+version = "69.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c7f86c6eef3d6df15f23bcfb6af487cbd2fed4e5581d58d5bf1f5f8b7f6727dc"
+dependencies = [
+ "cc",
+ "pkg-config",
+]
+
 [[package]]
 name = "openssl"
 version = "0.10.73"
@@ -3312,6 +3356,15 @@ dependencies = [
 "yansi",
 ]

+[[package]]
+name = "proc-macro-crate"
+version = "3.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "edce586971a4dfaa28950c6f18ed55e0406c1ab88bbce2c6f6293a7aaba73d35"
+dependencies = [
+ "toml_edit 0.22.27",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.95"
@@ -3323,9 +3376,9 @@ dependencies = [

 [[package]]
 name = "pulldown-cmark"
-version = "0.10.3"
+version = "0.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "76979bea66e7875e7509c4ec5300112b316af87fa7a252ca91c448b32dfe3993"
+checksum = "1e8bbe1a966bd2f362681a44f6edce3c2310ac21e4d5067a6e7ec396297a6ea0"
 dependencies = [
 "bitflags 2.9.1",
 "getopts",
@@ -3336,9 +3389,9 @@ dependencies = [

 [[package]]
 name = "pulldown-cmark-escape"
-version = "0.10.1"
+version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd348ff538bc9caeda7ee8cad2d1d48236a1f443c1fa3913c6a02fe0043b1dd3"
+checksum = "007d8adb5ddab6f8e3f491ac63566a7d5002cc7ed73901f72057943fa71ae1ae"

 [[package]]
 name = "pxfm"
@@ -3569,6 +3622,12 @@ version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"

+[[package]]
+name = "relative-path"
+version = "1.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba39f3699c378cd8970968dcbff9c43159ea4cfbd88d43c00b22f2ef10a435d2"
+
 [[package]]
 name = "reqwest"
 version = "0.12.23"
@@ -3627,12 +3686,51 @@ dependencies = [
 "windows-sys 0.52.0",
 ]

+[[package]]
+name = "rstest"
+version = "0.25.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fc39292f8613e913f7df8fa892b8944ceb47c247b78e1b1ae2f09e019be789d"
+dependencies = [
+ "futures-timer",
+ "futures-util",
+ "rstest_macros",
+ "rustc_version",
+]
+
+[[package]]
+name = "rstest_macros"
+version = "0.25.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1f168d99749d307be9de54d23fd226628d99768225ef08f6ffb52e0182a27746"
+dependencies = [
+ "cfg-if",
+ "glob",
+ "proc-macro-crate",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "relative-path",
+ "rustc_version",
+ "syn 2.0.104",
+ "unicode-ident",
+]
+
 [[package]]
 name = "rustc-demangle"
 version = "0.1.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "989e6739f80c4ad5b13e0fd7fe89531180375b18520cc8c82080e4dc4035b84f"

+[[package]]
+name = "rustc_version"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfcb3a22ef46e85b45de6ee7e79d063319ebb6594faafcf1c225ea92ab6e9b92"
+dependencies = [
+ "semver",
+]
+
 [[package]]
 name = "rustix"
 version = "0.38.44"
@@ -3872,6 +3970,12 @@ dependencies = [
 "libc",
 ]

+[[package]]
+name = "semver"
+version = "1.0.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56e6fa9c48d24d85fb3de5ad847117517440f6beceb7798af16b4a87d616b8d0"
+
 [[package]]
 name = "serde"
 version = "1.0.219"
@@ -4355,6 +4459,28 @@ dependencies = [
 "syn 2.0.104",
 ]

+[[package]]
+name = "syntect"
+version = "5.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "874dcfa363995604333cf947ae9f751ca3af4522c60886774c4963943b4746b1"
+dependencies = [
+ "bincode",
+ "bitflags 1.3.2",
+ "flate2",
+ "fnv",
+ "once_cell",
+ "onig",
+ "plist",
+ "regex-syntax 0.8.5",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "thiserror 1.0.69",
+ "walkdir",
+ "yaml-rust",
+]
+
 [[package]]
 name = "sys-locale"
 version = "0.3.2"
@@ -4678,12 +4804,18 @@ dependencies = [
 "indexmap 2.10.0",
 "serde",
 "serde_spanned",
- "toml_datetime",
+ "toml_datetime 0.7.0",
 "toml_parser",
 "toml_writer",
 "winnow",
 ]

+[[package]]
+name = "toml_datetime"
+version = "0.6.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22cddaf88f4fbc13c51aebbf5f8eceb5c7c5a9da2ac40a13519eb5b0a0e8f11c"
+
 [[package]]
 name = "toml_datetime"
 version = "0.7.0"
@@ -4693,6 +4825,17 @@ dependencies = [
 "serde",
 ]

+[[package]]
+name = "toml_edit"
+version = "0.22.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41fe8c660ae4257887cf66394862d21dbca4a6ddd26f04a3560410406a2f819a"
+dependencies = [
+ "indexmap 2.10.0",
+ "toml_datetime 0.6.11",
+ "winnow",
+]
+
 [[package]]
 name = "toml_edit"
 version = "0.23.4"
@@ -4700,7 +4843,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7211ff1b8f0d3adae1663b7da9ffe396eabe1ca25f0b0bee42b0da29a9ddce93"
 dependencies = [
 "indexmap 2.10.0",
- "toml_datetime",
+ "toml_datetime 0.7.0",
 "toml_parser",
 "toml_writer",
 "winnow",
@@ -4910,6 +5053,22 @@ dependencies = [
 "termcolor",
 ]

+[[package]]
+name = "tui-markdown"
+version = "0.3.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d10648c25931bfaaf5334ff4e7dc5f3d830e0c50d7b0119b1d5cfe771f540536"
+dependencies = [
+ "ansi-to-tui",
+ "itertools 0.14.0",
+ "pretty_assertions",
+ "pulldown-cmark",
+ "ratatui",
+ "rstest",
+ "syntect",
+ "tracing",
+]
+
 [[package]]
 name = "typenum"
 version = "1.18.0"
@@ -5691,6 +5850,15 @@ version = "0.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec107c4503ea0b4a98ef47356329af139c0a4f7750e621cf2973cd3385ebcb3d"

+[[package]]
+name = "yaml-rust"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
+dependencies = [
+ "linked-hash-map",
+]
+
 [[package]]
 name = "yansi"
 version = "1.0.1"
--- a/codex-rs/Cargo.toml
+++ b/codex-rs/Cargo.toml
@@ -34,7 +34,6 @@ rust = {}

 [workspace.lints.clippy]
 expect_used = "deny"
-redundant_clone = "deny"
 uninlined_format_args = "deny"
 unwrap_used = "deny"

--- a/codex-rs/README.md
+++ b/codex-rs/README.md
@@ -35,7 +35,7 @@ npx @modelcontextprotocol/inspector codex mcp

 You can enable notifications by configuring a script that is run whenever the agent finishes a turn. The [notify documentation](../docs/config.md#notify) includes a detailed example that explains how to get desktop notifications via [terminal-notifier](https://github.com/julienXX/terminal-notifier) on macOS.

-### `codex exec` to run Codex programmatically/non-interactively
+### `codex exec` to run Codex programmatially/non-interactively

 To run Codex non-interactively, run `codex exec PROMPT` (you can also pass the prompt via `stdin`) and Codex will work on your task until it decides that it is done and exits. Output is printed to the terminal directly. You can set the `RUST_LOG` environment variable to see more about what's going on.

--- a/codex-rs/apply-patch/src/lib.rs
+++ b/codex-rs/apply-patch/src/lib.rs
@@ -726,15 +726,13 @@ fn compute_replacements(
            line_index = start_idx + pattern.len();
        } else {
            return Err(ApplyPatchError::ComputeReplacements(format!(
-                "Failed to find expected lines in {}:\n{}",
-                path.display(),
-                chunk.old_lines.join("\n"),
+                "Failed to find expected lines {:?} in {}",
+                chunk.old_lines,
+                path.display()
            )));
        }
    }

-    replacements.sort_by(|(lhs_idx, _, _), (rhs_idx, _, _)| lhs_idx.cmp(rhs_idx));
-
    Ok(replacements)
 }

@@ -1218,33 +1216,6 @@ PATCH"#,
        assert_eq!(contents, "a\nB\nc\nd\nE\nf\ng\n");
    }

-    #[test]
-    fn test_pure_addition_chunk_followed_by_removal() {
-        let dir = tempdir().unwrap();
-        let path = dir.path().join("panic.txt");
-        fs::write(&path, "line1\nline2\nline3\n").unwrap();
-        let patch = wrap_patch(&format!(
-            r#"*** Update File: {}
-@@
-+after-context
-+second-line
-@@
- line1
-line2
-line3
-+line2-replacement"#,
-            path.display()
-        ));
-        let mut stdout = Vec::new();
-        let mut stderr = Vec::new();
-        apply_patch(&patch, &mut stdout, &mut stderr).unwrap();
-        let contents = fs::read_to_string(path).unwrap();
-        assert_eq!(
-            contents,
-            "line1\nline2-replacement\nafter-context\nsecond-line\n"
-        );
-    }
-
    /// Ensure that patches authored with ASCII characters can update lines that
    /// contain typographic Unicode punctuation (e.g. EN DASH, NON-BREAKING
    /// HYPHEN). Historically `git apply` succeeds in such scenarios but our
--- a/codex-rs/apply-patch/src/parser.rs
+++ b/codex-rs/apply-patch/src/parser.rs
@@ -617,7 +617,7 @@ fn test_parse_patch_lenient() {
    assert_eq!(
        parse_patch_text(&patch_text_in_double_quoted_heredoc, ParseMode::Lenient),
        Ok(ApplyPatchArgs {
-            hunks: expected_patch,
+            hunks: expected_patch.clone(),
            patch: patch_text.to_string(),
            workdir: None,
        })
@@ -637,7 +637,7 @@ fn test_parse_patch_lenient() {
        "<<EOF\n*** Begin Patch\n*** Update File: file2.py\nEOF\n".to_string();
    assert_eq!(
        parse_patch_text(&patch_text_with_missing_closing_heredoc, ParseMode::Strict),
-        Err(expected_error)
+        Err(expected_error.clone())
    );
    assert_eq!(
        parse_patch_text(&patch_text_with_missing_closing_heredoc, ParseMode::Lenient),
--- a/codex-rs/chatgpt/Cargo.toml
+++ b/codex-rs/chatgpt/Cargo.toml
@@ -11,6 +11,7 @@ anyhow = "1"
 clap = { version = "4", features = ["derive"] }
 codex-common = { path = "../common", features = ["cli"] }
 codex-core = { path = "../core" }
+codex-protocol = { path = "../protocol" }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 tokio = { version = "1", features = ["full"] }
--- a/codex-rs/chatgpt/src/apply_command.rs
+++ b/codex-rs/chatgpt/src/apply_command.rs
@@ -31,7 +31,7 @@ pub async fn run_apply_command(
        ConfigOverrides::default(),
    )?;

-    init_chatgpt_token_from_auth(&config.codex_home).await?;
+    init_chatgpt_token_from_auth(&config.codex_home, &config.responses_originator_header).await?;

    let task_response = get_task(&config, apply_cli.task_id).await?;
    apply_diff_from_task(task_response, cwd).await
--- a/codex-rs/chatgpt/src/chatgpt_client.rs
+++ b/codex-rs/chatgpt/src/chatgpt_client.rs
@@ -13,10 +13,10 @@ pub(crate) async fn chatgpt_get_request<T: DeserializeOwned>(
    path: String,
 ) -> anyhow::Result<T> {
    let chatgpt_base_url = &config.chatgpt_base_url;
-    init_chatgpt_token_from_auth(&config.codex_home).await?;
+    init_chatgpt_token_from_auth(&config.codex_home, &config.responses_originator_header).await?;

    // Make direct HTTP request to ChatGPT backend API with the token
-    let client = create_client();
+    let client = create_client(&config.responses_originator_header);
    let url = format!("{chatgpt_base_url}{path}");

    let token =
--- a/codex-rs/chatgpt/src/chatgpt_token.rs
+++ b/codex-rs/chatgpt/src/chatgpt_token.rs
@@ -1,4 +1,5 @@
 use codex_core::CodexAuth;
+use codex_protocol::mcp_protocol::AuthMode;
 use std::path::Path;
 use std::sync::LazyLock;
 use std::sync::RwLock;
@@ -18,8 +19,11 @@ pub fn set_chatgpt_token_data(value: TokenData) {
 }

 /// Initialize the ChatGPT token from auth.json file
-pub async fn init_chatgpt_token_from_auth(codex_home: &Path) -> std::io::Result<()> {
-    let auth = CodexAuth::from_codex_home(codex_home)?;
+pub async fn init_chatgpt_token_from_auth(
+    codex_home: &Path,
+    originator: &str,
+) -> std::io::Result<()> {
+    let auth = CodexAuth::from_codex_home(codex_home, AuthMode::ChatGPT, originator)?;
    if let Some(auth) = auth {
        let token_data = auth.get_token_data().await?;
        set_chatgpt_token_data(token_data);
--- a/codex-rs/cli/src/login.rs
+++ b/codex-rs/cli/src/login.rs
@@ -1,6 +1,7 @@
 use codex_common::CliConfigOverrides;
 use codex_core::CodexAuth;
 use codex_core::auth::CLIENT_ID;
+use codex_core::auth::OPENAI_API_KEY_ENV_VAR;
 use codex_core::auth::login_with_api_key;
 use codex_core::auth::logout;
 use codex_core::config::Config;
@@ -8,10 +9,11 @@ use codex_core::config::ConfigOverrides;
 use codex_login::ServerOptions;
 use codex_login::run_login_server;
 use codex_protocol::mcp_protocol::AuthMode;
+use std::env;
 use std::path::PathBuf;

-pub async fn login_with_chatgpt(codex_home: PathBuf) -> std::io::Result<()> {
-    let opts = ServerOptions::new(codex_home, CLIENT_ID.to_string());
+pub async fn login_with_chatgpt(codex_home: PathBuf, originator: String) -> std::io::Result<()> {
+    let opts = ServerOptions::new(codex_home, CLIENT_ID.to_string(), originator);
    let server = run_login_server(opts)?;

    eprintln!(
@@ -25,7 +27,12 @@ pub async fn login_with_chatgpt(codex_home: PathBuf) -> std::io::Result<()> {
 pub async fn run_login_with_chatgpt(cli_config_overrides: CliConfigOverrides) -> ! {
    let config = load_config_or_exit(cli_config_overrides);

-    match login_with_chatgpt(config.codex_home).await {
+    match login_with_chatgpt(
+        config.codex_home,
+        config.responses_originator_header.clone(),
+    )
+    .await
+    {
        Ok(_) => {
            eprintln!("Successfully logged in");
            std::process::exit(0);
@@ -58,11 +65,23 @@ pub async fn run_login_with_api_key(
 pub async fn run_login_status(cli_config_overrides: CliConfigOverrides) -> ! {
    let config = load_config_or_exit(cli_config_overrides);

-    match CodexAuth::from_codex_home(&config.codex_home) {
+    match CodexAuth::from_codex_home(
+        &config.codex_home,
+        config.preferred_auth_method,
+        &config.responses_originator_header,
+    ) {
        Ok(Some(auth)) => match auth.mode {
            AuthMode::ApiKey => match auth.get_token().await {
                Ok(api_key) => {
                    eprintln!("Logged in using an API key - {}", safe_format_key(&api_key));
+
+                    if let Ok(env_api_key) = env::var(OPENAI_API_KEY_ENV_VAR)
+                        && env_api_key == api_key
+                    {
+                        eprintln!(
+                            "   API loaded from OPENAI_API_KEY environment variable or .env file"
+                        );
+                    }
                    std::process::exit(0);
                }
                Err(e) => {
--- a/codex-rs/cli/src/proto.rs
+++ b/codex-rs/cli/src/proto.rs
@@ -37,8 +37,11 @@ pub async fn run_main(opts: ProtoCli) -> anyhow::Result<()> {

    let config = Config::load_with_cli_overrides(overrides_vec, ConfigOverrides::default())?;
    // Use conversation_manager API to start a conversation
-    let conversation_manager =
-        ConversationManager::new(AuthManager::shared(config.codex_home.clone()));
+    let conversation_manager = ConversationManager::new(AuthManager::shared(
+        config.codex_home.clone(),
+        config.preferred_auth_method,
+        config.responses_originator_header.clone(),
+    ));
    let NewConversation {
        conversation_id: _,
        conversation,
--- a/codex-rs/common/src/elapsed.rs
+++ b/codex-rs/common/src/elapsed.rs
@@ -2,7 +2,7 @@ use std::time::Duration;
 use std::time::Instant;

 /// Returns a string representing the elapsed time since `start_time` like
-/// "1m 15s" or "1.50s".
+/// "1m15s" or "1.50s".
 pub fn format_elapsed(start_time: Instant) -> String {
    format_duration(start_time.elapsed())
 }
@@ -12,7 +12,7 @@ pub fn format_elapsed(start_time: Instant) -> String {
 /// Formatting rules:
 /// * < 1 s  ->  "{milli}ms"
 /// * < 60 s ->  "{sec:.2}s" (two decimal places)
-/// * >= 60 s ->  "{min}m {sec:02}s"
+/// * >= 60 s ->  "{min}m{sec:02}s"
 pub fn format_duration(duration: Duration) -> String {
    let millis = duration.as_millis() as i64;
    format_elapsed_millis(millis)
@@ -26,7 +26,7 @@ fn format_elapsed_millis(millis: i64) -> String {
    } else {
        let minutes = millis / 60_000;
        let seconds = (millis % 60_000) / 1000;
-        format!("{minutes}m {seconds:02}s")
+        format!("{minutes}m{seconds:02}s")
    }
 }

@@ -61,18 +61,12 @@ mod tests {
    fn test_format_duration_minutes() {
        // Durations ≥ 1 minute should be printed mmss.
        let dur = Duration::from_millis(75_000); // 1m15s
-        assert_eq!(format_duration(dur), "1m 15s");
+        assert_eq!(format_duration(dur), "1m15s");

        let dur_exact = Duration::from_millis(60_000); // 1m0s
-        assert_eq!(format_duration(dur_exact), "1m 00s");
+        assert_eq!(format_duration(dur_exact), "1m00s");

        let dur_long = Duration::from_millis(3_601_000);
-        assert_eq!(format_duration(dur_long), "60m 01s");
-    }
-
-    #[test]
-    fn test_format_duration_one_hour_has_space() {
-        let dur_hour = Duration::from_millis(3_600_000);
-        assert_eq!(format_duration(dur_hour), "60m 00s");
+        assert_eq!(format_duration(dur_long), "60m01s");
    }
 }
--- a/codex-rs/common/src/model_presets.rs
+++ b/codex-rs/common/src/model_presets.rs
@@ -49,13 +49,6 @@ pub fn builtin_model_presets() -> &'static [ModelPreset] {
            model: "gpt-5",
            effort: ReasoningEffort::High,
        },
-        ModelPreset {
-            id: "gpt-5-high-new",
-            label: "gpt-5 high new",
-            description: "— our latest release tuned to rely on the model's built-in reasoning defaults",
-            model: "gpt-5-high-new",
-            effort: ReasoningEffort::Medium,
-        },
    ];
    PRESETS
 }
--- a/codex-rs/core/Cargo.toml
+++ b/codex-rs/core/Cargo.toml
@@ -54,7 +54,6 @@ tracing = { version = "0.1.41", features = ["log"] }
 tree-sitter = "0.25.9"
 tree-sitter-bash = "0.25.0"
 uuid = { version = "1", features = ["serde", "v4"] }
-which = "6"
 wildmatch = "2.4.0"


@@ -70,6 +69,9 @@ openssl-sys = { version = "*", features = ["vendored"] }
 [target.aarch64-unknown-linux-musl.dependencies]
 openssl-sys = { version = "*", features = ["vendored"] }

+[target.'cfg(target_os = "windows")'.dependencies]
+which = "6"
+
 [dev-dependencies]
 assert_cmd = "2"
 core_test_support = { path = "tests/common" }
--- a/codex-rs/core/src/auth.rs
+++ b/codex-rs/core/src/auth.rs
@@ -17,7 +17,6 @@ use std::time::Duration;

 use codex_protocol::mcp_protocol::AuthMode;

-use crate::token_data::PlanType;
 use crate::token_data::TokenData;
 use crate::token_data::parse_id_token;

@@ -71,9 +70,14 @@ impl CodexAuth {
        Ok(access)
    }

-    /// Loads the available auth information from the auth.json.
-    pub fn from_codex_home(codex_home: &Path) -> std::io::Result<Option<CodexAuth>> {
-        load_auth(codex_home)
+    /// Loads the available auth information from the auth.json or
+    /// OPENAI_API_KEY environment variable.
+    pub fn from_codex_home(
+        codex_home: &Path,
+        preferred_auth_method: AuthMode,
+        originator: &str,
+    ) -> std::io::Result<Option<CodexAuth>> {
+        load_auth(codex_home, true, preferred_auth_method, originator)
    }

    pub async fn get_token_data(&self) -> Result<TokenData, std::io::Error> {
@@ -132,12 +136,13 @@ impl CodexAuth {
    }

    pub fn get_account_id(&self) -> Option<String> {
-        self.get_current_token_data().and_then(|t| t.account_id)
+        self.get_current_token_data()
+            .and_then(|t| t.account_id.clone())
    }

-    pub(crate) fn get_plan_type(&self) -> Option<PlanType> {
+    pub fn get_plan_type(&self) -> Option<String> {
        self.get_current_token_data()
-            .and_then(|t| t.id_token.chatgpt_plan_type)
+            .and_then(|t| t.id_token.chatgpt_plan_type.as_ref().map(|p| p.as_string()))
    }

    fn get_current_auth_json(&self) -> Option<AuthDotJson> {
@@ -146,7 +151,7 @@ impl CodexAuth {
    }

    fn get_current_token_data(&self) -> Option<TokenData> {
-        self.get_current_auth_json().and_then(|t| t.tokens)
+        self.get_current_auth_json().and_then(|t| t.tokens.clone())
    }

    /// Consider this private to integration tests.
@@ -168,7 +173,7 @@ impl CodexAuth {
            mode: AuthMode::ChatGPT,
            auth_file: PathBuf::new(),
            auth_dot_json,
-            client: crate::default_client::create_client(),
+            client: crate::default_client::create_client("codex_cli_rs"),
        }
    }

@@ -183,17 +188,19 @@ impl CodexAuth {
    }

    pub fn from_api_key(api_key: &str) -> Self {
-        Self::from_api_key_with_client(api_key, crate::default_client::create_client())
+        Self::from_api_key_with_client(
+            api_key,
+            crate::default_client::create_client(crate::default_client::DEFAULT_ORIGINATOR),
+        )
    }
 }

 pub const OPENAI_API_KEY_ENV_VAR: &str = "OPENAI_API_KEY";

-pub fn read_openai_api_key_from_env() -> Option<String> {
+fn read_openai_api_key_from_env() -> Option<String> {
    env::var(OPENAI_API_KEY_ENV_VAR)
        .ok()
-        .map(|value| value.trim().to_string())
-        .filter(|value| !value.is_empty())
+        .filter(|s| !s.is_empty())
 }

 pub fn get_auth_file(codex_home: &Path) -> PathBuf {
@@ -211,7 +218,7 @@ pub fn logout(codex_home: &Path) -> std::io::Result<bool> {
    }
 }

-/// Writes an `auth.json` that contains only the API key.
+/// Writes an `auth.json` that contains only the API key. Intended for CLI use.
 pub fn login_with_api_key(codex_home: &Path, api_key: &str) -> std::io::Result<()> {
    let auth_dot_json = AuthDotJson {
        openai_api_key: Some(api_key.to_string()),
@@ -221,11 +228,29 @@ pub fn login_with_api_key(codex_home: &Path, api_key: &str) -> std::io::Result<(
    write_auth_json(&get_auth_file(codex_home), &auth_dot_json)
 }

-fn load_auth(codex_home: &Path) -> std::io::Result<Option<CodexAuth>> {
+fn load_auth(
+    codex_home: &Path,
+    include_env_var: bool,
+    preferred_auth_method: AuthMode,
+    originator: &str,
+) -> std::io::Result<Option<CodexAuth>> {
+    // First, check to see if there is a valid auth.json file. If not, we fall
+    // back to AuthMode::ApiKey using the OPENAI_API_KEY environment variable
+    // (if it is set).
    let auth_file = get_auth_file(codex_home);
-    let client = crate::default_client::create_client();
+    let client = crate::default_client::create_client(originator);
    let auth_dot_json = match try_read_auth_json(&auth_file) {
        Ok(auth) => auth,
+        // If auth.json does not exist, try to read the OPENAI_API_KEY from the
+        // environment variable.
+        Err(e) if e.kind() == std::io::ErrorKind::NotFound && include_env_var => {
+            return match read_openai_api_key_from_env() {
+                Some(api_key) => Ok(Some(CodexAuth::from_api_key_with_client(&api_key, client))),
+                None => Ok(None),
+            };
+        }
+        // Though if auth.json exists but is malformed, do not fall back to the
+        // env var because the user may be expecting to use AuthMode::ChatGPT.
        Err(e) => {
            return Err(e);
        }
@@ -237,11 +262,32 @@ fn load_auth(codex_home: &Path) -> std::io::Result<Option<CodexAuth>> {
        last_refresh,
    } = auth_dot_json;

-    // Prefer AuthMode.ApiKey if it's set in the auth.json.
+    // If the auth.json has an API key AND does not appear to be on a plan that
+    // should prefer AuthMode::ChatGPT, use AuthMode::ApiKey.
    if let Some(api_key) = &auth_json_api_key {
-        return Ok(Some(CodexAuth::from_api_key_with_client(api_key, client)));
+        // Should any of these be AuthMode::ChatGPT with the api_key set?
+        // Does AuthMode::ChatGPT indicate that there is an auth.json that is
+        // "refreshable" even if we are using the API key for auth?
+        match &tokens {
+            Some(tokens) => {
+                if tokens.should_use_api_key(preferred_auth_method, tokens.is_openai_email()) {
+                    return Ok(Some(CodexAuth::from_api_key_with_client(api_key, client)));
+                } else {
+                    // Ignore the API key and fall through to ChatGPT auth.
+                }
+            }
+            None => {
+                // We have an API key but no tokens in the auth.json file.
+                // Perhaps the user ran `codex login --api-key <KEY>` or updated
+                // auth.json by hand. Either way, let's assume they are trying
+                // to use their API key.
+                return Ok(Some(CodexAuth::from_api_key_with_client(api_key, client)));
+            }
+        }
    }

+    // For the AuthMode::ChatGPT variant, perhaps neither api_key nor
+    // openai_api_key should exist?
    Ok(Some(CodexAuth {
        api_key: None,
        mode: AuthMode::ChatGPT,
@@ -291,10 +337,10 @@ async fn update_tokens(
    let tokens = auth_dot_json.tokens.get_or_insert_with(TokenData::default);
    tokens.id_token = parse_id_token(&id_token).map_err(std::io::Error::other)?;
    if let Some(access_token) = access_token {
-        tokens.access_token = access_token;
+        tokens.access_token = access_token.to_string();
    }
    if let Some(refresh_token) = refresh_token {
-        tokens.refresh_token = refresh_token;
+        tokens.refresh_token = refresh_token.to_string();
    }
    auth_dot_json.last_refresh = Some(Utc::now());
    write_auth_json(auth_file, &auth_dot_json)?;
@@ -371,6 +417,7 @@ use std::sync::RwLock;
 /// Internal cached auth state.
 #[derive(Clone, Debug)]
 struct CachedAuth {
+    preferred_auth_mode: AuthMode,
    auth: Option<CodexAuth>,
 }

@@ -426,7 +473,9 @@ mod tests {
            auth_dot_json,
            auth_file: _,
            ..
-        } = super::load_auth(codex_home.path()).unwrap().unwrap();
+        } = super::load_auth(codex_home.path(), false, AuthMode::ChatGPT, "codex_cli_rs")
+            .unwrap()
+            .unwrap();
        assert_eq!(None, api_key);
        assert_eq!(AuthMode::ChatGPT, mode);

@@ -455,6 +504,88 @@ mod tests {
        )
    }

+    /// Even if the OPENAI_API_KEY is set in auth.json, if the plan is not in
+    /// [`TokenData::is_plan_that_should_use_api_key`], it should use
+    /// [`AuthMode::ChatGPT`].
+    #[tokio::test]
+    async fn pro_account_with_api_key_still_uses_chatgpt_auth() {
+        let codex_home = tempdir().unwrap();
+        let fake_jwt = write_auth_file(
+            AuthFileParams {
+                openai_api_key: Some("sk-test-key".to_string()),
+                chatgpt_plan_type: "pro".to_string(),
+            },
+            codex_home.path(),
+        )
+        .expect("failed to write auth file");
+
+        let CodexAuth {
+            api_key,
+            mode,
+            auth_dot_json,
+            auth_file: _,
+            ..
+        } = super::load_auth(codex_home.path(), false, AuthMode::ChatGPT, "codex_cli_rs")
+            .unwrap()
+            .unwrap();
+        assert_eq!(None, api_key);
+        assert_eq!(AuthMode::ChatGPT, mode);
+
+        let guard = auth_dot_json.lock().unwrap();
+        let auth_dot_json = guard.as_ref().expect("AuthDotJson should exist");
+        assert_eq!(
+            &AuthDotJson {
+                openai_api_key: None,
+                tokens: Some(TokenData {
+                    id_token: IdTokenInfo {
+                        email: Some("user@example.com".to_string()),
+                        chatgpt_plan_type: Some(PlanType::Known(KnownPlan::Pro)),
+                        raw_jwt: fake_jwt,
+                    },
+                    access_token: "test-access-token".to_string(),
+                    refresh_token: "test-refresh-token".to_string(),
+                    account_id: None,
+                }),
+                last_refresh: Some(
+                    DateTime::parse_from_rfc3339(LAST_REFRESH)
+                        .unwrap()
+                        .with_timezone(&Utc)
+                ),
+            },
+            auth_dot_json
+        )
+    }
+
+    /// If the OPENAI_API_KEY is set in auth.json and it is an enterprise
+    /// account, then it should use [`AuthMode::ApiKey`].
+    #[tokio::test]
+    async fn enterprise_account_with_api_key_uses_apikey_auth() {
+        let codex_home = tempdir().unwrap();
+        write_auth_file(
+            AuthFileParams {
+                openai_api_key: Some("sk-test-key".to_string()),
+                chatgpt_plan_type: "enterprise".to_string(),
+            },
+            codex_home.path(),
+        )
+        .expect("failed to write auth file");
+
+        let CodexAuth {
+            api_key,
+            mode,
+            auth_dot_json,
+            auth_file: _,
+            ..
+        } = super::load_auth(codex_home.path(), false, AuthMode::ChatGPT, "codex_cli_rs")
+            .unwrap()
+            .unwrap();
+        assert_eq!(Some("sk-test-key".to_string()), api_key);
+        assert_eq!(AuthMode::ApiKey, mode);
+
+        let guard = auth_dot_json.lock().expect("should unwrap");
+        assert!(guard.is_none(), "auth_dot_json should be None");
+    }
+
    #[tokio::test]
    async fn loads_api_key_from_auth_json() {
        let dir = tempdir().unwrap();
@@ -465,7 +596,9 @@ mod tests {
        )
        .unwrap();

-        let auth = super::load_auth(dir.path()).unwrap().unwrap();
+        let auth = super::load_auth(dir.path(), false, AuthMode::ChatGPT, "codex_cli_rs")
+            .unwrap()
+            .unwrap();
        assert_eq!(auth.mode, AuthMode::ApiKey);
        assert_eq!(auth.api_key, Some("sk-test-key".to_string()));

@@ -547,6 +680,7 @@ mod tests {
 #[derive(Debug)]
 pub struct AuthManager {
    codex_home: PathBuf,
+    originator: String,
    inner: RwLock<CachedAuth>,
 }

@@ -555,19 +689,30 @@ impl AuthManager {
    /// preferred auth method. Errors loading auth are swallowed; `auth()` will
    /// simply return `None` in that case so callers can treat it as an
    /// unauthenticated state.
-    pub fn new(codex_home: PathBuf) -> Self {
-        let auth = CodexAuth::from_codex_home(&codex_home).ok().flatten();
+    pub fn new(codex_home: PathBuf, preferred_auth_mode: AuthMode, originator: String) -> Self {
+        let auth = CodexAuth::from_codex_home(&codex_home, preferred_auth_mode, &originator)
+            .ok()
+            .flatten();
        Self {
            codex_home,
-            inner: RwLock::new(CachedAuth { auth }),
+            originator,
+            inner: RwLock::new(CachedAuth {
+                preferred_auth_mode,
+                auth,
+            }),
        }
    }

    /// Create an AuthManager with a specific CodexAuth, for testing only.
    pub fn from_auth_for_testing(auth: CodexAuth) -> Arc<Self> {
-        let cached = CachedAuth { auth: Some(auth) };
+        let preferred_auth_mode = auth.mode;
+        let cached = CachedAuth {
+            preferred_auth_mode,
+            auth: Some(auth),
+        };
        Arc::new(Self {
            codex_home: PathBuf::new(),
+            originator: "codex_cli_rs".to_string(),
            inner: RwLock::new(cached),
        })
    }
@@ -577,10 +722,21 @@ impl AuthManager {
        self.inner.read().ok().and_then(|c| c.auth.clone())
    }

-    /// Force a reload of the auth information from auth.json. Returns
+    /// Preferred auth method used when (re)loading.
+    pub fn preferred_auth_method(&self) -> AuthMode {
+        self.inner
+            .read()
+            .map(|c| c.preferred_auth_mode)
+            .unwrap_or(AuthMode::ApiKey)
+    }
+
+    /// Force a reload using the existing preferred auth method. Returns
    /// whether the auth value changed.
    pub fn reload(&self) -> bool {
-        let new_auth = CodexAuth::from_codex_home(&self.codex_home).ok().flatten();
+        let preferred = self.preferred_auth_method();
+        let new_auth = CodexAuth::from_codex_home(&self.codex_home, preferred, &self.originator)
+            .ok()
+            .flatten();
        if let Ok(mut guard) = self.inner.write() {
            let changed = !AuthManager::auths_equal(&guard.auth, &new_auth);
            guard.auth = new_auth;
@@ -599,8 +755,12 @@ impl AuthManager {
    }

    /// Convenience constructor returning an `Arc` wrapper.
-    pub fn shared(codex_home: PathBuf) -> Arc<Self> {
-        Arc::new(Self::new(codex_home))
+    pub fn shared(
+        codex_home: PathBuf,
+        preferred_auth_mode: AuthMode,
+        originator: String,
+    ) -> Arc<Self> {
+        Arc::new(Self::new(codex_home, preferred_auth_mode, originator))
    }

    /// Attempt to refresh the current auth token (if any). On success, reload
--- a/codex-rs/core/src/client.rs
+++ b/codex-rs/core/src/client.rs
@@ -41,7 +41,6 @@ use crate::model_provider_info::WireApi;
 use crate::openai_model_info::get_model_info;
 use crate::openai_tools::create_tools_json_for_responses_api;
 use crate::protocol::TokenUsage;
-use crate::token_data::PlanType;
 use crate::util::backoff;
 use codex_protocol::config_types::ReasoningEffort as ReasoningEffortConfig;
 use codex_protocol::config_types::ReasoningSummary as ReasoningSummaryConfig;
@@ -61,7 +60,7 @@ struct Error {
    message: Option<String>,

    // Optional fields available on "usage_limit_reached" and "usage_not_included" errors
-    plan_type: Option<PlanType>,
+    plan_type: Option<String>,
    resets_in_seconds: Option<u64>,
 }

@@ -85,7 +84,7 @@ impl ModelClient {
        summary: ReasoningSummaryConfig,
        conversation_id: ConversationId,
    ) -> Self {
-        let client = create_client();
+        let client = create_client(&config.responses_originator_header);

        Self {
            config,
@@ -240,10 +239,10 @@ impl ModelClient {
            let res = req_builder.send().await;
            if let Ok(resp) = &res {
                trace!(
-                    "Response status: {}, cf-ray: {}",
+                    "Response status: {}, request-id: {}",
                    resp.status(),
                    resp.headers()
-                        .get("cf-ray")
+                        .get("x-request-id")
                        .map(|v| v.to_str().unwrap_or_default())
                        .unwrap_or_default()
                );
@@ -305,7 +304,7 @@ impl ModelClient {
                                // token.
                                let plan_type = error
                                    .plan_type
-                                    .or_else(|| auth.as_ref().and_then(|a| a.get_plan_type()));
+                                    .or_else(|| auth.and_then(|a| a.get_plan_type()));
                                let resets_in_seconds = error.resets_in_seconds;
                                return Err(CodexErr::UsageLimitReached(UsageLimitReachedError {
                                    plan_type,
@@ -321,6 +320,9 @@ impl ModelClient {
                        if status == StatusCode::INTERNAL_SERVER_ERROR {
                            return Err(CodexErr::InternalServerError);
                        }
+                        if status == StatusCode::UNAUTHORIZED {
+                            return Err(CodexErr::UnauthorizedError);
+                        }

                        return Err(CodexErr::RetryLimit(status));
                    }
@@ -1038,37 +1040,4 @@ mod tests {
        let delay = try_parse_retry_after(&err);
        assert_eq!(delay, Some(Duration::from_secs_f64(1.898)));
    }
-
-    #[test]
-    fn error_response_deserializes_old_schema_known_plan_type_and_serializes_back() {
-        use crate::token_data::KnownPlan;
-        use crate::token_data::PlanType;
-
-        let json = r#"{"error":{"type":"usage_limit_reached","plan_type":"pro","resets_in_seconds":3600}}"#;
-        let resp: ErrorResponse =
-            serde_json::from_str(json).expect("should deserialize old schema");
-
-        assert!(matches!(
-            resp.error.plan_type,
-            Some(PlanType::Known(KnownPlan::Pro))
-        ));
-
-        let plan_json = serde_json::to_string(&resp.error.plan_type).expect("serialize plan_type");
-        assert_eq!(plan_json, "\"pro\"");
-    }
-
-    #[test]
-    fn error_response_deserializes_old_schema_unknown_plan_type_and_serializes_back() {
-        use crate::token_data::PlanType;
-
-        let json =
-            r#"{"error":{"type":"usage_limit_reached","plan_type":"vip","resets_in_seconds":60}}"#;
-        let resp: ErrorResponse =
-            serde_json::from_str(json).expect("should deserialize old schema");
-
-        assert!(matches!(resp.error.plan_type, Some(PlanType::Unknown(ref s)) if s == "vip"));
-
-        let plan_json = serde_json::to_string(&resp.error.plan_type).expect("serialize plan_type");
-        assert_eq!(plan_json, "\"vip\"");
-    }
 }
--- a/codex-rs/core/src/codex.rs
+++ b/codex-rs/core/src/codex.rs
--- a/codex-rs/core/src/config.rs
+++ b/codex-rs/core/src/config.rs
@@ -15,11 +15,11 @@ use crate::model_provider_info::built_in_model_providers;
 use crate::openai_model_info::get_model_info;
 use crate::protocol::AskForApproval;
 use crate::protocol::SandboxPolicy;
-use anyhow::Context;
 use codex_protocol::config_types::ReasoningEffort;
 use codex_protocol::config_types::ReasoningSummary;
 use codex_protocol::config_types::SandboxMode;
 use codex_protocol::config_types::Verbosity;
+use codex_protocol::mcp_protocol::AuthMode;
 use codex_protocol::mcp_protocol::Tools;
 use codex_protocol::mcp_protocol::UserSavedConfig;
 use dirs::home_dir;
@@ -32,14 +32,15 @@ use toml::Value as TomlValue;
 use toml_edit::DocumentMut;

 const OPENAI_DEFAULT_MODEL: &str = "gpt-5";
-pub const GPT5_HIGH_MODEL: &str = "gpt-5-high";

 /// Maximum number of bytes of the documentation that will be embedded. Larger
 /// files are *silently truncated* to this size so we do not take up too much of
 /// the context window.
 pub(crate) const PROJECT_DOC_MAX_BYTES: usize = 32 * 1024; // 32 KiB

-pub(crate) const CONFIG_TOML_FILE: &str = "config.toml";
+const CONFIG_TOML_FILE: &str = "config.toml";
+
+const DEFAULT_RESPONSES_ORIGINATOR_HEADER: &str = "codex_cli_rs";

 /// Application configuration loaded from disk and merged with overrides.
 #[derive(Debug, Clone, PartialEq)]
@@ -130,6 +131,9 @@ pub struct Config {
    /// output will be hyperlinked using the specified URI scheme.
    pub file_opener: UriBasedFileOpener,

+    /// Collection of settings that are specific to the TUI.
+    pub tui: Tui,
+
    /// Path to the `codex-linux-sandbox` executable. This must be set if
    /// [`crate::exec::SandboxType::LinuxSeccomp`] is used. Note that this
    /// cannot be set in the config file: it must be set in code via
@@ -165,17 +169,16 @@ pub struct Config {

    pub tools_web_search_request: bool,

-    pub use_experimental_streamable_shell_tool: bool,
+    /// The value for the `originator` header included with Responses API requests.
+    pub responses_originator_header: String,

-    /// If set to `true`, used only the experimental unified exec tool.
-    pub use_experimental_unified_exec_tool: bool,
+    /// If set to `true`, the API key will be signed with the `originator` header.
+    pub preferred_auth_method: AuthMode,
+
+    pub use_experimental_streamable_shell_tool: bool,

    /// Include the `view_image` tool that lets the agent attach a local image path to context.
    pub include_view_image_tool: bool,
-
-    /// The active profile name used to derive this `Config` (if any).
-    pub active_profile: Option<String>,
-
    /// When true, disables burst-paste detection for typed input entirely.
    /// All characters are inserted as they are received, and no buffering
    /// or placeholder replacement will occur for fast keypress bursts.
@@ -259,7 +262,17 @@ pub fn load_config_as_toml(codex_home: &Path) -> std::io::Result<TomlValue> {
    }
 }

-fn set_project_trusted_inner(doc: &mut DocumentMut, project_path: &Path) -> anyhow::Result<()> {
+/// Patch `CODEX_HOME/config.toml` project state.
+/// Use with caution.
+pub fn set_project_trusted(codex_home: &Path, project_path: &Path) -> anyhow::Result<()> {
+    let config_path = codex_home.join(CONFIG_TOML_FILE);
+    // Parse existing config if present; otherwise start a new document.
+    let mut doc = match std::fs::read_to_string(config_path.clone()) {
+        Ok(s) => s.parse::<DocumentMut>()?,
+        Err(e) if e.kind() == std::io::ErrorKind::NotFound => DocumentMut::new(),
+        Err(e) => return Err(e.into()),
+    };
+
    // Ensure we render a human-friendly structure:
    //
    // [projects]
@@ -275,26 +288,14 @@ fn set_project_trusted_inner(doc: &mut DocumentMut, project_path: &Path) -> anyh
    // Ensure top-level `projects` exists as a non-inline, explicit table. If it
    // exists but was previously represented as a non-table (e.g., inline),
    // replace it with an explicit table.
+    let mut created_projects_table = false;
    {
        let root = doc.as_table_mut();
-        // If `projects` exists but isn't a standard table (e.g., it's an inline table),
-        // convert it to an explicit table while preserving existing entries.
-        let existing_projects = root.get("projects").cloned();
-        if existing_projects.as_ref().is_none_or(|i| !i.is_table()) {
-            let mut projects_tbl = toml_edit::Table::new();
-            projects_tbl.set_implicit(true);
-
-            // If there was an existing inline table, migrate its entries to explicit tables.
-            if let Some(inline_tbl) = existing_projects.as_ref().and_then(|i| i.as_inline_table()) {
-                for (k, v) in inline_tbl.iter() {
-                    if let Some(inner_tbl) = v.as_inline_table() {
-                        let new_tbl = inner_tbl.clone().into_table();
-                        projects_tbl.insert(k, toml_edit::Item::Table(new_tbl));
-                    }
-                }
-            }
-
-            root.insert("projects", toml_edit::Item::Table(projects_tbl));
+        let needs_table = !root.contains_key("projects")
+            || root.get("projects").and_then(|i| i.as_table()).is_none();
+        if needs_table {
+            root.insert("projects", toml_edit::table());
+            created_projects_table = true;
        }
    }
    let Some(projects_tbl) = doc["projects"].as_table_mut() else {
@@ -303,6 +304,12 @@ fn set_project_trusted_inner(doc: &mut DocumentMut, project_path: &Path) -> anyh
        ));
    };

+    // If we created the `projects` table ourselves, keep it implicit so we
+    // don't render a standalone `[projects]` header.
+    if created_projects_table {
+        projects_tbl.set_implicit(true);
+    }
+
    // Ensure the per-project entry is its own explicit table. If it exists but
    // is not a table (e.g., an inline table), replace it with an explicit table.
    let needs_proj_table = !projects_tbl.contains_key(project_key.as_str())
@@ -321,21 +328,6 @@ fn set_project_trusted_inner(doc: &mut DocumentMut, project_path: &Path) -> anyh
    };
    proj_tbl.set_implicit(false);
    proj_tbl["trust_level"] = toml_edit::value("trusted");
-    Ok(())
-}
-
-/// Patch `CODEX_HOME/config.toml` project state.
-/// Use with caution.
-pub fn set_project_trusted(codex_home: &Path, project_path: &Path) -> anyhow::Result<()> {
-    let config_path = codex_home.join(CONFIG_TOML_FILE);
-    // Parse existing config if present; otherwise start a new document.
-    let mut doc = match std::fs::read_to_string(config_path.clone()) {
-        Ok(s) => s.parse::<DocumentMut>()?,
-        Err(e) if e.kind() == std::io::ErrorKind::NotFound => DocumentMut::new(),
-        Err(e) => return Err(e.into()),
-    };
-
-    set_project_trusted_inner(&mut doc, project_path)?;

    // ensure codex_home exists
    std::fs::create_dir_all(codex_home)?;
@@ -350,107 +342,6 @@ pub fn set_project_trusted(codex_home: &Path, project_path: &Path) -> anyhow::Re
    Ok(())
 }

-fn ensure_profile_table<'a>(
-    doc: &'a mut DocumentMut,
-    profile_name: &str,
-) -> anyhow::Result<&'a mut toml_edit::Table> {
-    let mut created_profiles_table = false;
-    {
-        let root = doc.as_table_mut();
-        let needs_table = !root.contains_key("profiles")
-            || root
-                .get("profiles")
-                .and_then(|item| item.as_table())
-                .is_none();
-        if needs_table {
-            root.insert("profiles", toml_edit::table());
-            created_profiles_table = true;
-        }
-    }
-
-    let Some(profiles_table) = doc["profiles"].as_table_mut() else {
-        return Err(anyhow::anyhow!(
-            "profiles table missing after initialization"
-        ));
-    };
-
-    if created_profiles_table {
-        profiles_table.set_implicit(true);
-    }
-
-    let needs_profile_table = !profiles_table.contains_key(profile_name)
-        || profiles_table
-            .get(profile_name)
-            .and_then(|item| item.as_table())
-            .is_none();
-    if needs_profile_table {
-        profiles_table.insert(profile_name, toml_edit::table());
-    }
-
-    let Some(profile_table) = profiles_table
-        .get_mut(profile_name)
-        .and_then(|item| item.as_table_mut())
-    else {
-        return Err(anyhow::anyhow!(format!(
-            "profile table missing for {profile_name}"
-        )));
-    };
-
-    profile_table.set_implicit(false);
-    Ok(profile_table)
-}
-
-// TODO(jif) refactor config persistence.
-pub async fn persist_model_selection(
-    codex_home: &Path,
-    active_profile: Option<&str>,
-    model: &str,
-    effort: Option<ReasoningEffort>,
-) -> anyhow::Result<()> {
-    let config_path = codex_home.join(CONFIG_TOML_FILE);
-    let serialized = match tokio::fs::read_to_string(&config_path).await {
-        Ok(contents) => contents,
-        Err(err) if err.kind() == std::io::ErrorKind::NotFound => String::new(),
-        Err(err) => return Err(err.into()),
-    };
-
-    let mut doc = if serialized.is_empty() {
-        DocumentMut::new()
-    } else {
-        serialized.parse::<DocumentMut>()?
-    };
-
-    if let Some(profile_name) = active_profile {
-        let profile_table = ensure_profile_table(&mut doc, profile_name)?;
-        profile_table["model"] = toml_edit::value(model);
-        if let Some(effort) = effort {
-            profile_table["model_reasoning_effort"] = toml_edit::value(effort.to_string());
-        }
-    } else {
-        let table = doc.as_table_mut();
-        table["model"] = toml_edit::value(model);
-        if let Some(effort) = effort {
-            table["model_reasoning_effort"] = toml_edit::value(effort.to_string());
-        }
-    }
-
-    // TODO(jif) refactor the home creation
-    tokio::fs::create_dir_all(codex_home)
-        .await
-        .with_context(|| {
-            format!(
-                "failed to create Codex home directory at {}",
-                codex_home.display()
-            )
-        })?;
-
-    tokio::fs::write(&config_path, doc.to_string())
-        .await
-        .with_context(|| format!("failed to persist config.toml at {}", config_path.display()))?;
-
-    Ok(())
-}
-
 /// Apply a single dotted-path override onto a TOML value.
 fn apply_toml_override(root: &mut TomlValue, path: &str, value: TomlValue) {
    use toml::value::Table;
@@ -495,7 +386,7 @@ fn apply_toml_override(root: &mut TomlValue, path: &str, value: TomlValue) {
 }

 /// Base config deserialized from ~/.codex/config.toml.
-#[derive(Deserialize, Debug, Clone, Default, PartialEq)]
+#[derive(Deserialize, Debug, Clone, Default)]
 pub struct ConfigToml {
    /// Optional override of model selection.
    pub model: Option<String>,
@@ -586,10 +477,15 @@ pub struct ConfigToml {
    pub experimental_instructions_file: Option<PathBuf>,

    pub experimental_use_exec_command_tool: Option<bool>,
-    pub experimental_use_unified_exec_tool: Option<bool>,
+
+    /// The value for the `originator` header included with Responses API requests.
+    pub responses_originator_header_internal_override: Option<String>,

    pub projects: Option<HashMap<String, ProjectConfig>>,

+    /// If set to `true`, the API key will be signed with the `originator` header.
+    pub preferred_auth_method: Option<AuthMode>,
+
    /// Nested tools section for feature toggles
    pub tools: Option<ToolsToml>,

@@ -627,7 +523,7 @@ pub struct ProjectConfig {
    pub trust_level: Option<String>,
 }

-#[derive(Deserialize, Debug, Clone, Default, PartialEq)]
+#[derive(Deserialize, Debug, Clone, Default)]
 pub struct ToolsToml {
    #[serde(default, alias = "web_search_request")]
    pub web_search: Option<bool>,
@@ -765,11 +661,7 @@ impl Config {
            tools_web_search_request: override_tools_web_search_request,
        } = overrides;

-        let active_profile_name = config_profile_key
-            .as_ref()
-            .or(cfg.profile.as_ref())
-            .cloned();
-        let config_profile = match active_profile_name.as_ref() {
+        let config_profile = match config_profile_key.as_ref().or(cfg.profile.as_ref()) {
            Some(key) => cfg
                .profiles
                .get(key)
@@ -881,6 +773,10 @@ impl Config {
            Self::get_base_instructions(experimental_instructions_path, &resolved_cwd)?;
        let base_instructions = base_instructions.or(file_base_instructions);

+        let responses_originator_header: String = cfg
+            .responses_originator_header_internal_override
+            .unwrap_or(DEFAULT_RESPONSES_ORIGINATOR_HEADER.to_owned());
+
        let config = Self {
            model,
            model_family,
@@ -904,6 +800,7 @@ impl Config {
            codex_home,
            history,
            file_opener: cfg.file_opener.unwrap_or(UriBasedFileOpener::VsCode),
+            tui: cfg.tui.unwrap_or_default(),
            codex_linux_sandbox_exe,

            hide_agent_reasoning: cfg.hide_agent_reasoning.unwrap_or(false),
@@ -929,14 +826,12 @@ impl Config {
            include_plan_tool: include_plan_tool.unwrap_or(false),
            include_apply_patch_tool: include_apply_patch_tool.unwrap_or(false),
            tools_web_search_request,
+            responses_originator_header,
+            preferred_auth_method: cfg.preferred_auth_method.unwrap_or(AuthMode::ChatGPT),
            use_experimental_streamable_shell_tool: cfg
                .experimental_use_exec_command_tool
                .unwrap_or(false),
-            use_experimental_unified_exec_tool: cfg
-                .experimental_use_unified_exec_tool
-                .unwrap_or(false),
            include_view_image_tool,
-            active_profile: active_profile_name,
            disable_paste_burst: cfg.disable_paste_burst.unwrap_or(false),
        };
        Ok(config)
@@ -1047,7 +942,6 @@ mod tests {

    use super::*;
    use pretty_assertions::assert_eq;
-
    use tempfile::TempDir;

    #[test]
@@ -1138,145 +1032,6 @@ exclude_slash_tmp = true
        );
    }

-    #[tokio::test]
-    async fn persist_model_selection_updates_defaults() -> anyhow::Result<()> {
-        let codex_home = TempDir::new()?;
-
-        persist_model_selection(
-            codex_home.path(),
-            None,
-            "gpt-5-high-new",
-            Some(ReasoningEffort::High),
-        )
-        .await?;
-
-        let serialized =
-            tokio::fs::read_to_string(codex_home.path().join(CONFIG_TOML_FILE)).await?;
-        let parsed: ConfigToml = toml::from_str(&serialized)?;
-
-        assert_eq!(parsed.model.as_deref(), Some("gpt-5-high-new"));
-        assert_eq!(parsed.model_reasoning_effort, Some(ReasoningEffort::High));
-
-        Ok(())
-    }
-
-    #[tokio::test]
-    async fn persist_model_selection_overwrites_existing_model() -> anyhow::Result<()> {
-        let codex_home = TempDir::new()?;
-        let config_path = codex_home.path().join(CONFIG_TOML_FILE);
-
-        tokio::fs::write(
-            &config_path,
-            r#"
-model = "gpt-5"
-model_reasoning_effort = "medium"
-
-[profiles.dev]
-model = "gpt-4.1"
-"#,
-        )
-        .await?;
-
-        persist_model_selection(
-            codex_home.path(),
-            None,
-            "o4-mini",
-            Some(ReasoningEffort::High),
-        )
-        .await?;
-
-        let serialized = tokio::fs::read_to_string(config_path).await?;
-        let parsed: ConfigToml = toml::from_str(&serialized)?;
-
-        assert_eq!(parsed.model.as_deref(), Some("o4-mini"));
-        assert_eq!(parsed.model_reasoning_effort, Some(ReasoningEffort::High));
-        assert_eq!(
-            parsed
-                .profiles
-                .get("dev")
-                .and_then(|profile| profile.model.as_deref()),
-            Some("gpt-4.1"),
-        );
-
-        Ok(())
-    }
-
-    #[tokio::test]
-    async fn persist_model_selection_updates_profile() -> anyhow::Result<()> {
-        let codex_home = TempDir::new()?;
-
-        persist_model_selection(
-            codex_home.path(),
-            Some("dev"),
-            "gpt-5-high-new",
-            Some(ReasoningEffort::Low),
-        )
-        .await?;
-
-        let serialized =
-            tokio::fs::read_to_string(codex_home.path().join(CONFIG_TOML_FILE)).await?;
-        let parsed: ConfigToml = toml::from_str(&serialized)?;
-        let profile = parsed
-            .profiles
-            .get("dev")
-            .expect("profile should be created");
-
-        assert_eq!(profile.model.as_deref(), Some("gpt-5-high-new"));
-        assert_eq!(profile.model_reasoning_effort, Some(ReasoningEffort::Low));
-
-        Ok(())
-    }
-
-    #[tokio::test]
-    async fn persist_model_selection_updates_existing_profile() -> anyhow::Result<()> {
-        let codex_home = TempDir::new()?;
-        let config_path = codex_home.path().join(CONFIG_TOML_FILE);
-
-        tokio::fs::write(
-            &config_path,
-            r#"
-[profiles.dev]
-model = "gpt-4"
-model_reasoning_effort = "medium"
-
-[profiles.prod]
-model = "gpt-5"
-"#,
-        )
-        .await?;
-
-        persist_model_selection(
-            codex_home.path(),
-            Some("dev"),
-            "o4-high",
-            Some(ReasoningEffort::Medium),
-        )
-        .await?;
-
-        let serialized = tokio::fs::read_to_string(config_path).await?;
-        let parsed: ConfigToml = toml::from_str(&serialized)?;
-
-        let dev_profile = parsed
-            .profiles
-            .get("dev")
-            .expect("dev profile should survive updates");
-        assert_eq!(dev_profile.model.as_deref(), Some("o4-high"));
-        assert_eq!(
-            dev_profile.model_reasoning_effort,
-            Some(ReasoningEffort::Medium)
-        );
-
-        assert_eq!(
-            parsed
-                .profiles
-                .get("prod")
-                .and_then(|profile| profile.model.as_deref()),
-            Some("gpt-5"),
-        );
-
-        Ok(())
-    }
-
    struct PrecedenceTestFixture {
        cwd: TempDir,
        codex_home: TempDir,
@@ -1435,6 +1190,7 @@ model_verbosity = "high"
                codex_home: fixture.codex_home(),
                history: History::default(),
                file_opener: UriBasedFileOpener::VsCode,
+                tui: Tui::default(),
                codex_linux_sandbox_exe: None,
                hide_agent_reasoning: false,
                show_raw_agent_reasoning: false,
@@ -1447,10 +1203,10 @@ model_verbosity = "high"
                include_plan_tool: false,
                include_apply_patch_tool: false,
                tools_web_search_request: false,
+                responses_originator_header: "codex_cli_rs".to_string(),
+                preferred_auth_method: AuthMode::ChatGPT,
                use_experimental_streamable_shell_tool: false,
-                use_experimental_unified_exec_tool: false,
                include_view_image_tool: true,
-                active_profile: Some("o3".to_string()),
                disable_paste_burst: false,
            },
            o3_profile_config
@@ -1491,6 +1247,7 @@ model_verbosity = "high"
            codex_home: fixture.codex_home(),
            history: History::default(),
            file_opener: UriBasedFileOpener::VsCode,
+            tui: Tui::default(),
            codex_linux_sandbox_exe: None,
            hide_agent_reasoning: false,
            show_raw_agent_reasoning: false,
@@ -1503,10 +1260,10 @@ model_verbosity = "high"
            include_plan_tool: false,
            include_apply_patch_tool: false,
            tools_web_search_request: false,
+            responses_originator_header: "codex_cli_rs".to_string(),
+            preferred_auth_method: AuthMode::ChatGPT,
            use_experimental_streamable_shell_tool: false,
-            use_experimental_unified_exec_tool: false,
            include_view_image_tool: true,
-            active_profile: Some("gpt3".to_string()),
            disable_paste_burst: false,
        };

@@ -1562,6 +1319,7 @@ model_verbosity = "high"
            codex_home: fixture.codex_home(),
            history: History::default(),
            file_opener: UriBasedFileOpener::VsCode,
+            tui: Tui::default(),
            codex_linux_sandbox_exe: None,
            hide_agent_reasoning: false,
            show_raw_agent_reasoning: false,
@@ -1574,10 +1332,10 @@ model_verbosity = "high"
            include_plan_tool: false,
            include_apply_patch_tool: false,
            tools_web_search_request: false,
+            responses_originator_header: "codex_cli_rs".to_string(),
+            preferred_auth_method: AuthMode::ChatGPT,
            use_experimental_streamable_shell_tool: false,
-            use_experimental_unified_exec_tool: false,
            include_view_image_tool: true,
-            active_profile: Some("zdr".to_string()),
            disable_paste_burst: false,
        };

@@ -1619,6 +1377,7 @@ model_verbosity = "high"
            codex_home: fixture.codex_home(),
            history: History::default(),
            file_opener: UriBasedFileOpener::VsCode,
+            tui: Tui::default(),
            codex_linux_sandbox_exe: None,
            hide_agent_reasoning: false,
            show_raw_agent_reasoning: false,
@@ -1631,10 +1390,10 @@ model_verbosity = "high"
            include_plan_tool: false,
            include_apply_patch_tool: false,
            tools_web_search_request: false,
+            responses_originator_header: "codex_cli_rs".to_string(),
+            preferred_auth_method: AuthMode::ChatGPT,
            use_experimental_streamable_shell_tool: false,
-            use_experimental_unified_exec_tool: false,
            include_view_image_tool: true,
-            active_profile: Some("gpt5".to_string()),
            disable_paste_burst: false,
        };

@@ -1645,14 +1404,17 @@ model_verbosity = "high"

    #[test]
    fn test_set_project_trusted_writes_explicit_tables() -> anyhow::Result<()> {
-        let project_dir = Path::new("/some/path");
-        let mut doc = DocumentMut::new();
+        let codex_home = TempDir::new().unwrap();
+        let project_dir = TempDir::new().unwrap();

-        set_project_trusted_inner(&mut doc, project_dir)?;
+        // Call the function under test
+        set_project_trusted(codex_home.path(), project_dir.path())?;

-        let contents = doc.to_string();
+        // Read back the generated config.toml and assert exact contents
+        let config_path = codex_home.path().join(CONFIG_TOML_FILE);
+        let contents = std::fs::read_to_string(&config_path)?;

-        let raw_path = project_dir.to_string_lossy();
+        let raw_path = project_dir.path().to_string_lossy();
        let path_str = if raw_path.contains('\\') {
            format!("'{raw_path}'")
        } else {
@@ -1670,10 +1432,12 @@ trust_level = "trusted"

    #[test]
    fn test_set_project_trusted_converts_inline_to_explicit() -> anyhow::Result<()> {
-        let project_dir = Path::new("/some/path");
+        let codex_home = TempDir::new().unwrap();
+        let project_dir = TempDir::new().unwrap();

        // Seed config.toml with an inline project entry under [projects]
-        let raw_path = project_dir.to_string_lossy();
+        let config_path = codex_home.path().join(CONFIG_TOML_FILE);
+        let raw_path = project_dir.path().to_string_lossy();
        let path_str = if raw_path.contains('\\') {
            format!("'{raw_path}'")
        } else {
@@ -1685,12 +1449,13 @@ trust_level = "trusted"
 {path_str} = {{ trust_level = "untrusted" }}
 "#
        );
-        let mut doc = initial.parse::<DocumentMut>()?;
+        std::fs::create_dir_all(codex_home.path())?;
+        std::fs::write(&config_path, initial)?;

        // Run the function; it should convert to explicit tables and set trusted
-        set_project_trusted_inner(&mut doc, project_dir)?;
+        set_project_trusted(codex_home.path(), project_dir.path())?;

-        let contents = doc.to_string();
+        let contents = std::fs::read_to_string(&config_path)?;

        // Assert exact output after conversion to explicit table
        let expected = format!(
@@ -1705,37 +1470,5 @@ trust_level = "trusted"
        Ok(())
    }

-    #[test]
-    fn test_set_project_trusted_migrates_top_level_inline_projects_preserving_entries()
-    -> anyhow::Result<()> {
-        let initial = r#"toplevel = "baz"
-projects = { "/Users/mbolin/code/codex4" = { trust_level = "trusted", foo = "bar" } , "/Users/mbolin/code/codex3" = { trust_level = "trusted" } }
-model = "foo""#;
-        let mut doc = initial.parse::<DocumentMut>()?;
-
-        // Approve a new directory
-        let new_project = Path::new("/Users/mbolin/code/codex2");
-        set_project_trusted_inner(&mut doc, new_project)?;
-
-        let contents = doc.to_string();
-
-        // Since we created the [projects] table as part of migration, it is kept implicit.
-        // Expect explicit per-project tables, preserving prior entries and appending the new one.
-        let expected = r#"toplevel = "baz"
-model = "foo"
-
-[projects."/Users/mbolin/code/codex4"]
-trust_level = "trusted"
-foo = "bar"
-
-[projects."/Users/mbolin/code/codex3"]
-trust_level = "trusted"
-
-[projects."/Users/mbolin/code/codex2"]
-trust_level = "trusted"
-"#;
-        assert_eq!(contents, expected);
-
-        Ok(())
-    }
+    // No test enforcing the presence of a standalone [projects] header.
 }
--- a/codex-rs/core/src/config_edit.rs
+++ b/codex-rs/core/src/config_edit.rs
@@ -1,582 +0,0 @@
-use crate::config::CONFIG_TOML_FILE;
-use anyhow::Result;
-use std::path::Path;
-use tempfile::NamedTempFile;
-use toml_edit::DocumentMut;
-
-pub const CONFIG_KEY_MODEL: &str = "model";
-pub const CONFIG_KEY_EFFORT: &str = "model_reasoning_effort";
-
-/// Persist overrides into `config.toml` using explicit key segments per
-/// override. This avoids ambiguity with keys that contain dots or spaces.
-pub async fn persist_overrides(
-    codex_home: &Path,
-    profile: Option<&str>,
-    overrides: &[(&[&str], &str)],
-) -> Result<()> {
-    let config_path = codex_home.join(CONFIG_TOML_FILE);
-
-    let mut doc = match tokio::fs::read_to_string(&config_path).await {
-        Ok(s) => s.parse::<DocumentMut>()?,
-        Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
-            tokio::fs::create_dir_all(codex_home).await?;
-            DocumentMut::new()
-        }
-        Err(e) => return Err(e.into()),
-    };
-
-    let effective_profile = if let Some(p) = profile {
-        Some(p.to_owned())
-    } else {
-        doc.get("profile")
-            .and_then(|i| i.as_str())
-            .map(|s| s.to_string())
-    };
-
-    for (segments, val) in overrides.iter().copied() {
-        let value = toml_edit::value(val);
-        if let Some(ref name) = effective_profile {
-            if segments.first().copied() == Some("profiles") {
-                apply_toml_edit_override_segments(&mut doc, segments, value);
-            } else {
-                let mut seg_buf: Vec<&str> = Vec::with_capacity(2 + segments.len());
-                seg_buf.push("profiles");
-                seg_buf.push(name.as_str());
-                seg_buf.extend_from_slice(segments);
-                apply_toml_edit_override_segments(&mut doc, &seg_buf, value);
-            }
-        } else {
-            apply_toml_edit_override_segments(&mut doc, segments, value);
-        }
-    }
-
-    let tmp_file = NamedTempFile::new_in(codex_home)?;
-    tokio::fs::write(tmp_file.path(), doc.to_string()).await?;
-    tmp_file.persist(config_path)?;
-
-    Ok(())
-}
-
-/// Persist overrides where values may be optional. Any entries with `None`
-/// values are skipped. If all values are `None`, this becomes a no-op and
-/// returns `Ok(())` without touching the file.
-pub async fn persist_non_null_overrides(
-    codex_home: &Path,
-    profile: Option<&str>,
-    overrides: &[(&[&str], Option<&str>)],
-) -> Result<()> {
-    let filtered: Vec<(&[&str], &str)> = overrides
-        .iter()
-        .filter_map(|(k, v)| v.map(|vv| (*k, vv)))
-        .collect();
-
-    if filtered.is_empty() {
-        return Ok(());
-    }
-
-    persist_overrides(codex_home, profile, &filtered).await
-}
-
-/// Apply a single override onto a `toml_edit` document while preserving
-/// existing formatting/comments.
-/// The key is expressed as explicit segments to correctly handle keys that
-/// contain dots or spaces.
-fn apply_toml_edit_override_segments(
-    doc: &mut DocumentMut,
-    segments: &[&str],
-    value: toml_edit::Item,
-) {
-    use toml_edit::Item;
-
-    if segments.is_empty() {
-        return;
-    }
-
-    let mut current = doc.as_table_mut();
-    for seg in &segments[..segments.len() - 1] {
-        if !current.contains_key(seg) {
-            current[*seg] = Item::Table(toml_edit::Table::new());
-            if let Some(t) = current[*seg].as_table_mut() {
-                t.set_implicit(true);
-            }
-        }
-
-        let maybe_item = current.get_mut(seg);
-        let Some(item) = maybe_item else { return };
-
-        if !item.is_table() {
-            *item = Item::Table(toml_edit::Table::new());
-            if let Some(t) = item.as_table_mut() {
-                t.set_implicit(true);
-            }
-        }
-
-        let Some(tbl) = item.as_table_mut() else {
-            return;
-        };
-        current = tbl;
-    }
-
-    let last = segments[segments.len() - 1];
-    current[last] = value;
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use pretty_assertions::assert_eq;
-    use tempfile::tempdir;
-
-    /// Verifies model and effort are written at top-level when no profile is set.
-    #[tokio::test]
-    async fn set_default_model_and_effort_top_level_when_no_profile() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        persist_overrides(
-            codex_home,
-            None,
-            &[
-                (&[CONFIG_KEY_MODEL], "gpt-5"),
-                (&[CONFIG_KEY_EFFORT], "high"),
-            ],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"model = "gpt-5"
-model_reasoning_effort = "high"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies values are written under the active profile when `profile` is set.
-    #[tokio::test]
-    async fn set_defaults_update_profile_when_profile_set() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // Seed config with a profile selection but without profiles table
-        let seed = "profile = \"o3\"\n";
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        persist_overrides(
-            codex_home,
-            None,
-            &[
-                (&[CONFIG_KEY_MODEL], "o3"),
-                (&[CONFIG_KEY_EFFORT], "minimal"),
-            ],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"profile = "o3"
-
-[profiles.o3]
-model = "o3"
-model_reasoning_effort = "minimal"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies profile names with dots/spaces are preserved via explicit segments.
-    #[tokio::test]
-    async fn set_defaults_update_profile_with_dot_and_space() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // Seed config with a profile name that contains a dot and a space
-        let seed = "profile = \"my.team name\"\n";
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        persist_overrides(
-            codex_home,
-            None,
-            &[
-                (&[CONFIG_KEY_MODEL], "o3"),
-                (&[CONFIG_KEY_EFFORT], "minimal"),
-            ],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"profile = "my.team name"
-
-[profiles."my.team name"]
-model = "o3"
-model_reasoning_effort = "minimal"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies explicit profile override writes under that profile even without active profile.
-    #[tokio::test]
-    async fn set_defaults_update_when_profile_override_supplied() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // No profile key in config.toml
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), "")
-            .await
-            .expect("seed write");
-
-        // Persist with an explicit profile override
-        persist_overrides(
-            codex_home,
-            Some("o3"),
-            &[(&[CONFIG_KEY_MODEL], "o3"), (&[CONFIG_KEY_EFFORT], "high")],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"[profiles.o3]
-model = "o3"
-model_reasoning_effort = "high"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies nested tables are created as needed when applying overrides.
-    #[tokio::test]
-    async fn persist_overrides_creates_nested_tables() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        persist_overrides(
-            codex_home,
-            None,
-            &[
-                (&["a", "b", "c"], "v"),
-                (&["x"], "y"),
-                (&["profiles", "p1", CONFIG_KEY_MODEL], "gpt-5"),
-            ],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"x = "y"
-
-[a.b]
-c = "v"
-
-[profiles.p1]
-model = "gpt-5"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies a scalar key becomes a table when nested keys are written.
-    #[tokio::test]
-    async fn persist_overrides_replaces_scalar_with_table() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-        let seed = "foo = \"bar\"\n";
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        persist_overrides(codex_home, None, &[(&["foo", "bar", "baz"], "ok")])
-            .await
-            .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"[foo.bar]
-baz = "ok"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies comments and spacing are preserved when writing under active profile.
-    #[tokio::test]
-    async fn set_defaults_preserve_comments() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // Seed a config with comments and spacing we expect to preserve
-        let seed = r#"# Global comment
-# Another line
-
-profile = "o3"
-
-# Profile settings
-[profiles.o3]
-# keep me
-existing = "keep"
-"#;
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        // Apply defaults; since profile is set, it should write under [profiles.o3]
-        persist_overrides(
-            codex_home,
-            None,
-            &[(&[CONFIG_KEY_MODEL], "o3"), (&[CONFIG_KEY_EFFORT], "high")],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"# Global comment
-# Another line
-
-profile = "o3"
-
-# Profile settings
-[profiles.o3]
-# keep me
-existing = "keep"
-model = "o3"
-model_reasoning_effort = "high"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies comments and spacing are preserved when writing at top level.
-    #[tokio::test]
-    async fn set_defaults_preserve_global_comments() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // Seed a config WITHOUT a profile, containing comments and spacing
-        let seed = r#"# Top-level comments
-# should be preserved
-
-existing = "keep"
-"#;
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        // Since there is no profile, the defaults should be written at top-level
-        persist_overrides(
-            codex_home,
-            None,
-            &[
-                (&[CONFIG_KEY_MODEL], "gpt-5"),
-                (&[CONFIG_KEY_EFFORT], "minimal"),
-            ],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"# Top-level comments
-# should be preserved
-
-existing = "keep"
-model = "gpt-5"
-model_reasoning_effort = "minimal"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies errors on invalid TOML propagate and file is not clobbered.
-    #[tokio::test]
-    async fn persist_overrides_errors_on_parse_failure() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // Write an intentionally invalid TOML file
-        let invalid = "invalid = [unclosed";
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), invalid)
-            .await
-            .expect("seed write");
-
-        // Attempting to persist should return an error and must not clobber the file.
-        let res = persist_overrides(codex_home, None, &[(&["x"], "y")]).await;
-        assert!(res.is_err(), "expected parse error to propagate");
-
-        // File should be unchanged
-        let contents = read_config(codex_home).await;
-        assert_eq!(contents, invalid);
-    }
-
-    /// Verifies changing model only preserves existing effort at top-level.
-    #[tokio::test]
-    async fn changing_only_model_preserves_existing_effort_top_level() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // Seed with an effort value only
-        let seed = "model_reasoning_effort = \"minimal\"\n";
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        // Change only the model
-        persist_overrides(codex_home, None, &[(&[CONFIG_KEY_MODEL], "o3")])
-            .await
-            .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"model_reasoning_effort = "minimal"
-model = "o3"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies changing effort only preserves existing model at top-level.
-    #[tokio::test]
-    async fn changing_only_effort_preserves_existing_model_top_level() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // Seed with a model value only
-        let seed = "model = \"gpt-5\"\n";
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        // Change only the effort
-        persist_overrides(codex_home, None, &[(&[CONFIG_KEY_EFFORT], "high")])
-            .await
-            .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"model = "gpt-5"
-model_reasoning_effort = "high"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies changing model only preserves existing effort in active profile.
-    #[tokio::test]
-    async fn changing_only_model_preserves_effort_in_active_profile() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // Seed with an active profile and an existing effort under that profile
-        let seed = r#"profile = "p1"
-
-[profiles.p1]
-model_reasoning_effort = "low"
-"#;
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        persist_overrides(codex_home, None, &[(&[CONFIG_KEY_MODEL], "o4-mini")])
-            .await
-            .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"profile = "p1"
-
-[profiles.p1]
-model_reasoning_effort = "low"
-model = "o4-mini"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies changing effort only preserves existing model in a profile override.
-    #[tokio::test]
-    async fn changing_only_effort_preserves_model_in_profile_override() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        // No active profile key; we'll target an explicit override
-        let seed = r#"[profiles.team]
-model = "gpt-5"
-"#;
-        tokio::fs::write(codex_home.join(CONFIG_TOML_FILE), seed)
-            .await
-            .expect("seed write");
-
-        persist_overrides(
-            codex_home,
-            Some("team"),
-            &[(&[CONFIG_KEY_EFFORT], "minimal")],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"[profiles.team]
-model = "gpt-5"
-model_reasoning_effort = "minimal"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies `persist_non_null_overrides` skips `None` entries and writes only present values at top-level.
-    #[tokio::test]
-    async fn persist_non_null_skips_none_top_level() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        persist_non_null_overrides(
-            codex_home,
-            None,
-            &[
-                (&[CONFIG_KEY_MODEL], Some("gpt-5")),
-                (&[CONFIG_KEY_EFFORT], None),
-            ],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = "model = \"gpt-5\"\n";
-        assert_eq!(contents, expected);
-    }
-
-    /// Verifies no-op behavior when all provided overrides are `None` (no file created/modified).
-    #[tokio::test]
-    async fn persist_non_null_noop_when_all_none() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        persist_non_null_overrides(
-            codex_home,
-            None,
-            &[(&["a"], None), (&["profiles", "p", "x"], None)],
-        )
-        .await
-        .expect("persist");
-
-        // Should not create config.toml on a pure no-op
-        assert!(!codex_home.join(CONFIG_TOML_FILE).exists());
-    }
-
-    /// Verifies entries are written under the specified profile and `None` entries are skipped.
-    #[tokio::test]
-    async fn persist_non_null_respects_profile_override() {
-        let tmpdir = tempdir().expect("tmp");
-        let codex_home = tmpdir.path();
-
-        persist_non_null_overrides(
-            codex_home,
-            Some("team"),
-            &[
-                (&[CONFIG_KEY_MODEL], Some("o3")),
-                (&[CONFIG_KEY_EFFORT], None),
-            ],
-        )
-        .await
-        .expect("persist");
-
-        let contents = read_config(codex_home).await;
-        let expected = r#"[profiles.team]
-model = "o3"
-"#;
-        assert_eq!(contents, expected);
-    }
-
-    // Test helper moved to bottom per review guidance.
-    async fn read_config(codex_home: &Path) -> String {
-        let p = codex_home.join(CONFIG_TOML_FILE);
-        tokio::fs::read_to_string(p).await.unwrap_or_default()
-    }
-}
--- a/codex-rs/core/src/conversation_history.rs
+++ b/codex-rs/core/src/conversation_history.rs
@@ -1,4 +1,3 @@
-use codex_protocol::models::ContentItem;
 use codex_protocol::models::ResponseItem;

 /// Transcript of conversation history
@@ -60,26 +59,6 @@ impl ConversationHistory {
        kept.reverse();
        self.items = kept;
    }
-
-    pub(crate) fn last_agent_message(&self) -> String {
-        for item in self.items.iter().rev() {
-            if let ResponseItem::Message { role, content, .. } = item
-                && role == "assistant"
-            {
-                return content
-                    .iter()
-                    .find_map(|ci| {
-                        if let ContentItem::OutputText { text } = ci {
-                            Some(text.clone())
-                        } else {
-                            None
-                        }
-                    })
-                    .unwrap_or_default();
-            }
-        }
-        String::new()
-    }
 }

 /// Anything that is not a system message or "reasoning" message is considered
--- a/codex-rs/core/src/conversation_manager.rs
+++ b/codex-rs/core/src/conversation_manager.rs
@@ -13,13 +13,25 @@ use crate::protocol::SessionConfiguredEvent;
 use crate::rollout::RolloutRecorder;
 use codex_protocol::mcp_protocol::ConversationId;
 use codex_protocol::models::ResponseItem;
-use codex_protocol::protocol::InitialHistory;
-use codex_protocol::protocol::RolloutItem;
 use std::collections::HashMap;
 use std::path::PathBuf;
 use std::sync::Arc;
 use tokio::sync::RwLock;

+#[derive(Debug, Clone, PartialEq)]
+pub struct ResumedHistory {
+    pub conversation_id: ConversationId,
+    pub history: Vec<ResponseItem>,
+    pub rollout_path: PathBuf,
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum InitialHistory {
+    New,
+    Resumed(ResumedHistory),
+    Forked(Vec<ResponseItem>),
+}
+
 /// Represents a newly created Codex conversation, including the first event
 /// (which is [`EventMsg::SessionConfigured`]).
 pub struct NewConversation {
@@ -133,15 +145,8 @@ impl ConversationManager {
        self.finalize_spawn(codex, conversation_id).await
    }

-    /// Removes the conversation from the manager's internal map, though the
-    /// conversation is stored as `Arc<CodexConversation>`, it is possible that
-    /// other references to it exist elsewhere. Returns the conversation if the
-    /// conversation was found and removed.
-    pub async fn remove_conversation(
-        &self,
-        conversation_id: &ConversationId,
-    ) -> Option<Arc<CodexConversation>> {
-        self.conversations.write().await.remove(conversation_id)
+    pub async fn remove_conversation(&self, conversation_id: ConversationId) {
+        self.conversations.write().await.remove(&conversation_id);
    }

    /// Fork an existing conversation by dropping the last `drop_last_messages`
@@ -150,13 +155,13 @@ impl ConversationManager {
    /// caller's `config`). The new conversation will have a fresh id.
    pub async fn fork_conversation(
        &self,
+        conversation_history: Vec<ResponseItem>,
        num_messages_to_drop: usize,
        config: Config,
-        path: PathBuf,
    ) -> CodexResult<NewConversation> {
        // Compute the prefix up to the cut point.
-        let history = RolloutRecorder::get_rollout_history(&path).await?;
-        let history = truncate_after_dropping_last_messages(history, num_messages_to_drop);
+        let history =
+            truncate_after_dropping_last_messages(conversation_history, num_messages_to_drop);

        // Spawn a new conversation with the computed initial history.
        let auth_manager = self.auth_manager.clone();
@@ -171,37 +176,31 @@ impl ConversationManager {

 /// Return a prefix of `items` obtained by dropping the last `n` user messages
 /// and all items that follow them.
-fn truncate_after_dropping_last_messages(history: InitialHistory, n: usize) -> InitialHistory {
+fn truncate_after_dropping_last_messages(items: Vec<ResponseItem>, n: usize) -> InitialHistory {
    if n == 0 {
-        return InitialHistory::Forked(history.get_rollout_items());
+        return InitialHistory::Forked(items);
    }

-    // Work directly on rollout items, and cut the vector at the nth-from-last user message input.
-    let items: Vec<RolloutItem> = history.get_rollout_items();
-
-    // Find indices of user message inputs in rollout order.
-    let mut user_positions: Vec<usize> = Vec::new();
-    for (idx, item) in items.iter().enumerate() {
-        if let RolloutItem::ResponseItem(ResponseItem::Message { role, .. }) = item
+    // Walk backwards counting only `user` Message items, find cut index.
+    let mut count = 0usize;
+    let mut cut_index = 0usize;
+    for (idx, item) in items.iter().enumerate().rev() {
+        if let ResponseItem::Message { role, .. } = item
            && role == "user"
        {
-            user_positions.push(idx);
+            count += 1;
+            if count == n {
+                // Cut everything from this user message to the end.
+                cut_index = idx;
+                break;
+            }
        }
    }
-
-    // If fewer than n user messages exist, treat as empty.
-    if user_positions.len() < n {
-        return InitialHistory::New;
-    }
-
-    // Cut strictly before the nth-from-last user message (do not keep the nth itself).
-    let cut_idx = user_positions[user_positions.len() - n];
-    let rolled: Vec<RolloutItem> = items.into_iter().take(cut_idx).collect();
-
-    if rolled.is_empty() {
+    if cut_index == 0 {
+        // No prefix remains after dropping; start a new conversation.
        InitialHistory::New
    } else {
-        InitialHistory::Forked(rolled)
+        InitialHistory::Forked(items.into_iter().take(cut_index).collect())
    }
 }

@@ -256,30 +255,13 @@ mod tests {
            assistant_msg("a4"),
        ];

-        // Wrap as InitialHistory::Forked with response items only.
-        let initial: Vec<RolloutItem> = items
-            .iter()
-            .cloned()
-            .map(RolloutItem::ResponseItem)
-            .collect();
-        let truncated = truncate_after_dropping_last_messages(InitialHistory::Forked(initial), 1);
-        let got_items = truncated.get_rollout_items();
-        let expected_items = vec![
-            RolloutItem::ResponseItem(items[0].clone()),
-            RolloutItem::ResponseItem(items[1].clone()),
-            RolloutItem::ResponseItem(items[2].clone()),
-        ];
+        let truncated = truncate_after_dropping_last_messages(items.clone(), 1);
        assert_eq!(
-            serde_json::to_value(&got_items).unwrap(),
-            serde_json::to_value(&expected_items).unwrap()
+            truncated,
+            InitialHistory::Forked(vec![items[0].clone(), items[1].clone(), items[2].clone(),])
        );

-        let initial2: Vec<RolloutItem> = items
-            .iter()
-            .cloned()
-            .map(RolloutItem::ResponseItem)
-            .collect();
-        let truncated2 = truncate_after_dropping_last_messages(InitialHistory::Forked(initial2), 2);
-        assert!(matches!(truncated2, InitialHistory::New));
+        let truncated2 = truncate_after_dropping_last_messages(items, 2);
+        assert_eq!(truncated2, InitialHistory::New);
    }
 }
--- a/codex-rs/core/src/default_client.rs
+++ b/codex-rs/core/src/default_client.rs
@@ -1,123 +1,38 @@
-use reqwest::header::HeaderValue;
-use std::sync::LazyLock;
-use std::sync::Mutex;
+pub const DEFAULT_ORIGINATOR: &str = "codex_cli_rs";

-/// Set this to add a suffix to the User-Agent string.
-///
-/// It is not ideal that we're using a global singleton for this.
-/// This is primarily designed to differentiate MCP clients from each other.
-/// Because there can only be one MCP server per process, it should be safe for this to be a global static.
-/// However, future users of this should use this with caution as a result.
-/// In addition, we want to be confident that this value is used for ALL clients and doing that requires a
-/// lot of wiring and it's easy to miss code paths by doing so.
-/// See https://github.com/openai/codex/pull/3388/files for an example of what that would look like.
-/// Finally, we want to make sure this is set for ALL mcp clients without needing to know a special env var
-/// or having to set data that they already specified in the mcp initialize request somewhere else.
-///
-/// A space is automatically added between the suffix and the rest of the User-Agent string.
-/// The full user agent string is returned from the mcp initialize response.
-/// Parenthesis will be added by Codex. This should only specify what goes inside of the parenthesis.
-pub static USER_AGENT_SUFFIX: LazyLock<Mutex<Option<String>>> = LazyLock::new(|| Mutex::new(None));
-
-pub const CODEX_INTERNAL_ORIGINATOR_OVERRIDE_ENV_VAR: &str = "CODEX_INTERNAL_ORIGINATOR_OVERRIDE";
-
-#[derive(Debug, Clone)]
-pub struct Originator {
-    pub value: String,
-    pub header_value: HeaderValue,
-}
-
-pub static ORIGINATOR: LazyLock<Originator> = LazyLock::new(|| {
-    let default = "codex_cli_rs";
-    let value = std::env::var(CODEX_INTERNAL_ORIGINATOR_OVERRIDE_ENV_VAR)
-        .unwrap_or_else(|_| default.to_string());
-
-    match HeaderValue::from_str(&value) {
-        Ok(header_value) => Originator {
-            value,
-            header_value,
-        },
-        Err(e) => {
-            tracing::error!("Unable to turn originator override {value} into header value: {e}");
-            Originator {
-                value: default.to_string(),
-                header_value: HeaderValue::from_static(default),
-            }
-        }
-    }
-});
-
-pub fn get_codex_user_agent() -> String {
+pub fn get_codex_user_agent(originator: Option<&str>) -> String {
    let build_version = env!("CARGO_PKG_VERSION");
    let os_info = os_info::get();
-    let prefix = format!(
+    format!(
        "{}/{build_version} ({} {}; {}) {}",
-        ORIGINATOR.value.as_str(),
+        originator.unwrap_or(DEFAULT_ORIGINATOR),
        os_info.os_type(),
        os_info.version(),
        os_info.architecture().unwrap_or("unknown"),
        crate::terminal::user_agent()
-    );
-    let suffix = USER_AGENT_SUFFIX
-        .lock()
-        .ok()
-        .and_then(|guard| guard.clone());
-    let suffix = suffix
-        .as_deref()
-        .map(str::trim)
-        .filter(|value| !value.is_empty())
-        .map_or_else(String::new, |value| format!(" ({value})"));
-
-    let candidate = format!("{prefix}{suffix}");
-    sanitize_user_agent(candidate, &prefix)
-}
-
-/// Sanitize the user agent string.
-///
-/// Invalid characters are replaced with an underscore.
-///
-/// If the user agent fails to parse, it falls back to fallback and then to ORIGINATOR.
-fn sanitize_user_agent(candidate: String, fallback: &str) -> String {
-    if HeaderValue::from_str(candidate.as_str()).is_ok() {
-        return candidate;
-    }
-
-    let sanitized: String = candidate
-        .chars()
-        .map(|ch| if matches!(ch, ' '..='~') { ch } else { '_' })
-        .collect();
-    if !sanitized.is_empty() && HeaderValue::from_str(sanitized.as_str()).is_ok() {
-        tracing::warn!(
-            "Sanitized Codex user agent because provided suffix contained invalid header characters"
-        );
-        sanitized
-    } else if HeaderValue::from_str(fallback).is_ok() {
-        tracing::warn!(
-            "Falling back to base Codex user agent because provided suffix could not be sanitized"
-        );
-        fallback.to_string()
-    } else {
-        tracing::warn!(
-            "Falling back to default Codex originator because base user agent string is invalid"
-        );
-        ORIGINATOR.value.clone()
-    }
+    )
 }

 /// Create a reqwest client with default `originator` and `User-Agent` headers set.
-pub fn create_client() -> reqwest::Client {
+pub fn create_client(originator: &str) -> reqwest::Client {
    use reqwest::header::HeaderMap;
+    use reqwest::header::HeaderValue;

    let mut headers = HeaderMap::new();
-    headers.insert("originator", ORIGINATOR.header_value.clone());
-    let ua = get_codex_user_agent();
+    let originator_value = HeaderValue::from_str(originator)
+        .unwrap_or_else(|_| HeaderValue::from_static(DEFAULT_ORIGINATOR));
+    headers.insert("originator", originator_value);
+    let ua = get_codex_user_agent(Some(originator));

-    reqwest::Client::builder()
+    match reqwest::Client::builder()
        // Set UA via dedicated helper to avoid header validation pitfalls
        .user_agent(ua)
        .default_headers(headers)
        .build()
-        .unwrap_or_else(|_| reqwest::Client::new())
+    {
+        Ok(client) => client,
+        Err(_) => reqwest::Client::new(),
+    }
 }

 #[cfg(test)]
@@ -126,7 +41,7 @@ mod tests {

    #[test]
    fn test_get_codex_user_agent() {
-        let user_agent = get_codex_user_agent();
+        let user_agent = get_codex_user_agent(None);
        assert!(user_agent.starts_with("codex_cli_rs/"));
    }

@@ -138,7 +53,8 @@ mod tests {
        use wiremock::matchers::method;
        use wiremock::matchers::path;

-        let client = create_client();
+        let originator = "test_originator";
+        let client = create_client(originator);

        // Spin up a local mock server and capture a request.
        let server = MockServer::start().await;
@@ -166,43 +82,21 @@ mod tests {
        let originator_header = headers
            .get("originator")
            .expect("originator header missing");
-        assert_eq!(originator_header.to_str().unwrap(), "codex_cli_rs");
+        assert_eq!(originator_header.to_str().unwrap(), originator);

        // User-Agent matches the computed Codex UA for that originator
-        let expected_ua = get_codex_user_agent();
+        let expected_ua = get_codex_user_agent(Some(originator));
        let ua_header = headers
            .get("user-agent")
            .expect("user-agent header missing");
        assert_eq!(ua_header.to_str().unwrap(), expected_ua);
    }

-    #[test]
-    fn test_invalid_suffix_is_sanitized() {
-        let prefix = "codex_cli_rs/0.0.0";
-        let suffix = "bad\rsuffix";
-
-        assert_eq!(
-            sanitize_user_agent(format!("{prefix} ({suffix})"), prefix),
-            "codex_cli_rs/0.0.0 (bad_suffix)"
-        );
-    }
-
-    #[test]
-    fn test_invalid_suffix_is_sanitized2() {
-        let prefix = "codex_cli_rs/0.0.0";
-        let suffix = "bad\0suffix";
-
-        assert_eq!(
-            sanitize_user_agent(format!("{prefix} ({suffix})"), prefix),
-            "codex_cli_rs/0.0.0 (bad_suffix)"
-        );
-    }
-
    #[test]
    #[cfg(target_os = "macos")]
    fn test_macos() {
        use regex_lite::Regex;
-        let user_agent = get_codex_user_agent();
+        let user_agent = get_codex_user_agent(None);
        let re = Regex::new(
            r"^codex_cli_rs/\d+\.\d+\.\d+ \(Mac OS \d+\.\d+\.\d+; (x86_64|arm64)\) (\S+)$",
        )
--- a/codex-rs/core/src/environment_context.rs
+++ b/codex-rs/core/src/environment_context.rs
@@ -26,7 +26,6 @@ pub(crate) struct EnvironmentContext {
    pub approval_policy: Option<AskForApproval>,
    pub sandbox_mode: Option<SandboxMode>,
    pub network_access: Option<NetworkAccess>,
-    pub writable_roots: Option<Vec<PathBuf>>,
    pub shell: Option<Shell>,
 }

@@ -58,16 +57,6 @@ impl EnvironmentContext {
                }
                None => None,
            },
-            writable_roots: match sandbox_policy {
-                Some(SandboxPolicy::WorkspaceWrite { writable_roots, .. }) => {
-                    if writable_roots.is_empty() {
-                        None
-                    } else {
-                        Some(writable_roots)
-                    }
-                }
-                _ => None,
-            },
            shell,
        }
    }
@@ -83,7 +72,6 @@ impl EnvironmentContext {
    ///   <cwd>...</cwd>
    ///   <approval_policy>...</approval_policy>
    ///   <sandbox_mode>...</sandbox_mode>
-    ///   <writable_roots>...</writable_roots>
    ///   <network_access>...</network_access>
    ///   <shell>...</shell>
    /// </environment_context>
@@ -106,16 +94,6 @@ impl EnvironmentContext {
                "  <network_access>{network_access}</network_access>"
            ));
        }
-        if let Some(writable_roots) = self.writable_roots {
-            lines.push("  <writable_roots>".to_string());
-            for writable_root in writable_roots {
-                lines.push(format!(
-                    "    <root>{}</root>",
-                    writable_root.to_string_lossy()
-                ));
-            }
-            lines.push("  </writable_roots>".to_string());
-        }
        if let Some(shell) = self.shell
            && let Some(shell_name) = shell.name()
        {
@@ -137,77 +115,3 @@ impl From<EnvironmentContext> for ResponseItem {
        }
    }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use pretty_assertions::assert_eq;
-
-    fn workspace_write_policy(writable_roots: Vec<&str>, network_access: bool) -> SandboxPolicy {
-        SandboxPolicy::WorkspaceWrite {
-            writable_roots: writable_roots.into_iter().map(PathBuf::from).collect(),
-            network_access,
-            exclude_tmpdir_env_var: false,
-            exclude_slash_tmp: false,
-        }
-    }
-
-    #[test]
-    fn serialize_workspace_write_environment_context() {
-        let context = EnvironmentContext::new(
-            Some(PathBuf::from("/repo")),
-            Some(AskForApproval::OnRequest),
-            Some(workspace_write_policy(vec!["/repo", "/tmp"], false)),
-            None,
-        );
-
-        let expected = r#"<environment_context>
-  <cwd>/repo</cwd>
-  <approval_policy>on-request</approval_policy>
-  <sandbox_mode>workspace-write</sandbox_mode>
-  <network_access>restricted</network_access>
-  <writable_roots>
-    <root>/repo</root>
-    <root>/tmp</root>
-  </writable_roots>
-</environment_context>"#;
-
-        assert_eq!(context.serialize_to_xml(), expected);
-    }
-
-    #[test]
-    fn serialize_read_only_environment_context() {
-        let context = EnvironmentContext::new(
-            None,
-            Some(AskForApproval::Never),
-            Some(SandboxPolicy::ReadOnly),
-            None,
-        );
-
-        let expected = r#"<environment_context>
-  <approval_policy>never</approval_policy>
-  <sandbox_mode>read-only</sandbox_mode>
-  <network_access>restricted</network_access>
-</environment_context>"#;
-
-        assert_eq!(context.serialize_to_xml(), expected);
-    }
-
-    #[test]
-    fn serialize_full_access_environment_context() {
-        let context = EnvironmentContext::new(
-            None,
-            Some(AskForApproval::OnFailure),
-            Some(SandboxPolicy::DangerFullAccess),
-            None,
-        );
-
-        let expected = r#"<environment_context>
-  <approval_policy>on-failure</approval_policy>
-  <sandbox_mode>danger-full-access</sandbox_mode>
-  <network_access>enabled</network_access>
-</environment_context>"#;
-
-        assert_eq!(context.serialize_to_xml(), expected);
-    }
-}
--- a/codex-rs/core/src/error.rs
+++ b/codex-rs/core/src/error.rs
@@ -1,5 +1,3 @@
-use crate::token_data::KnownPlan;
-use crate::token_data::PlanType;
 use codex_protocol::mcp_protocol::ConversationId;
 use reqwest::StatusCode;
 use serde_json;
@@ -85,6 +83,9 @@ pub enum CodexErr {
    #[error("We're currently experiencing high demand, which may cause temporary errors.")]
    InternalServerError,

+    #[error("The API key is invalid or has expired. Please check your API key and try again.")]
+    UnauthorizedError,
+
    /// Retry limit exceeded.
    #[error("exceeded retry limit, last status: {0}")]
    RetryLimit(StatusCode),
@@ -129,58 +130,38 @@ pub enum CodexErr {

 #[derive(Debug)]
 pub struct UsageLimitReachedError {
-    pub(crate) plan_type: Option<PlanType>,
-    pub(crate) resets_in_seconds: Option<u64>,
+    pub plan_type: Option<String>,
+    pub resets_in_seconds: Option<u64>,
 }

 impl std::fmt::Display for UsageLimitReachedError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        let message = match self.plan_type.as_ref() {
-            Some(PlanType::Known(KnownPlan::Plus)) => format!(
-                "You've hit your usage limit. Upgrade to Pro (https://openai.com/chatgpt/pricing){}",
-                retry_suffix_after_or(self.resets_in_seconds)
-            ),
-            Some(PlanType::Known(KnownPlan::Team)) | Some(PlanType::Known(KnownPlan::Business)) => {
-                format!(
-                    "You've hit your usage limit. To get more access now, send a request to your admin{}",
-                    retry_suffix_after_or(self.resets_in_seconds)
-                )
+        // Base message differs slightly for legacy ChatGPT Plus plan users.
+        if let Some(plan_type) = &self.plan_type
+            && plan_type == "plus"
+        {
+            write!(
+                f,
+                "You've hit your usage limit. Upgrade to Pro (https://openai.com/chatgpt/pricing) or try again"
+            )?;
+            if let Some(secs) = self.resets_in_seconds {
+                let reset_duration = format_reset_duration(secs);
+                write!(f, " in {reset_duration}.")?;
+            } else {
+                write!(f, " later.")?;
            }
-            Some(PlanType::Known(KnownPlan::Free)) => {
-                "To use Codex with your ChatGPT plan, upgrade to Plus: https://openai.com/chatgpt/pricing."
-                    .to_string()
+        } else {
+            write!(f, "You've hit your usage limit.")?;
+
+            if let Some(secs) = self.resets_in_seconds {
+                let reset_duration = format_reset_duration(secs);
+                write!(f, " Try again in {reset_duration}.")?;
+            } else {
+                write!(f, " Try again later.")?;
            }
-            Some(PlanType::Known(KnownPlan::Pro))
-            | Some(PlanType::Known(KnownPlan::Enterprise))
-            | Some(PlanType::Known(KnownPlan::Edu)) => format!(
-                "You've hit your usage limit.{}",
-                retry_suffix(self.resets_in_seconds)
-            ),
-            Some(PlanType::Unknown(_)) | None => format!(
-                "You've hit your usage limit.{}",
-                retry_suffix(self.resets_in_seconds)
-            ),
-        };
+        }

-        write!(f, "{message}")
-    }
-}
-
-fn retry_suffix(resets_in_seconds: Option<u64>) -> String {
-    if let Some(secs) = resets_in_seconds {
-        let reset_duration = format_reset_duration(secs);
-        format!(" Try again in {reset_duration}.")
-    } else {
-        " Try again later.".to_string()
-    }
-}
-
-fn retry_suffix_after_or(resets_in_seconds: Option<u64>) -> String {
-    if let Some(secs) = resets_in_seconds {
-        let reset_duration = format_reset_duration(secs);
-        format!(" or try again in {reset_duration}.")
-    } else {
-        " or try again later.".to_string()
+        Ok(())
    }
 }

@@ -259,7 +240,7 @@ mod tests {
    #[test]
    fn usage_limit_reached_error_formats_plus_plan() {
        let err = UsageLimitReachedError {
-            plan_type: Some(PlanType::Known(KnownPlan::Plus)),
+            plan_type: Some("plus".to_string()),
            resets_in_seconds: None,
        };
        assert_eq!(
@@ -268,18 +249,6 @@ mod tests {
        );
    }

-    #[test]
-    fn usage_limit_reached_error_formats_free_plan() {
-        let err = UsageLimitReachedError {
-            plan_type: Some(PlanType::Known(KnownPlan::Free)),
-            resets_in_seconds: Some(3600),
-        };
-        assert_eq!(
-            err.to_string(),
-            "To use Codex with your ChatGPT plan, upgrade to Plus: https://openai.com/chatgpt/pricing."
-        );
-    }
-
    #[test]
    fn usage_limit_reached_error_formats_default_when_none() {
        let err = UsageLimitReachedError {
@@ -292,34 +261,10 @@ mod tests {
        );
    }

-    #[test]
-    fn usage_limit_reached_error_formats_team_plan() {
-        let err = UsageLimitReachedError {
-            plan_type: Some(PlanType::Known(KnownPlan::Team)),
-            resets_in_seconds: Some(3600),
-        };
-        assert_eq!(
-            err.to_string(),
-            "You've hit your usage limit. To get more access now, send a request to your admin or try again in 1 hour."
-        );
-    }
-
-    #[test]
-    fn usage_limit_reached_error_formats_business_plan_without_reset() {
-        let err = UsageLimitReachedError {
-            plan_type: Some(PlanType::Known(KnownPlan::Business)),
-            resets_in_seconds: None,
-        };
-        assert_eq!(
-            err.to_string(),
-            "You've hit your usage limit. To get more access now, send a request to your admin or try again later."
-        );
-    }
-
    #[test]
    fn usage_limit_reached_error_formats_default_for_other_plans() {
        let err = UsageLimitReachedError {
-            plan_type: Some(PlanType::Known(KnownPlan::Pro)),
+            plan_type: Some("pro".to_string()),
            resets_in_seconds: None,
        };
        assert_eq!(
@@ -343,7 +288,7 @@ mod tests {
    #[test]
    fn usage_limit_reached_includes_hours_and_minutes() {
        let err = UsageLimitReachedError {
-            plan_type: Some(PlanType::Known(KnownPlan::Plus)),
+            plan_type: Some("plus".to_string()),
            resets_in_seconds: Some(3 * 3600 + 32 * 60),
        };
        assert_eq!(
--- a/codex-rs/core/src/event_mapping.rs
+++ b/codex-rs/core/src/event_mapping.rs
@@ -25,56 +25,31 @@ pub(crate) fn map_response_item_to_event_messages(
                return Vec::new();
            }

-            let mut events: Vec<EventMsg> = Vec::new();
-            let mut message_parts: Vec<String> = Vec::new();
-            let mut images: Vec<String> = Vec::new();
-            let mut kind: Option<InputMessageKind> = None;
-
-            for content_item in content.iter() {
-                match content_item {
-                    ContentItem::InputText { text } => {
-                        if kind.is_none() {
-                            let trimmed = text.trim_start();
-                            kind = if trimmed.starts_with("<environment_context>") {
-                                Some(InputMessageKind::EnvironmentContext)
-                            } else if trimmed.starts_with("<user_instructions>") {
-                                Some(InputMessageKind::UserInstructions)
-                            } else {
-                                Some(InputMessageKind::Plain)
-                            };
-                        }
-                        message_parts.push(text.clone());
-                    }
-                    ContentItem::InputImage { image_url } => {
-                        images.push(image_url.clone());
-                    }
+            let events: Vec<EventMsg> = content
+                .iter()
+                .filter_map(|content_item| match content_item {
                    ContentItem::OutputText { text } => {
-                        events.push(EventMsg::AgentMessage(AgentMessageEvent {
+                        Some(EventMsg::AgentMessage(AgentMessageEvent {
                            message: text.clone(),
-                        }));
+                        }))
                    }
-                }
-            }
-
-            if !message_parts.is_empty() || !images.is_empty() {
-                let message = if message_parts.is_empty() {
-                    String::new()
-                } else {
-                    message_parts.join("")
-                };
-                let images = if images.is_empty() {
-                    None
-                } else {
-                    Some(images)
-                };
-
-                events.push(EventMsg::UserMessage(UserMessageEvent {
-                    message,
-                    kind,
-                    images,
-                }));
-            }
-
+                    ContentItem::InputText { text } => {
+                        let trimmed = text.trim_start();
+                        let kind = if trimmed.starts_with("<environment_context>") {
+                            Some(InputMessageKind::EnvironmentContext)
+                        } else if trimmed.starts_with("<user_instructions>") {
+                            Some(InputMessageKind::UserInstructions)
+                        } else {
+                            Some(InputMessageKind::Plain)
+                        };
+                        Some(EventMsg::UserMessage(UserMessageEvent {
+                            message: text.clone(),
+                            kind,
+                        }))
+                    }
+                    _ => None,
+                })
+                .collect();
            events
        }

@@ -121,47 +96,3 @@ pub(crate) fn map_response_item_to_event_messages(
        | ResponseItem::Other => Vec::new(),
    }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::map_response_item_to_event_messages;
-    use crate::protocol::EventMsg;
-    use crate::protocol::InputMessageKind;
-    use codex_protocol::models::ContentItem;
-    use codex_protocol::models::ResponseItem;
-    use pretty_assertions::assert_eq;
-
-    #[test]
-    fn maps_user_message_with_text_and_two_images() {
-        let img1 = "https://example.com/one.png".to_string();
-        let img2 = "https://example.com/two.jpg".to_string();
-
-        let item = ResponseItem::Message {
-            id: None,
-            role: "user".to_string(),
-            content: vec![
-                ContentItem::InputText {
-                    text: "Hello world".to_string(),
-                },
-                ContentItem::InputImage {
-                    image_url: img1.clone(),
-                },
-                ContentItem::InputImage {
-                    image_url: img2.clone(),
-                },
-            ],
-        };
-
-        let events = map_response_item_to_event_messages(&item, false);
-        assert_eq!(events.len(), 1, "expected a single user message event");
-
-        match &events[0] {
-            EventMsg::UserMessage(user) => {
-                assert_eq!(user.message, "Hello world");
-                assert!(matches!(user.kind, Some(InputMessageKind::Plain)));
-                assert_eq!(user.images, Some(vec![img1, img2]));
-            }
-            other => panic!("expected UserMessage, got {other:?}"),
-        }
-    }
-}
--- a/codex-rs/core/src/exec_command/exec_command_session.rs
+++ b/codex-rs/core/src/exec_command/exec_command_session.rs
@@ -24,9 +24,6 @@ pub(crate) struct ExecCommandSession {

    /// JoinHandle for the child wait task.
    wait_handle: StdMutex<Option<JoinHandle<()>>>,
-
-    /// Tracks whether the underlying process has exited.
-    exit_status: std::sync::Arc<std::sync::atomic::AtomicBool>,
 }

 impl ExecCommandSession {
@@ -37,7 +34,6 @@ impl ExecCommandSession {
        reader_handle: JoinHandle<()>,
        writer_handle: JoinHandle<()>,
        wait_handle: JoinHandle<()>,
-        exit_status: std::sync::Arc<std::sync::atomic::AtomicBool>,
    ) -> Self {
        Self {
            writer_tx,
@@ -46,7 +42,6 @@ impl ExecCommandSession {
            reader_handle: StdMutex::new(Some(reader_handle)),
            writer_handle: StdMutex::new(Some(writer_handle)),
            wait_handle: StdMutex::new(Some(wait_handle)),
-            exit_status,
        }
    }

@@ -57,10 +52,6 @@ impl ExecCommandSession {
    pub(crate) fn output_receiver(&self) -> broadcast::Receiver<Vec<u8>> {
        self.output_tx.subscribe()
    }
-
-    pub(crate) fn has_exited(&self) -> bool {
-        self.exit_status.load(std::sync::atomic::Ordering::SeqCst)
-    }
 }

 impl Drop for ExecCommandSession {
--- a/codex-rs/core/src/exec_command/mod.rs
+++ b/codex-rs/core/src/exec_command/mod.rs
@@ -6,7 +6,6 @@ mod session_manager;

 pub use exec_command_params::ExecCommandParams;
 pub use exec_command_params::WriteStdinParams;
-pub(crate) use exec_command_session::ExecCommandSession;
 pub use responses_api::EXEC_COMMAND_TOOL_NAME;
 pub use responses_api::WRITE_STDIN_TOOL_NAME;
 pub use responses_api::create_exec_command_tool_for_responses_api;
--- a/codex-rs/core/src/exec_command/session_manager.rs
+++ b/codex-rs/core/src/exec_command/session_manager.rs
@@ -3,7 +3,6 @@ use std::io::ErrorKind;
 use std::io::Read;
 use std::sync::Arc;
 use std::sync::Mutex as StdMutex;
-use std::sync::atomic::AtomicBool;
 use std::sync::atomic::AtomicU32;

 use portable_pty::CommandBuilder;
@@ -20,7 +19,6 @@ use crate::exec_command::exec_command_params::ExecCommandParams;
 use crate::exec_command::exec_command_params::WriteStdinParams;
 use crate::exec_command::exec_command_session::ExecCommandSession;
 use crate::exec_command::session_id::SessionId;
-use crate::truncate::truncate_middle;
 use codex_protocol::models::FunctionCallOutputPayload;

 #[derive(Debug, Default)]
@@ -329,14 +327,11 @@ async fn create_exec_command_session(

    // Keep the child alive until it exits, then signal exit code.
    let (exit_tx, exit_rx) = oneshot::channel::<i32>();
-    let exit_status = Arc::new(AtomicBool::new(false));
-    let wait_exit_status = exit_status.clone();
    let wait_handle = tokio::task::spawn_blocking(move || {
        let code = match child.wait() {
            Ok(status) => status.exit_code() as i32,
            Err(_) => -1,
        };
-        wait_exit_status.store(true, std::sync::atomic::Ordering::SeqCst);
        let _ = exit_tx.send(code);
    });

@@ -348,11 +343,116 @@ async fn create_exec_command_session(
        reader_handle,
        writer_handle,
        wait_handle,
-        exit_status,
    );
    Ok((session, exit_rx))
 }

+/// Truncate the middle of a UTF-8 string to at most `max_bytes` bytes,
+/// preserving the beginning and the end. Returns the possibly truncated
+/// string and `Some(original_token_count)` (estimated at 4 bytes/token)
+/// if truncation occurred; otherwise returns the original string and `None`.
+fn truncate_middle(s: &str, max_bytes: usize) -> (String, Option<u64>) {
+    // No truncation needed
+    if s.len() <= max_bytes {
+        return (s.to_string(), None);
+    }
+    let est_tokens = (s.len() as u64).div_ceil(4);
+    if max_bytes == 0 {
+        // Cannot keep any content; still return a full marker (never truncated).
+        return (format!("…{est_tokens} tokens truncated…"), Some(est_tokens));
+    }
+
+    // Helper to truncate a string to a given byte length on a char boundary.
+    fn truncate_on_boundary(input: &str, max_len: usize) -> &str {
+        if input.len() <= max_len {
+            return input;
+        }
+        let mut end = max_len;
+        while end > 0 && !input.is_char_boundary(end) {
+            end -= 1;
+        }
+        &input[..end]
+    }
+
+    // Given a left/right budget, prefer newline boundaries; otherwise fall back
+    // to UTF-8 char boundaries.
+    fn pick_prefix_end(s: &str, left_budget: usize) -> usize {
+        if let Some(head) = s.get(..left_budget)
+            && let Some(i) = head.rfind('\n')
+        {
+            return i + 1; // keep the newline so suffix starts on a fresh line
+        }
+        truncate_on_boundary(s, left_budget).len()
+    }
+
+    fn pick_suffix_start(s: &str, right_budget: usize) -> usize {
+        let start_tail = s.len().saturating_sub(right_budget);
+        if let Some(tail) = s.get(start_tail..)
+            && let Some(i) = tail.find('\n')
+        {
+            return start_tail + i + 1; // start after newline
+        }
+        // Fall back to a char boundary at or after start_tail.
+        let mut idx = start_tail.min(s.len());
+        while idx < s.len() && !s.is_char_boundary(idx) {
+            idx += 1;
+        }
+        idx
+    }
+
+    // Refine marker length and budgets until stable. Marker is never truncated.
+    let mut guess_tokens = est_tokens; // worst-case: everything truncated
+    for _ in 0..4 {
+        let marker = format!("…{guess_tokens} tokens truncated…");
+        let marker_len = marker.len();
+        let keep_budget = max_bytes.saturating_sub(marker_len);
+        if keep_budget == 0 {
+            // No room for any content within the cap; return a full, untruncated marker
+            // that reflects the entire truncated content.
+            return (format!("…{est_tokens} tokens truncated…"), Some(est_tokens));
+        }
+
+        let left_budget = keep_budget / 2;
+        let right_budget = keep_budget - left_budget;
+        let prefix_end = pick_prefix_end(s, left_budget);
+        let mut suffix_start = pick_suffix_start(s, right_budget);
+        if suffix_start < prefix_end {
+            suffix_start = prefix_end;
+        }
+        let kept_content_bytes = prefix_end + (s.len() - suffix_start);
+        let truncated_content_bytes = s.len().saturating_sub(kept_content_bytes);
+        let new_tokens = (truncated_content_bytes as u64).div_ceil(4);
+        if new_tokens == guess_tokens {
+            let mut out = String::with_capacity(marker_len + kept_content_bytes + 1);
+            out.push_str(&s[..prefix_end]);
+            out.push_str(&marker);
+            // Place marker on its own line for symmetry when we keep line boundaries.
+            out.push('\n');
+            out.push_str(&s[suffix_start..]);
+            return (out, Some(est_tokens));
+        }
+        guess_tokens = new_tokens;
+    }
+
+    // Fallback: use last guess to build output.
+    let marker = format!("…{guess_tokens} tokens truncated…");
+    let marker_len = marker.len();
+    let keep_budget = max_bytes.saturating_sub(marker_len);
+    if keep_budget == 0 {
+        return (format!("…{est_tokens} tokens truncated…"), Some(est_tokens));
+    }
+    let left_budget = keep_budget / 2;
+    let right_budget = keep_budget - left_budget;
+    let prefix_end = pick_prefix_end(s, left_budget);
+    let suffix_start = pick_suffix_start(s, right_budget);
+    let mut out = String::with_capacity(marker_len + prefix_end + (s.len() - suffix_start) + 1);
+    out.push_str(&s[..prefix_end]);
+    out.push_str(&marker);
+    out.push('\n');
+    out.push_str(&s[suffix_start..]);
+    (out, Some(est_tokens))
+}
+
 #[cfg(test)]
 mod tests {
    use super::*;
@@ -516,4 +616,50 @@ Output:
 abc"#;
        assert_eq!(expected, text);
    }
+
+    #[test]
+    fn truncate_middle_no_newlines_fallback() {
+        // A long string with no newlines that exceeds the cap.
+        let s = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+        let max_bytes = 16; // force truncation
+        let (out, original) = truncate_middle(s, max_bytes);
+        // For very small caps, we return the full, untruncated marker,
+        // even if it exceeds the cap.
+        assert_eq!(out, "…16 tokens truncated…");
+        // Original string length is 62 bytes => ceil(62/4) = 16 tokens.
+        assert_eq!(original, Some(16));
+    }
+
+    #[test]
+    fn truncate_middle_prefers_newline_boundaries() {
+        // Build a multi-line string of 20 numbered lines (each "NNN\n").
+        let mut s = String::new();
+        for i in 1..=20 {
+            s.push_str(&format!("{i:03}\n"));
+        }
+        // Total length: 20 lines * 4 bytes per line = 80 bytes.
+        assert_eq!(s.len(), 80);
+
+        // Choose a cap that forces truncation while leaving room for
+        // a few lines on each side after accounting for the marker.
+        let max_bytes = 64;
+        // Expect exact output: first 4 lines, marker, last 4 lines, and correct token estimate (80/4 = 20).
+        assert_eq!(
+            truncate_middle(&s, max_bytes),
+            (
+                r#"001
+002
+003
+004
+…12 tokens truncated…
+017
+018
+019
+020
+"#
+                .to_string(),
+                Some(20)
+            )
+        );
+    }
 }
--- a/codex-rs/core/src/git_info.rs
+++ b/codex-rs/core/src/git_info.rs
@@ -3,7 +3,6 @@ use std::path::Path;
 use std::path::PathBuf;

 use codex_protocol::mcp_protocol::GitSha;
-use codex_protocol::protocol::GitInfo;
 use futures::future::join_all;
 use serde::Deserialize;
 use serde::Serialize;
@@ -44,6 +43,19 @@ pub fn get_git_repo_root(base_dir: &Path) -> Option<PathBuf> {
 /// Timeout for git commands to prevent freezing on large repositories
 const GIT_COMMAND_TIMEOUT: TokioDuration = TokioDuration::from_secs(5);

+#[derive(Serialize, Deserialize, Clone, Debug)]
+pub struct GitInfo {
+    /// Current commit hash (SHA)
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub commit_hash: Option<String>,
+    /// Current branch name
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub branch: Option<String>,
+    /// Repository URL (if available from remote)
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub repository_url: Option<String>,
+}
+
 #[derive(Serialize, Deserialize, Clone, Debug)]
 pub struct GitDiffToRemote {
    pub sha: GitSha,
@@ -802,7 +814,7 @@ mod tests {
    async fn resolve_root_git_project_for_trust_regular_repo_returns_repo_root() {
        let temp_dir = TempDir::new().expect("Failed to create temp dir");
        let repo_path = create_test_git_repo(&temp_dir).await;
-        let expected = std::fs::canonicalize(&repo_path).unwrap();
+        let expected = std::fs::canonicalize(&repo_path).unwrap().to_path_buf();

        assert_eq!(
            resolve_root_git_project_for_trust(&repo_path),
@@ -810,7 +822,10 @@ mod tests {
        );
        let nested = repo_path.join("sub/dir");
        std::fs::create_dir_all(&nested).unwrap();
-        assert_eq!(resolve_root_git_project_for_trust(&nested), Some(expected));
+        assert_eq!(
+            resolve_root_git_project_for_trust(&nested),
+            Some(expected.clone())
+        );
    }

    #[tokio::test]
--- a/codex-rs/core/src/internal_storage.rs
+++ b/codex-rs/core/src/internal_storage.rs
@@ -1,68 +0,0 @@
-use anyhow::Context;
-use serde::Deserialize;
-use serde::Serialize;
-use std::path::Path;
-use std::path::PathBuf;
-
-pub(crate) const INTERNAL_STORAGE_FILE: &str = "internal_storage.json";
-
-#[derive(Debug, Default, Clone, Serialize, Deserialize)]
-pub struct InternalStorage {
-    #[serde(skip)]
-    storage_path: PathBuf,
-    #[serde(default)]
-    pub gpt_5_high_model_prompt_seen: bool,
-}
-
-// TODO(jif) generalise all the file writers and build proper async channel inserters.
-impl InternalStorage {
-    pub fn load(codex_home: &Path) -> Self {
-        let storage_path = codex_home.join(INTERNAL_STORAGE_FILE);
-
-        match std::fs::read_to_string(&storage_path) {
-            Ok(serialized) => match serde_json::from_str::<Self>(&serialized) {
-                Ok(mut storage) => {
-                    storage.storage_path = storage_path;
-                    storage
-                }
-                Err(error) => {
-                    tracing::warn!("failed to parse internal storage: {error:?}");
-                    Self::empty(storage_path)
-                }
-            },
-            Err(error) => {
-                tracing::warn!("failed to read internal storage: {error:?}");
-                Self::empty(storage_path)
-            }
-        }
-    }
-
-    fn empty(storage_path: PathBuf) -> Self {
-        Self {
-            storage_path,
-            ..Default::default()
-        }
-    }
-
-    pub async fn persist(&self) -> anyhow::Result<()> {
-        let serialized = serde_json::to_string_pretty(self)?;
-
-        if let Some(parent) = self.storage_path.parent() {
-            tokio::fs::create_dir_all(parent).await.with_context(|| {
-                format!(
-                    "failed to create internal storage directory at {}",
-                    parent.display()
-                )
-            })?;
-        }
-
-        tokio::fs::write(&self.storage_path, serialized)
-            .await
-            .with_context(|| {
-                format!(
-                    "failed to persist internal storage at {}",
-                    self.storage_path.display()
-                )
-            })
-    }
-}
--- a/codex-rs/core/src/lib.rs
+++ b/codex-rs/core/src/lib.rs
@@ -16,7 +16,6 @@ mod codex_conversation;
 pub mod token_data;
 pub use codex_conversation::CodexConversation;
 pub mod config;
-pub mod config_edit;
 pub mod config_profile;
 pub mod config_types;
 mod conversation_history;
@@ -28,7 +27,6 @@ mod exec_command;
 pub mod exec_env;
 mod flags;
 pub mod git_info;
-pub mod internal_storage;
 mod is_safe_command;
 pub mod landlock;
 mod mcp_connection_manager;
@@ -36,8 +34,6 @@ mod mcp_tool_call;
 mod message_history;
 mod model_provider_info;
 pub mod parse_command;
-mod truncate;
-mod unified_exec;
 mod user_instructions;
 pub use model_provider_info::BUILT_IN_OSS_MODEL_PROVIDER_ID;
 pub use model_provider_info::ModelProviderInfo;
@@ -46,7 +42,6 @@ pub use model_provider_info::built_in_model_providers;
 pub use model_provider_info::create_oss_provider_with_base_url;
 mod conversation_manager;
 mod event_mapping;
-pub use codex_protocol::protocol::InitialHistory;
 pub use conversation_manager::ConversationManager;
 pub use conversation_manager::NewConversation;
 // Re-export common auth types for workspace consumers
@@ -66,16 +61,13 @@ pub mod spawn;
 pub mod terminal;
 mod tool_apply_patch;
 pub mod turn_diff_tracker;
-pub use rollout::ARCHIVED_SESSIONS_SUBDIR;
 pub use rollout::RolloutRecorder;
-pub use rollout::SESSIONS_SUBDIR;
 pub use rollout::SessionMeta;
 pub use rollout::list::ConversationItem;
 pub use rollout::list::ConversationsPage;
 pub use rollout::list::Cursor;
 mod user_notification;
 pub mod util;
-
 pub use apply_patch::CODEX_APPLY_PATCH_ARG1;
 pub use safety::get_platform_sandbox;
 // Re-export the protocol types from the standalone `codex-protocol` crate so existing
--- a/codex-rs/core/src/mcp_connection_manager.rs
+++ b/codex-rs/core/src/mcp_connection_manager.rs
@@ -163,10 +163,6 @@ impl McpConnectionManager {
                                name: "codex-mcp-client".to_owned(),
                                version: env!("CARGO_PKG_VERSION").to_owned(),
                                title: Some("Codex".into()),
-                                // This field is used by Codex when it is an MCP
-                                // server: it should not be used when Codex is
-                                // an MCP client.
-                                user_agent: None,
                            },
                            protocol_version: mcp_types::MCP_SCHEMA_VERSION.to_owned(),
                        };
--- a/codex-rs/core/src/model_family.rs
+++ b/codex-rs/core/src/model_family.rs
@@ -103,7 +103,7 @@ pub fn find_family_for_model(slug: &str) -> Option<ModelFamily> {
            slug, "gpt-4.1",
            needs_special_apply_patch_instructions: true,
        )
-    } else if slug.starts_with("gpt-oss") || slug.starts_with("openai/gpt-oss") {
+    } else if slug.starts_with("gpt-oss") {
        model_family!(slug, "gpt-oss", apply_patch_tool_type: Some(ApplyPatchToolType::Function))
    } else if slug.starts_with("gpt-4o") {
        simple_model_family!(slug, "gpt-4o")
--- a/codex-rs/core/src/model_provider_info.rs
+++ b/codex-rs/core/src/model_provider_info.rs
@@ -80,10 +80,7 @@ pub struct ModelProviderInfo {
    /// the connection as lost.
    pub stream_idle_timeout_ms: Option<u64>,

-    /// Does this provider require an OpenAI API Key or ChatGPT login token? If true,
-    /// user is presented with login screen on first run, and login preference and token/key
-    /// are stored in auth.json. If false (which is the default), login screen is skipped,
-    /// and API key (if needed) comes from the "env_key" environment variable.
+    /// Whether this provider requires some form of standard authentication (API key, ChatGPT token).
    #[serde(default)]
    pub requires_openai_auth: bool,
 }
--- a/codex-rs/core/src/openai_model_info.rs
+++ b/codex-rs/core/src/openai_model_info.rs
@@ -78,7 +78,7 @@ pub(crate) fn get_model_info(model_family: &ModelFamily) -> Option<ModelInfo> {
            max_output_tokens: 4_096,
        }),

-        _ if slug.starts_with("gpt-5") => Some(ModelInfo {
+        "gpt-5" => Some(ModelInfo {
            context_window: 272_000,
            max_output_tokens: 128_000,
        }),
--- a/codex-rs/core/src/openai_tools.rs
+++ b/codex-rs/core/src/openai_tools.rs
@@ -8,6 +8,7 @@ use std::collections::HashMap;
 use crate::model_family::ModelFamily;
 use crate::plan_tool::PLAN_TOOL;
 use crate::protocol::AskForApproval;
+use crate::protocol::SandboxPolicy;
 use crate::tool_apply_patch::ApplyPatchToolType;
 use crate::tool_apply_patch::create_apply_patch_freeform_tool;
 use crate::tool_apply_patch::create_apply_patch_json_tool;
@@ -57,7 +58,7 @@ pub(crate) enum OpenAiTool {
 #[derive(Debug, Clone)]
 pub enum ConfigShellToolType {
    DefaultShell,
-    ShellWithRequest,
+    ShellWithRequest { sandbox_policy: SandboxPolicy },
    LocalShell,
    StreamableShell,
 }
@@ -69,18 +70,17 @@ pub(crate) struct ToolsConfig {
    pub apply_patch_tool_type: Option<ApplyPatchToolType>,
    pub web_search_request: bool,
    pub include_view_image_tool: bool,
-    pub experimental_unified_exec_tool: bool,
 }

 pub(crate) struct ToolsConfigParams<'a> {
    pub(crate) model_family: &'a ModelFamily,
    pub(crate) approval_policy: AskForApproval,
+    pub(crate) sandbox_policy: SandboxPolicy,
    pub(crate) include_plan_tool: bool,
    pub(crate) include_apply_patch_tool: bool,
    pub(crate) include_web_search_request: bool,
    pub(crate) use_streamable_shell_tool: bool,
    pub(crate) include_view_image_tool: bool,
-    pub(crate) experimental_unified_exec_tool: bool,
 }

 impl ToolsConfig {
@@ -88,12 +88,12 @@ impl ToolsConfig {
        let ToolsConfigParams {
            model_family,
            approval_policy,
+            sandbox_policy,
            include_plan_tool,
            include_apply_patch_tool,
            include_web_search_request,
            use_streamable_shell_tool,
            include_view_image_tool,
-            experimental_unified_exec_tool,
        } = params;
        let mut shell_type = if *use_streamable_shell_tool {
            ConfigShellToolType::StreamableShell
@@ -103,7 +103,9 @@ impl ToolsConfig {
            ConfigShellToolType::DefaultShell
        };
        if matches!(approval_policy, AskForApproval::OnRequest) && !use_streamable_shell_tool {
-            shell_type = ConfigShellToolType::ShellWithRequest;
+            shell_type = ConfigShellToolType::ShellWithRequest {
+                sandbox_policy: sandbox_policy.clone(),
+            }
        }

        let apply_patch_tool_type = match model_family.apply_patch_tool_type {
@@ -124,7 +126,6 @@ impl ToolsConfig {
            apply_patch_tool_type,
            web_search_request: *include_web_search_request,
            include_view_image_tool: *include_view_image_tool,
-            experimental_unified_exec_tool: *experimental_unified_exec_tool,
        }
    }
 }
@@ -199,56 +200,7 @@ fn create_shell_tool() -> OpenAiTool {
    })
 }

-fn create_unified_exec_tool() -> OpenAiTool {
-    let mut properties = BTreeMap::new();
-    properties.insert(
-        "input".to_string(),
-        JsonSchema::Array {
-            items: Box::new(JsonSchema::String { description: None }),
-            description: Some(
-                "When no session_id is provided, treat the array as the command and arguments \
-                 to launch. When session_id is set, concatenate the strings (in order) and write \
-                 them to the session's stdin."
-                    .to_string(),
-            ),
-        },
-    );
-    properties.insert(
-        "session_id".to_string(),
-        JsonSchema::String {
-            description: Some(
-                "Identifier for an existing interactive session. If omitted, a new command \
-                 is spawned."
-                    .to_string(),
-            ),
-        },
-    );
-    properties.insert(
-        "timeout_ms".to_string(),
-        JsonSchema::Number {
-            description: Some(
-                "Maximum time in milliseconds to wait for output after writing the input."
-                    .to_string(),
-            ),
-        },
-    );
-
-    OpenAiTool::Function(ResponsesApiTool {
-        name: "unified_exec".to_string(),
-        description:
-            "Runs a command in a PTY. Provide a session_id to reuse an existing interactive session.".to_string(),
-        strict: false,
-        parameters: JsonSchema::Object {
-            properties,
-            required: Some(vec!["input".to_string()]),
-            additional_properties: Some(false),
-        },
-    })
-}
-
-const SHELL_TOOL_DESCRIPTION: &str = r#"Runs a shell command and returns its output"#;
-
-fn create_shell_tool_for_request() -> OpenAiTool {
+fn create_shell_tool_for_sandbox(sandbox_policy: &SandboxPolicy) -> OpenAiTool {
    let mut properties = BTreeMap::new();
    properties.insert(
        "command".to_string(),
@@ -260,29 +212,82 @@ fn create_shell_tool_for_request() -> OpenAiTool {
    properties.insert(
        "workdir".to_string(),
        JsonSchema::String {
-            description: Some("Working directory to execute the command in.".to_string()),
+            description: Some("The working directory to execute the command in".to_string()),
        },
    );
    properties.insert(
        "timeout_ms".to_string(),
        JsonSchema::Number {
-            description: Some("Timeout for the command in milliseconds.".to_string()),
-        },
-    );
-    properties.insert(
-        "with_escalated_permissions".to_string(),
-        JsonSchema::Boolean {
-            description: Some("Request escalated permissions, only for when a command would otherwise be blocked by the sandbox.".to_string()),
-        },
-    );
-    properties.insert(
-        "justification".to_string(),
-        JsonSchema::String {
-            description: Some("Required if and only if with_escalated_permissions == true. One sentence explaining why escalation is needed (e.g., write outside CWD, network fetch, git commit).".to_string()),
+            description: Some("The timeout for the command in milliseconds".to_string()),
        },
    );

-    let description = SHELL_TOOL_DESCRIPTION.to_string();
+    if matches!(sandbox_policy, SandboxPolicy::WorkspaceWrite { .. }) {
+        properties.insert(
+        "with_escalated_permissions".to_string(),
+        JsonSchema::Boolean {
+            description: Some("Whether to request escalated permissions. Set to true if command needs to be run without sandbox restrictions".to_string()),
+        },
+    );
+        properties.insert(
+        "justification".to_string(),
+        JsonSchema::String {
+            description: Some("Only set if with_escalated_permissions is true. 1-sentence explanation of why we want to run this command.".to_string()),
+        },
+    );
+    }
+
+    let description = match sandbox_policy {
+        SandboxPolicy::WorkspaceWrite {
+            network_access,
+            writable_roots,
+            ..
+        } => {
+            format!(
+                r#"
+The shell tool is used to execute shell commands.
+- When invoking the shell tool, your call will be running in a sandbox, and some shell commands will require escalated privileges:
+  - Types of actions that require escalated privileges:
+    - Writing files other than those in the writable roots
+      - writable roots:
+{}{}
+  - Examples of commands that require escalated privileges:
+    - git commit
+    - npm install or pnpm install
+    - cargo build
+    - cargo test
+- When invoking a command that will require escalated privileges:
+  - Provide the with_escalated_permissions parameter with the boolean value true
+  - Include a short, 1 sentence explanation for why we need to run with_escalated_permissions in the justification parameter."#,
+                writable_roots.iter().map(|wr| format!("        - {}", wr.to_string_lossy())).collect::<Vec<String>>().join("\n"),
+                if !network_access {
+                    "\n    - Commands that require network access\n"
+                } else {
+                    ""
+                }
+            )
+        }
+        SandboxPolicy::DangerFullAccess => {
+            "Runs a shell command and returns its output.".to_string()
+        }
+        SandboxPolicy::ReadOnly => {
+            r#"
+The shell tool is used to execute shell commands.
+- When invoking the shell tool, your call will be running in a sandbox, and some shell commands (including apply_patch) will require escalated permissions:
+  - Types of actions that require escalated privileges:
+    - Writing files
+    - Applying patches
+  - Examples of commands that require escalated privileges:
+    - apply_patch
+    - git commit
+    - npm install or pnpm install
+    - cargo build
+    - cargo test
+- When invoking a command that will require escalated privileges:
+  - Provide the with_escalated_permissions parameter with the boolean value true
+  - Include a short, 1 sentence explanation for why we need to run with_escalated_permissions in the justification parameter"#.to_string()
+        }
+    };

    OpenAiTool::Function(ResponsesApiTool {
        name: "shell".to_string(),
@@ -295,6 +300,7 @@ fn create_shell_tool_for_request() -> OpenAiTool {
        },
    })
 }
+
 fn create_view_image_tool() -> OpenAiTool {
    // Support only local filesystem path.
    let mut properties = BTreeMap::new();
@@ -528,27 +534,23 @@ pub(crate) fn get_openai_tools(
 ) -> Vec<OpenAiTool> {
    let mut tools: Vec<OpenAiTool> = Vec::new();

-    if config.experimental_unified_exec_tool {
-        tools.push(create_unified_exec_tool());
-    } else {
-        match &config.shell_type {
-            ConfigShellToolType::DefaultShell => {
-                tools.push(create_shell_tool());
-            }
-            ConfigShellToolType::ShellWithRequest => {
-                tools.push(create_shell_tool_for_request());
-            }
-            ConfigShellToolType::LocalShell => {
-                tools.push(OpenAiTool::LocalShell {});
-            }
-            ConfigShellToolType::StreamableShell => {
-                tools.push(OpenAiTool::Function(
-                    crate::exec_command::create_exec_command_tool_for_responses_api(),
-                ));
-                tools.push(OpenAiTool::Function(
-                    crate::exec_command::create_write_stdin_tool_for_responses_api(),
-                ));
-            }
+    match &config.shell_type {
+        ConfigShellToolType::DefaultShell => {
+            tools.push(create_shell_tool());
+        }
+        ConfigShellToolType::ShellWithRequest { sandbox_policy } => {
+            tools.push(create_shell_tool_for_sandbox(sandbox_policy));
+        }
+        ConfigShellToolType::LocalShell => {
+            tools.push(OpenAiTool::LocalShell {});
+        }
+        ConfigShellToolType::StreamableShell => {
+            tools.push(OpenAiTool::Function(
+                crate::exec_command::create_exec_command_tool_for_responses_api(),
+            ));
+            tools.push(OpenAiTool::Function(
+                crate::exec_command::create_write_stdin_tool_for_responses_api(),
+            ));
        }
    }

@@ -575,8 +577,10 @@ pub(crate) fn get_openai_tools(
    if config.include_view_image_tool {
        tools.push(create_view_image_tool());
    }
+
    if let Some(mcp_tools) = mcp_tools {
        // Ensure deterministic ordering to maximize prompt cache hits.
+        // HashMap iteration order is non-deterministic, so sort by fully-qualified tool name.
        let mut entries: Vec<(String, mcp_types::Tool)> = mcp_tools.into_iter().collect();
        entries.sort_by(|a, b| a.0.cmp(&b.0));

@@ -632,18 +636,18 @@ mod tests {
        let config = ToolsConfig::new(&ToolsConfigParams {
            model_family: &model_family,
            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::ReadOnly,
            include_plan_tool: true,
            include_apply_patch_tool: false,
            include_web_search_request: true,
            use_streamable_shell_tool: false,
            include_view_image_tool: true,
-            experimental_unified_exec_tool: true,
        });
        let tools = get_openai_tools(&config, Some(HashMap::new()));

        assert_eq_tool_names(
            &tools,
-            &["unified_exec", "update_plan", "web_search", "view_image"],
+            &["local_shell", "update_plan", "web_search", "view_image"],
        );
    }

@@ -653,18 +657,18 @@ mod tests {
        let config = ToolsConfig::new(&ToolsConfigParams {
            model_family: &model_family,
            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::ReadOnly,
            include_plan_tool: true,
            include_apply_patch_tool: false,
            include_web_search_request: true,
            use_streamable_shell_tool: false,
            include_view_image_tool: true,
-            experimental_unified_exec_tool: true,
        });
        let tools = get_openai_tools(&config, Some(HashMap::new()));

        assert_eq_tool_names(
            &tools,
-            &["unified_exec", "update_plan", "web_search", "view_image"],
+            &["shell", "update_plan", "web_search", "view_image"],
        );
    }

@@ -674,12 +678,12 @@ mod tests {
        let config = ToolsConfig::new(&ToolsConfigParams {
            model_family: &model_family,
            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::ReadOnly,
            include_plan_tool: false,
            include_apply_patch_tool: false,
            include_web_search_request: true,
            use_streamable_shell_tool: false,
            include_view_image_tool: true,
-            experimental_unified_exec_tool: true,
        });
        let tools = get_openai_tools(
            &config,
@@ -722,7 +726,7 @@ mod tests {
        assert_eq_tool_names(
            &tools,
            &[
-                "unified_exec",
+                "shell",
                "web_search",
                "view_image",
                "test_server/do_something_cool",
@@ -779,12 +783,12 @@ mod tests {
        let config = ToolsConfig::new(&ToolsConfigParams {
            model_family: &model_family,
            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::ReadOnly,
            include_plan_tool: false,
            include_apply_patch_tool: false,
            include_web_search_request: false,
            use_streamable_shell_tool: false,
            include_view_image_tool: true,
-            experimental_unified_exec_tool: true,
        });

        // Intentionally construct a map with keys that would sort alphabetically.
@@ -837,11 +841,11 @@ mod tests {
        ]);

        let tools = get_openai_tools(&config, Some(tools_map));
-        // Expect unified_exec first, followed by MCP tools sorted by fully-qualified name.
+        // Expect shell first, followed by MCP tools sorted by fully-qualified name.
        assert_eq_tool_names(
            &tools,
            &[
-                "unified_exec",
+                "shell",
                "view_image",
                "test_server/cool",
                "test_server/do",
@@ -856,12 +860,12 @@ mod tests {
        let config = ToolsConfig::new(&ToolsConfigParams {
            model_family: &model_family,
            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::ReadOnly,
            include_plan_tool: false,
            include_apply_patch_tool: false,
            include_web_search_request: true,
            use_streamable_shell_tool: false,
            include_view_image_tool: true,
-            experimental_unified_exec_tool: true,
        });

        let tools = get_openai_tools(
@@ -889,7 +893,7 @@ mod tests {

        assert_eq_tool_names(
            &tools,
-            &["unified_exec", "web_search", "view_image", "dash/search"],
+            &["shell", "web_search", "view_image", "dash/search"],
        );

        assert_eq!(
@@ -918,12 +922,12 @@ mod tests {
        let config = ToolsConfig::new(&ToolsConfigParams {
            model_family: &model_family,
            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::ReadOnly,
            include_plan_tool: false,
            include_apply_patch_tool: false,
            include_web_search_request: true,
            use_streamable_shell_tool: false,
            include_view_image_tool: true,
-            experimental_unified_exec_tool: true,
        });

        let tools = get_openai_tools(
@@ -949,7 +953,7 @@ mod tests {

        assert_eq_tool_names(
            &tools,
-            &["unified_exec", "web_search", "view_image", "dash/paginate"],
+            &["shell", "web_search", "view_image", "dash/paginate"],
        );
        assert_eq!(
            tools[3],
@@ -975,12 +979,12 @@ mod tests {
        let config = ToolsConfig::new(&ToolsConfigParams {
            model_family: &model_family,
            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::ReadOnly,
            include_plan_tool: false,
            include_apply_patch_tool: false,
            include_web_search_request: true,
            use_streamable_shell_tool: false,
            include_view_image_tool: true,
-            experimental_unified_exec_tool: true,
        });

        let tools = get_openai_tools(
@@ -1004,10 +1008,7 @@ mod tests {
            )])),
        );

-        assert_eq_tool_names(
-            &tools,
-            &["unified_exec", "web_search", "view_image", "dash/tags"],
-        );
+        assert_eq_tool_names(&tools, &["shell", "web_search", "view_image", "dash/tags"]);
        assert_eq!(
            tools[3],
            OpenAiTool::Function(ResponsesApiTool {
@@ -1035,12 +1036,12 @@ mod tests {
        let config = ToolsConfig::new(&ToolsConfigParams {
            model_family: &model_family,
            approval_policy: AskForApproval::Never,
+            sandbox_policy: SandboxPolicy::ReadOnly,
            include_plan_tool: false,
            include_apply_patch_tool: false,
            include_web_search_request: true,
            use_streamable_shell_tool: false,
            include_view_image_tool: true,
-            experimental_unified_exec_tool: true,
        });

        let tools = get_openai_tools(
@@ -1064,10 +1065,7 @@ mod tests {
            )])),
        );

-        assert_eq_tool_names(
-            &tools,
-            &["unified_exec", "web_search", "view_image", "dash/value"],
-        );
+        assert_eq_tool_names(&tools, &["shell", "web_search", "view_image", "dash/value"]);
        assert_eq!(
            tools[3],
            OpenAiTool::Function(ResponsesApiTool {
@@ -1088,7 +1086,13 @@ mod tests {

    #[test]
    fn test_shell_tool_for_sandbox_workspace_write() {
-        let tool = super::create_shell_tool_for_request();
+        let sandbox_policy = SandboxPolicy::WorkspaceWrite {
+            writable_roots: vec!["workspace".into()],
+            network_access: false,
+            exclude_tmpdir_env_var: false,
+            exclude_slash_tmp: false,
+        };
+        let tool = super::create_shell_tool_for_sandbox(&sandbox_policy);
        let OpenAiTool::Function(ResponsesApiTool {
            description, name, ..
        }) = &tool
@@ -1097,13 +1101,29 @@ mod tests {
        };
        assert_eq!(name, "shell");

-        let expected = super::SHELL_TOOL_DESCRIPTION;
+        let expected = r#"
+The shell tool is used to execute shell commands.
+- When invoking the shell tool, your call will be running in a sandbox, and some shell commands will require escalated privileges:
+  - Types of actions that require escalated privileges:
+    - Writing files other than those in the writable roots
+      - writable roots:
+        - workspace
+    - Commands that require network access
+
+  - Examples of commands that require escalated privileges:
+    - git commit
+    - npm install or pnpm install
+    - cargo build
+    - cargo test
+- When invoking a command that will require escalated privileges:
+  - Provide the with_escalated_permissions parameter with the boolean value true
+  - Include a short, 1 sentence explanation for why we need to run with_escalated_permissions in the justification parameter."#;
        assert_eq!(description, expected);
    }

    #[test]
    fn test_shell_tool_for_sandbox_readonly() {
-        let tool = super::create_shell_tool_for_request();
+        let tool = super::create_shell_tool_for_sandbox(&SandboxPolicy::ReadOnly);
        let OpenAiTool::Function(ResponsesApiTool {
            description, name, ..
        }) = &tool
@@ -1112,13 +1132,27 @@ mod tests {
        };
        assert_eq!(name, "shell");

-        let expected = super::SHELL_TOOL_DESCRIPTION;
+        let expected = r#"
+The shell tool is used to execute shell commands.
+- When invoking the shell tool, your call will be running in a sandbox, and some shell commands (including apply_patch) will require escalated permissions:
+  - Types of actions that require escalated privileges:
+    - Writing files
+    - Applying patches
+  - Examples of commands that require escalated privileges:
+    - apply_patch
+    - git commit
+    - npm install or pnpm install
+    - cargo build
+    - cargo test
+- When invoking a command that will require escalated privileges:
+  - Provide the with_escalated_permissions parameter with the boolean value true
+  - Include a short, 1 sentence explanation for why we need to run with_escalated_permissions in the justification parameter"#;
        assert_eq!(description, expected);
    }

    #[test]
    fn test_shell_tool_for_sandbox_danger_full_access() {
-        let tool = super::create_shell_tool_for_request();
+        let tool = super::create_shell_tool_for_sandbox(&SandboxPolicy::DangerFullAccess);
        let OpenAiTool::Function(ResponsesApiTool {
            description, name, ..
        }) = &tool
@@ -1127,7 +1161,6 @@ mod tests {
        };
        assert_eq!(name, "shell");

-        let expected = super::SHELL_TOOL_DESCRIPTION;
-        assert_eq!(description, expected);
+        assert_eq!(description, "Runs a shell command and returns its output.");
    }
 }
--- a/codex-rs/core/src/parse_command.rs
+++ b/codex-rs/core/src/parse_command.rs
@@ -868,7 +868,7 @@ pub fn parse_command_impl(command: &[String]) -> Vec<ParsedCommand> {
    let parts = if contains_connectors(&normalized) {
        split_on_connectors(&normalized)
    } else {
-        vec![normalized]
+        vec![normalized.clone()]
    };

    // Preserve left-to-right execution order for all commands, including bash -c/-lc
@@ -1201,7 +1201,10 @@ fn parse_bash_lc_commands(original: &[String]) -> Option<Vec<ParsedCommand>> {
                                    name,
                                }
                            } else {
-                                ParsedCommand::Read { cmd, name }
+                                ParsedCommand::Read {
+                                    cmd: cmd.clone(),
+                                    name,
+                                }
                            }
                        } else {
                            ParsedCommand::Read {
@@ -1212,7 +1215,10 @@ fn parse_bash_lc_commands(original: &[String]) -> Option<Vec<ParsedCommand>> {
                    }
                    ParsedCommand::ListFiles { path, cmd, .. } => {
                        if had_connectors {
-                            ParsedCommand::ListFiles { cmd, path }
+                            ParsedCommand::ListFiles {
+                                cmd: cmd.clone(),
+                                path,
+                            }
                        } else {
                            ParsedCommand::ListFiles {
                                cmd: shlex_join(&script_tokens),
@@ -1224,7 +1230,11 @@ fn parse_bash_lc_commands(original: &[String]) -> Option<Vec<ParsedCommand>> {
                        query, path, cmd, ..
                    } => {
                        if had_connectors {
-                            ParsedCommand::Search { cmd, query, path }
+                            ParsedCommand::Search {
+                                cmd: cmd.clone(),
+                                query,
+                                path,
+                            }
                        } else {
                            ParsedCommand::Search {
                                cmd: shlex_join(&script_tokens),
--- a/codex-rs/core/src/project_doc.rs
+++ b/codex-rs/core/src/project_doc.rs
@@ -26,7 +26,7 @@ const PROJECT_DOC_SEPARATOR: &str = "\n\n--- project-doc ---\n\n";

 /// Combines `Config::instructions` and `AGENTS.md` (if present) into a single
 /// string of instructions.
-pub async fn get_user_instructions(config: &Config) -> Option<String> {
+pub(crate) async fn get_user_instructions(config: &Config) -> Option<String> {
    match read_project_docs(config).await {
        Ok(Some(project_doc)) => match &config.user_instructions {
            Some(original_instructions) => Some(format!(
@@ -115,7 +115,7 @@ pub fn discover_project_doc_paths(config: &Config) -> std::io::Result<Vec<PathBu
    // Build chain from cwd upwards and detect git root.
    let mut chain: Vec<PathBuf> = vec![dir.clone()];
    let mut git_root: Option<PathBuf> = None;
-    let mut cursor = dir;
+    let mut cursor = dir.clone();
    while let Some(parent) = cursor.parent() {
        let git_marker = cursor.join(".git");
        let git_exists = match std::fs::metadata(&git_marker) {
--- a/codex-rs/core/src/rollout/list.rs
+++ b/codex-rs/core/src/rollout/list.rs
@@ -10,9 +10,6 @@ use time::macros::format_description;
 use uuid::Uuid;

 use super::SESSIONS_SUBDIR;
-use crate::protocol::EventMsg;
-use codex_protocol::protocol::RolloutItem;
-use codex_protocol::protocol::RolloutLine;

 /// Returned page of conversation summaries.
 #[derive(Debug, Default, PartialEq)]
@@ -37,7 +34,7 @@ pub struct ConversationItem {
 }

 /// Hard cap to bound worst‑case work per request.
-const MAX_SCAN_FILES: usize = 100;
+const MAX_SCAN_FILES: usize = 10_000;
 const HEAD_RECORD_LIMIT: usize = 10;

 /// Pagination cursor identifying a file by timestamp and UUID.
@@ -170,16 +167,10 @@ async fn traverse_directories_for_paths(
                    if items.len() == page_size {
                        break 'outer;
                    }
-                    // Read head and simultaneously detect message events within the same
-                    // first N JSONL records to avoid a second file read.
-                    let (head, saw_session_meta, saw_user_event) =
-                        read_head_and_flags(&path, HEAD_RECORD_LIMIT)
-                            .await
-                            .unwrap_or((Vec::new(), false, false));
-                    // Apply filters: must have session meta and at least one user message event
-                    if saw_session_meta && saw_user_event {
-                        items.push(ConversationItem { path, head });
-                    }
+                    let head = read_first_jsonl_records(&path, HEAD_RECORD_LIMIT)
+                        .await
+                        .unwrap_or_default();
+                    items.push(ConversationItem { path, head });
                }
            }
        }
@@ -282,19 +273,16 @@ fn parse_timestamp_uuid_from_filename(name: &str) -> Option<(OffsetDateTime, Uui
    Some((ts, uuid))
 }

-async fn read_head_and_flags(
+async fn read_first_jsonl_records(
    path: &Path,
    max_records: usize,
-) -> io::Result<(Vec<serde_json::Value>, bool, bool)> {
+) -> io::Result<Vec<serde_json::Value>> {
    use tokio::io::AsyncBufReadExt;

    let file = tokio::fs::File::open(path).await?;
    let reader = tokio::io::BufReader::new(file);
    let mut lines = reader.lines();
    let mut head: Vec<serde_json::Value> = Vec::new();
-    let mut saw_session_meta = false;
-    let mut saw_user_event = false;
-
    while head.len() < max_records {
        let line_opt = lines.next_line().await?;
        let Some(line) = line_opt else { break };
@@ -302,35 +290,9 @@ async fn read_head_and_flags(
        if trimmed.is_empty() {
            continue;
        }
-
-        let parsed: Result<RolloutLine, _> = serde_json::from_str(trimmed);
-        let Ok(rollout_line) = parsed else { continue };
-
-        match rollout_line.item {
-            RolloutItem::SessionMeta(session_meta_line) => {
-                if let Ok(val) = serde_json::to_value(session_meta_line) {
-                    head.push(val);
-                    saw_session_meta = true;
-                }
-            }
-            RolloutItem::ResponseItem(item) => {
-                if let Ok(val) = serde_json::to_value(item) {
-                    head.push(val);
-                }
-            }
-            RolloutItem::TurnContext(_) => {
-                // Not included in `head`; skip.
-            }
-            RolloutItem::Compacted(_) => {
-                // Not included in `head`; skip.
-            }
-            RolloutItem::EventMsg(ev) => {
-                if matches!(ev, EventMsg::UserMessage(_)) {
-                    saw_user_event = true;
-                }
-            }
+        if let Ok(v) = serde_json::from_str::<serde_json::Value>(trimmed) {
+            head.push(v);
        }
    }
-
-    Ok((head, saw_session_meta, saw_user_event))
+    Ok(head)
 }
--- a/codex-rs/core/src/rollout/mod.rs
+++ b/codex-rs/core/src/rollout/mod.rs
@@ -1,15 +1,15 @@
 //! Rollout module: persistence and discovery of session rollout files.

-pub const SESSIONS_SUBDIR: &str = "sessions";
-pub const ARCHIVED_SESSIONS_SUBDIR: &str = "archived_sessions";
+pub(crate) const SESSIONS_SUBDIR: &str = "sessions";

 pub mod list;
 pub(crate) mod policy;
 pub mod recorder;

-pub use codex_protocol::protocol::SessionMeta;
 pub use recorder::RolloutRecorder;
 pub use recorder::RolloutRecorderParams;
+pub use recorder::SessionMeta;
+pub use recorder::SessionStateSnapshot;

 #[cfg(test)]
 pub mod tests;
--- a/codex-rs/core/src/rollout/policy.rs
+++ b/codex-rs/core/src/rollout/policy.rs
@@ -1,23 +1,8 @@
-use crate::protocol::EventMsg;
-use crate::protocol::RolloutItem;
 use codex_protocol::models::ResponseItem;

-/// Whether a rollout `item` should be persisted in rollout files.
-#[inline]
-pub(crate) fn is_persisted_response_item(item: &RolloutItem) -> bool {
-    match item {
-        RolloutItem::ResponseItem(item) => should_persist_response_item(item),
-        RolloutItem::EventMsg(ev) => should_persist_event_msg(ev),
-        // Persist Codex executive markers so we can analyze flows (e.g., compaction, API turns).
-        RolloutItem::Compacted(_) | RolloutItem::TurnContext(_) | RolloutItem::SessionMeta(_) => {
-            true
-        }
-    }
-}
-
 /// Whether a `ResponseItem` should be persisted in rollout files.
 #[inline]
-pub(crate) fn should_persist_response_item(item: &ResponseItem) -> bool {
+pub(crate) fn is_persisted_response_item(item: &ResponseItem) -> bool {
    match item {
        ResponseItem::Message { .. }
        | ResponseItem::Reasoning { .. }
@@ -29,44 +14,3 @@ pub(crate) fn should_persist_response_item(item: &ResponseItem) -> bool {
        ResponseItem::WebSearchCall { .. } | ResponseItem::Other => false,
    }
 }
-
-/// Whether an `EventMsg` should be persisted in rollout files.
-#[inline]
-pub(crate) fn should_persist_event_msg(ev: &EventMsg) -> bool {
-    match ev {
-        EventMsg::UserMessage(_)
-        | EventMsg::AgentMessage(_)
-        | EventMsg::AgentReasoning(_)
-        | EventMsg::AgentReasoningRawContent(_)
-        | EventMsg::TokenCount(_) => true,
-        EventMsg::Error(_)
-        | EventMsg::TaskStarted(_)
-        | EventMsg::TaskComplete(_)
-        | EventMsg::AgentMessageDelta(_)
-        | EventMsg::AgentReasoningDelta(_)
-        | EventMsg::AgentReasoningRawContentDelta(_)
-        | EventMsg::AgentReasoningSectionBreak(_)
-        | EventMsg::SessionConfigured(_)
-        | EventMsg::McpToolCallBegin(_)
-        | EventMsg::McpToolCallEnd(_)
-        | EventMsg::WebSearchBegin(_)
-        | EventMsg::WebSearchEnd(_)
-        | EventMsg::ExecCommandBegin(_)
-        | EventMsg::ExecCommandOutputDelta(_)
-        | EventMsg::ExecCommandEnd(_)
-        | EventMsg::ExecApprovalRequest(_)
-        | EventMsg::ApplyPatchApprovalRequest(_)
-        | EventMsg::BackgroundEvent(_)
-        | EventMsg::StreamError(_)
-        | EventMsg::PatchApplyBegin(_)
-        | EventMsg::PatchApplyEnd(_)
-        | EventMsg::TurnDiff(_)
-        | EventMsg::GetHistoryEntryResponse(_)
-        | EventMsg::McpListToolsResponse(_)
-        | EventMsg::ListCustomPromptsResponse(_)
-        | EventMsg::PlanUpdate(_)
-        | EventMsg::TurnAborted(_)
-        | EventMsg::ShutdownComplete
-        | EventMsg::ConversationPath(_) => false,
-    }
-}
--- a/codex-rs/core/src/rollout/recorder.rs
+++ b/codex-rs/core/src/rollout/recorder.rs
@@ -26,15 +26,26 @@ use super::list::Cursor;
 use super::list::get_conversations;
 use super::policy::is_persisted_response_item;
 use crate::config::Config;
-use crate::default_client::ORIGINATOR;
+use crate::conversation_manager::InitialHistory;
+use crate::conversation_manager::ResumedHistory;
+use crate::git_info::GitInfo;
 use crate::git_info::collect_git_info;
 use codex_protocol::models::ResponseItem;
-use codex_protocol::protocol::InitialHistory;
-use codex_protocol::protocol::ResumedHistory;
-use codex_protocol::protocol::RolloutItem;
-use codex_protocol::protocol::RolloutLine;
-use codex_protocol::protocol::SessionMeta;
-use codex_protocol::protocol::SessionMetaLine;
+
+#[derive(Serialize, Deserialize, Clone, Default)]
+pub struct SessionMeta {
+    pub id: ConversationId,
+    pub timestamp: String,
+    pub instructions: Option<String>,
+}
+
+#[derive(Serialize)]
+struct SessionMetaWithGit {
+    #[serde(flatten)]
+    meta: SessionMeta,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    git: Option<GitInfo>,
+}

 #[derive(Serialize, Deserialize, Default, Clone)]
 pub struct SessionStateSnapshot {}
@@ -61,7 +72,6 @@ pub struct SavedSession {
 #[derive(Clone)]
 pub struct RolloutRecorder {
    tx: Sender<RolloutCmd>,
-    pub(crate) rollout_path: PathBuf,
 }

 #[derive(Clone)]
@@ -76,14 +86,9 @@ pub enum RolloutRecorderParams {
 }

 enum RolloutCmd {
-    AddItems(Vec<RolloutItem>),
-    /// Ensure all prior writes are processed; respond when flushed.
-    Flush {
-        ack: oneshot::Sender<()>,
-    },
-    Shutdown {
-        ack: oneshot::Sender<()>,
-    },
+    AddItems(Vec<ResponseItem>),
+    UpdateState(SessionStateSnapshot),
+    Shutdown { ack: oneshot::Sender<()> },
 }

 impl RolloutRecorderParams {
@@ -100,6 +105,7 @@ impl RolloutRecorderParams {
 }

 impl RolloutRecorder {
+    #[allow(dead_code)]
    /// List conversations (rollout files) under the provided Codex home directory.
    pub async fn list_conversations(
        codex_home: &Path,
@@ -113,14 +119,13 @@ impl RolloutRecorder {
    /// cannot be created or the rollout file cannot be opened we return the
    /// error so the caller can decide whether to disable persistence.
    pub async fn new(config: &Config, params: RolloutRecorderParams) -> std::io::Result<Self> {
-        let (file, rollout_path, meta) = match params {
+        let (file, meta) = match params {
            RolloutRecorderParams::Create {
                conversation_id,
                instructions,
            } => {
                let LogFileInfo {
                    file,
-                    path,
                    conversation_id: session_id,
                    timestamp,
                } = create_log_file(config, conversation_id)?;
@@ -135,13 +140,9 @@ impl RolloutRecorder {

                (
                    tokio::fs::File::from_std(file),
-                    path,
                    Some(SessionMeta {
-                        id: session_id,
                        timestamp,
-                        cwd: config.cwd.clone(),
-                        originator: ORIGINATOR.value.clone(),
-                        cli_version: env!("CARGO_PKG_VERSION").to_string(),
+                        id: session_id,
                        instructions,
                    }),
                )
@@ -149,9 +150,8 @@ impl RolloutRecorder {
            RolloutRecorderParams::Resume { path } => (
                tokio::fs::OpenOptions::new()
                    .append(true)
-                    .open(&path)
+                    .open(path)
                    .await?,
-                path,
                None,
            ),
        };
@@ -169,10 +169,10 @@ impl RolloutRecorder {
        // driver instead of blocking the runtime.
        tokio::task::spawn(rollout_writer(file, rx, meta, cwd));

-        Ok(Self { tx, rollout_path })
+        Ok(Self { tx })
    }

-    pub(crate) async fn record_items(&self, items: &[RolloutItem]) -> std::io::Result<()> {
+    pub(crate) async fn record_items(&self, items: &[ResponseItem]) -> std::io::Result<()> {
        let mut filtered = Vec::new();
        for item in items {
            // Note that function calls may look a bit strange if they are
@@ -191,65 +191,60 @@ impl RolloutRecorder {
            .map_err(|e| IoError::other(format!("failed to queue rollout items: {e}")))
    }

-    /// Flush all queued writes and wait until they are committed by the writer task.
-    pub async fn flush(&self) -> std::io::Result<()> {
-        let (tx, rx) = oneshot::channel();
+    pub(crate) async fn record_state(&self, state: SessionStateSnapshot) -> std::io::Result<()> {
        self.tx
-            .send(RolloutCmd::Flush { ack: tx })
+            .send(RolloutCmd::UpdateState(state))
            .await
-            .map_err(|e| IoError::other(format!("failed to queue rollout flush: {e}")))?;
-        rx.await
-            .map_err(|e| IoError::other(format!("failed waiting for rollout flush: {e}")))
+            .map_err(|e| IoError::other(format!("failed to queue rollout state: {e}")))
    }

-    pub(crate) async fn get_rollout_history(path: &Path) -> std::io::Result<InitialHistory> {
+    pub async fn get_rollout_history(path: &Path) -> std::io::Result<InitialHistory> {
        info!("Resuming rollout from {path:?}");
        tracing::error!("Resuming rollout from {path:?}");
        let text = tokio::fs::read_to_string(path).await?;
-        if text.trim().is_empty() {
-            return Err(IoError::other("empty session file"));
-        }
+        let mut lines = text.lines();
+        let first_line = lines
+            .next()
+            .ok_or_else(|| IoError::other("empty session file"))?;
+        let conversation_id = match serde_json::from_str::<SessionMeta>(first_line) {
+            Ok(rollout_session_meta) => {
+                tracing::error!(
+                    "Parsed conversation ID from rollout file: {:?}",
+                    rollout_session_meta.id
+                );
+                Some(rollout_session_meta.id)
+            }
+            Err(e) => {
+                return Err(IoError::other(format!(
+                    "failed to parse first line of rollout file as SessionMeta: {e}"
+                )));
+            }
+        };

-        let mut items: Vec<RolloutItem> = Vec::new();
-        let mut conversation_id: Option<ConversationId> = None;
-        for line in text.lines() {
+        let mut items = Vec::new();
+        for line in lines {
            if line.trim().is_empty() {
                continue;
            }
            let v: Value = match serde_json::from_str(line) {
                Ok(v) => v,
-                Err(e) => {
-                    warn!("failed to parse line as JSON: {line:?}, error: {e}");
-                    continue;
-                }
+                Err(_) => continue,
            };
-
-            // Parse the rollout line structure
-            match serde_json::from_value::<RolloutLine>(v.clone()) {
-                Ok(rollout_line) => match rollout_line.item {
-                    RolloutItem::SessionMeta(session_meta_line) => {
-                        // Use the FIRST SessionMeta encountered in the file as the canonical
-                        // conversation id and main session information. Keep all items intact.
-                        if conversation_id.is_none() {
-                            conversation_id = Some(session_meta_line.meta.id);
-                        }
-                        items.push(RolloutItem::SessionMeta(session_meta_line));
+            if v.get("record_type")
+                .and_then(|rt| rt.as_str())
+                .map(|s| s == "state")
+                .unwrap_or(false)
+            {
+                continue;
+            }
+            match serde_json::from_value::<ResponseItem>(v.clone()) {
+                Ok(item) => {
+                    if is_persisted_response_item(&item) {
+                        items.push(item);
                    }
-                    RolloutItem::ResponseItem(item) => {
-                        items.push(RolloutItem::ResponseItem(item));
-                    }
-                    RolloutItem::Compacted(item) => {
-                        items.push(RolloutItem::Compacted(item));
-                    }
-                    RolloutItem::TurnContext(item) => {
-                        items.push(RolloutItem::TurnContext(item));
-                    }
-                    RolloutItem::EventMsg(_ev) => {
-                        items.push(RolloutItem::EventMsg(_ev));
-                    }
-                },
+                }
                Err(e) => {
-                    warn!("failed to parse rollout line: {v:?}, error: {e}");
+                    warn!("failed to parse item: {v:?}, error: {e}");
                }
            }
        }
@@ -274,10 +269,6 @@ impl RolloutRecorder {
        }))
    }

-    pub(crate) fn get_rollout_path(&self) -> PathBuf {
-        self.rollout_path.clone()
-    }
-
    pub async fn shutdown(&self) -> std::io::Result<()> {
        let (tx_done, rx_done) = oneshot::channel();
        match self.tx.send(RolloutCmd::Shutdown { ack: tx_done }).await {
@@ -298,9 +289,6 @@ struct LogFileInfo {
    /// Opened file handle to the rollout file.
    file: File,

-    /// Full path to the rollout file.
-    path: PathBuf,
-
    /// Session ID (also embedded in filename).
    conversation_id: ConversationId,

@@ -340,7 +328,6 @@ fn create_log_file(

    Ok(LogFileInfo {
        file,
-        path,
        conversation_id,
        timestamp,
    })
@@ -357,15 +344,13 @@ async fn rollout_writer(
    // If we have a meta, collect git info asynchronously and write meta first
    if let Some(session_meta) = meta.take() {
        let git_info = collect_git_info(&cwd).await;
-        let session_meta_line = SessionMetaLine {
+        let session_meta_with_git = SessionMetaWithGit {
            meta: session_meta,
            git: git_info,
        };

-        // Write the SessionMeta as the first item in the file, wrapped in a rollout line
-        writer
-            .write_rollout_item(RolloutItem::SessionMeta(session_meta_line))
-            .await?;
+        // Write the SessionMeta as the first item in the file
+        writer.write_line(&session_meta_with_git).await?;
    }

    // Process rollout commands
@@ -374,17 +359,23 @@ async fn rollout_writer(
            RolloutCmd::AddItems(items) => {
                for item in items {
                    if is_persisted_response_item(&item) {
-                        writer.write_rollout_item(item).await?;
+                        writer.write_line(&item).await?;
                    }
                }
            }
-            RolloutCmd::Flush { ack } => {
-                // Ensure underlying file is flushed and then ack.
-                if let Err(e) = writer.file.flush().await {
-                    let _ = ack.send(());
-                    return Err(e);
+            RolloutCmd::UpdateState(state) => {
+                #[derive(Serialize)]
+                struct StateLine<'a> {
+                    record_type: &'static str,
+                    #[serde(flatten)]
+                    state: &'a SessionStateSnapshot,
                }
-                let _ = ack.send(());
+                writer
+                    .write_line(&StateLine {
+                        record_type: "state",
+                        state: &state,
+                    })
+                    .await?;
            }
            RolloutCmd::Shutdown { ack } => {
                let _ = ack.send(());
@@ -400,20 +391,6 @@ struct JsonlWriter {
 }

 impl JsonlWriter {
-    async fn write_rollout_item(&mut self, rollout_item: RolloutItem) -> std::io::Result<()> {
-        let timestamp_format: &[FormatItem] = format_description!(
-            "[year]-[month]-[day]T[hour]:[minute]:[second].[subsecond digits:3]Z"
-        );
-        let timestamp = OffsetDateTime::now_utc()
-            .format(timestamp_format)
-            .map_err(|e| IoError::other(format!("failed to format timestamp: {e}")))?;
-
-        let line = RolloutLine {
-            timestamp,
-            item: rollout_item,
-        };
-        self.write_line(&line).await
-    }
    async fn write_line(&mut self, item: &impl serde::Serialize) -> std::io::Result<()> {
        let mut json = serde_json::to_string(item)?;
        json.push('\n');
--- a/codex-rs/core/src/rollout/tests.rs
+++ b/codex-rs/core/src/rollout/tests.rs
@@ -42,30 +42,10 @@ fn write_session_file(

    let meta = serde_json::json!({
        "timestamp": ts_str,
-        "type": "session_meta",
-        "payload": {
-            "id": uuid,
-            "timestamp": ts_str,
-            "instructions": null,
-            "cwd": ".",
-            "originator": "test_originator",
-            "cli_version": "test_version"
-        }
+        "id": uuid.to_string()
    });
    writeln!(file, "{meta}")?;

-    // Include at least one user message event to satisfy listing filters
-    let user_event = serde_json::json!({
-        "timestamp": ts_str,
-        "type": "event_msg",
-        "payload": {
-            "type": "user_message",
-            "message": "Hello from user",
-            "kind": "plain"
-        }
-    });
-    writeln!(file, "{user_event}")?;
-
    for i in 0..num_records {
        let rec = serde_json::json!({
            "record_type": "response",
@@ -113,30 +93,24 @@ async fn test_list_conversations_latest_first() {
        .join("01")
        .join(format!("rollout-2025-01-01T12-00-00-{u1}.jsonl"));

-    let head_3 = vec![serde_json::json!({
-        "id": u3,
-        "timestamp": "2025-01-03T12-00-00",
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
-    let head_2 = vec![serde_json::json!({
-        "id": u2,
-        "timestamp": "2025-01-02T12-00-00",
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
-    let head_1 = vec![serde_json::json!({
-        "id": u1,
-        "timestamp": "2025-01-01T12-00-00",
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
+    let head_3 = vec![
+        serde_json::json!({"timestamp": "2025-01-03T12-00-00", "id": u3.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+        serde_json::json!({"record_type": "response", "index": 1}),
+        serde_json::json!({"record_type": "response", "index": 2}),
+    ];
+    let head_2 = vec![
+        serde_json::json!({"timestamp": "2025-01-02T12-00-00", "id": u2.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+        serde_json::json!({"record_type": "response", "index": 1}),
+        serde_json::json!({"record_type": "response", "index": 2}),
+    ];
+    let head_1 = vec![
+        serde_json::json!({"timestamp": "2025-01-01T12-00-00", "id": u1.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+        serde_json::json!({"record_type": "response", "index": 1}),
+        serde_json::json!({"record_type": "response", "index": 2}),
+    ];

    let expected_cursor: Cursor =
        serde_json::from_str(&format!("\"2025-01-01T12-00-00|{u1}\"")).unwrap();
@@ -196,22 +170,14 @@ async fn test_pagination_cursor() {
        .join("03")
        .join("04")
        .join(format!("rollout-2025-03-04T09-00-00-{u4}.jsonl"));
-    let head_5 = vec![serde_json::json!({
-        "id": u5,
-        "timestamp": "2025-03-05T09-00-00",
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
-    let head_4 = vec![serde_json::json!({
-        "id": u4,
-        "timestamp": "2025-03-04T09-00-00",
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
+    let head_5 = vec![
+        serde_json::json!({"timestamp": "2025-03-05T09-00-00", "id": u5.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+    ];
+    let head_4 = vec![
+        serde_json::json!({"timestamp": "2025-03-04T09-00-00", "id": u4.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+    ];
    let expected_cursor1: Cursor =
        serde_json::from_str(&format!("\"2025-03-04T09-00-00|{u4}\"")).unwrap();
    let expected_page1 = ConversationsPage {
@@ -246,22 +212,14 @@ async fn test_pagination_cursor() {
        .join("03")
        .join("02")
        .join(format!("rollout-2025-03-02T09-00-00-{u2}.jsonl"));
-    let head_3 = vec![serde_json::json!({
-        "id": u3,
-        "timestamp": "2025-03-03T09-00-00",
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
-    let head_2 = vec![serde_json::json!({
-        "id": u2,
-        "timestamp": "2025-03-02T09-00-00",
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
+    let head_3 = vec![
+        serde_json::json!({"timestamp": "2025-03-03T09-00-00", "id": u3.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+    ];
+    let head_2 = vec![
+        serde_json::json!({"timestamp": "2025-03-02T09-00-00", "id": u2.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+    ];
    let expected_cursor2: Cursor =
        serde_json::from_str(&format!("\"2025-03-02T09-00-00|{u2}\"")).unwrap();
    let expected_page2 = ConversationsPage {
@@ -290,14 +248,10 @@ async fn test_pagination_cursor() {
        .join("03")
        .join("01")
        .join(format!("rollout-2025-03-01T09-00-00-{u1}.jsonl"));
-    let head_1 = vec![serde_json::json!({
-        "id": u1,
-        "timestamp": "2025-03-01T09-00-00",
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
+    let head_1 = vec![
+        serde_json::json!({"timestamp": "2025-03-01T09-00-00", "id": u1.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+    ];
    let expected_cursor3: Cursor =
        serde_json::from_str(&format!("\"2025-03-01T09-00-00|{u1}\"")).unwrap();
    let expected_page3 = ConversationsPage {
@@ -305,7 +259,7 @@ async fn test_pagination_cursor() {
            path: p1,
            head: head_1,
        }],
-        next_cursor: Some(expected_cursor3),
+        next_cursor: Some(expected_cursor3.clone()),
        num_scanned_files: 5, // scanned 05, 04 (anchor), 03, 02 (anchor), 01
        reached_scan_cap: false,
    };
@@ -333,18 +287,15 @@ async fn test_get_conversation_contents() {
        .join("04")
        .join("01")
        .join(format!("rollout-2025-04-01T10-30-00-{uuid}.jsonl"));
-    let expected_head = vec![serde_json::json!({
-        "id": uuid,
-        "timestamp": ts,
-        "instructions": null,
-        "cwd": ".",
-        "originator": "test_originator",
-        "cli_version": "test_version"
-    })];
+    let expected_head = vec![
+        serde_json::json!({"timestamp": ts, "id": uuid.to_string()}),
+        serde_json::json!({"record_type": "response", "index": 0}),
+        serde_json::json!({"record_type": "response", "index": 1}),
+    ];
    let expected_cursor: Cursor = serde_json::from_str(&format!("\"{ts}|{uuid}\"")).unwrap();
    let expected_page = ConversationsPage {
        items: vec![ConversationItem {
-            path: expected_path,
+            path: expected_path.clone(),
            head: expected_head,
        }],
        next_cursor: Some(expected_cursor),
@@ -354,15 +305,10 @@ async fn test_get_conversation_contents() {
    assert_eq!(page, expected_page);

    // Entire file contents equality
-    let meta = serde_json::json!({"timestamp": ts, "type": "session_meta", "payload": {"id": uuid, "timestamp": ts, "instructions": null, "cwd": ".", "originator": "test_originator", "cli_version": "test_version"}});
-    let user_event = serde_json::json!({
-        "timestamp": ts,
-        "type": "event_msg",
-        "payload": {"type": "user_message", "message": "Hello from user", "kind": "plain"}
-    });
+    let meta = serde_json::json!({"timestamp": ts, "id": uuid.to_string()});
    let rec0 = serde_json::json!({"record_type": "response", "index": 0});
    let rec1 = serde_json::json!({"record_type": "response", "index": 1});
-    let expected_content = format!("{meta}\n{user_event}\n{rec0}\n{rec1}\n");
+    let expected_content = format!("{meta}\n{rec0}\n{rec1}\n");
    assert_eq!(content, expected_content);
 }

@@ -395,14 +341,7 @@ async fn test_stable_ordering_same_second_pagination() {
        .join("01")
        .join(format!("rollout-2025-07-01T00-00-00-{u2}.jsonl"));
    let head = |u: Uuid| -> Vec<serde_json::Value> {
-        vec![serde_json::json!({
-            "id": u,
-            "timestamp": ts,
-            "instructions": null,
-            "cwd": ".",
-            "originator": "test_originator",
-            "cli_version": "test_version"
-        })]
+        vec![serde_json::json!({"timestamp": ts, "id": u.to_string()})]
    };
    let expected_cursor1: Cursor = serde_json::from_str(&format!("\"{ts}|{u2}\"")).unwrap();
    let expected_page1 = ConversationsPage {
@@ -437,7 +376,7 @@ async fn test_stable_ordering_same_second_pagination() {
            path: p1,
            head: head(u1),
        }],
-        next_cursor: Some(expected_cursor2),
+        next_cursor: Some(expected_cursor2.clone()),
        num_scanned_files: 3, // scanned u3, u2 (anchor), u1
        reached_scan_cap: false,
    };
--- a/codex-rs/core/src/safety.rs
+++ b/codex-rs/core/src/safety.rs
@@ -293,7 +293,7 @@ mod tests {
        // With the parent dir explicitly added as a writable root, the
        // outside write should be permitted.
        let policy_with_parent = SandboxPolicy::WorkspaceWrite {
-            writable_roots: vec![parent],
+            writable_roots: vec![parent.clone()],
            network_access: false,
            exclude_tmpdir_env_var: true,
            exclude_slash_tmp: true,
--- a/codex-rs/core/src/seatbelt.rs
+++ b/codex-rs/core/src/seatbelt.rs
@@ -153,7 +153,7 @@ mod tests {
        // Build a policy that only includes the two test roots as writable and
        // does not automatically include defaults TMPDIR or /tmp.
        let policy = SandboxPolicy::WorkspaceWrite {
-            writable_roots: vec![root_with_git, root_without_git],
+            writable_roots: vec![root_with_git.clone(), root_without_git.clone()],
            network_access: false,
            exclude_tmpdir_env_var: true,
            exclude_slash_tmp: true,
--- a/codex-rs/core/src/shell.rs
+++ b/codex-rs/core/src/shell.rs
@@ -1,18 +1,36 @@
 use serde::Deserialize;
 use serde::Serialize;
 use shlex;
+use std::path::Path;
 use std::path::PathBuf;
+use std::sync::Arc;
+use tracing::trace;
+use uuid::Uuid;

-#[derive(Debug, PartialEq, Eq, Clone, Serialize, Deserialize)]
-pub struct ZshShell {
-    shell_path: String,
-    zshrc_path: String,
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
+/// This structure cannot derive Clone or this will break the Drop implementation.
+pub struct ShellSnapshot {
+    pub(crate) path: PathBuf,
+}
+
+impl ShellSnapshot {
+    pub fn new(path: PathBuf) -> Self {
+        Self { path }
+    }
+}
+
+impl Drop for ShellSnapshot {
+    fn drop(&mut self) {
+        delete_shell_snapshot(&self.path);
+    }
 }

 #[derive(Debug, PartialEq, Eq, Clone, Serialize, Deserialize)]
-pub struct BashShell {
-    shell_path: String,
-    bashrc_path: String,
+pub struct PosixShell {
+    pub(crate) shell_path: String,
+    pub(crate) rc_path: String,
+    #[serde(skip_serializing, skip_deserializing)]
+    pub(crate) shell_snapshot: Option<Arc<ShellSnapshot>>,
 }

 #[derive(Debug, PartialEq, Eq, Clone, Serialize, Deserialize)]
@@ -23,8 +41,7 @@ pub struct PowerShellConfig {

 #[derive(Debug, PartialEq, Eq, Clone, Serialize, Deserialize)]
 pub enum Shell {
-    Zsh(ZshShell),
-    Bash(BashShell),
+    Posix(PosixShell),
    PowerShell(PowerShellConfig),
    Unknown,
 }
@@ -32,11 +49,27 @@ pub enum Shell {
 impl Shell {
    pub fn format_default_shell_invocation(&self, command: Vec<String>) -> Option<Vec<String>> {
        match self {
-            Shell::Zsh(zsh) => {
-                format_shell_invocation_with_rc(&command, &zsh.shell_path, &zsh.zshrc_path)
-            }
-            Shell::Bash(bash) => {
-                format_shell_invocation_with_rc(&command, &bash.shell_path, &bash.bashrc_path)
+            Shell::Posix(shell) => {
+                let joined = strip_bash_lc(&command)
+                    .or_else(|| shlex::try_join(command.iter().map(|s| s.as_str())).ok())?;
+
+                let mut source_path = Path::new(&shell.rc_path);
+
+                let session_cmd = if let Some(shell_snapshot) = &shell.shell_snapshot
+                    && shell_snapshot.path.exists()
+                {
+                    source_path = shell_snapshot.path.as_path();
+                    "-c".to_string()
+                } else {
+                    "-lc".to_string()
+                };
+
+                let source_path_str = source_path.to_string_lossy().to_string();
+                let quoted_source_path = shlex::try_quote(&source_path_str).ok()?;
+                let rc_command =
+                    format!("[ -f {quoted_source_path} ] && . {quoted_source_path}; ({joined})");
+
+                Some(vec![shell.shell_path.clone(), session_cmd, rc_command])
            }
            Shell::PowerShell(ps) => {
                // If model generated a bash command, prefer a detected bash fallback
@@ -89,33 +122,20 @@ impl Shell {

    pub fn name(&self) -> Option<String> {
        match self {
-            Shell::Zsh(zsh) => std::path::Path::new(&zsh.shell_path)
-                .file_name()
-                .map(|s| s.to_string_lossy().to_string()),
-            Shell::Bash(bash) => std::path::Path::new(&bash.shell_path)
+            Shell::Posix(shell) => Path::new(&shell.shell_path)
                .file_name()
                .map(|s| s.to_string_lossy().to_string()),
            Shell::PowerShell(ps) => Some(ps.exe.clone()),
            Shell::Unknown => None,
        }
    }
-}

-fn format_shell_invocation_with_rc(
-    command: &Vec<String>,
-    shell_path: &str,
-    rc_path: &str,
-) -> Option<Vec<String>> {
-    let joined = strip_bash_lc(command)
-        .or_else(|| shlex::try_join(command.iter().map(|s| s.as_str())).ok())?;
-
-    let rc_command = if std::path::Path::new(rc_path).exists() {
-        format!("source {rc_path} && ({joined})")
-    } else {
-        joined
-    };
-
-    Some(vec![shell_path.to_string(), "-lc".to_string(), rc_command])
+    pub fn get_snapshot(&self) -> Option<Arc<ShellSnapshot>> {
+        match self {
+            Shell::Posix(shell) => shell.shell_snapshot.clone(),
+            _ => None,
+        }
+    }
 }

 fn strip_bash_lc(command: &Vec<String>) -> Option<String> {
@@ -132,7 +152,7 @@ fn strip_bash_lc(command: &Vec<String>) -> Option<String> {
 }

 #[cfg(unix)]
-fn detect_default_user_shell() -> Shell {
+async fn detect_default_user_shell(session_id: Uuid, codex_home: &Path) -> Shell {
    use libc::getpwuid;
    use libc::getuid;
    use std::ffi::CStr;
@@ -147,31 +167,45 @@ fn detect_default_user_shell() -> Shell {
                .into_owned();
            let home_path = CStr::from_ptr((*pw).pw_dir).to_string_lossy().into_owned();

-            if shell_path.ends_with("/zsh") {
-                return Shell::Zsh(ZshShell {
-                    shell_path,
-                    zshrc_path: format!("{home_path}/.zshrc"),
-                });
-            }
+            let rc_path = if shell_path.ends_with("/zsh") {
+                format!("{home_path}/.zshrc")
+            } else if shell_path.ends_with("/bash") {
+                format!("{home_path}/.bashrc")
+            } else {
+                return Shell::Unknown;
+            };

-            if shell_path.ends_with("/bash") {
-                return Shell::Bash(BashShell {
-                    shell_path,
-                    bashrc_path: format!("{home_path}/.bashrc"),
-                });
+            let snapshot_path = snapshots::ensure_posix_snapshot(
+                &shell_path,
+                &rc_path,
+                Path::new(&home_path),
+                codex_home,
+                session_id,
+            )
+            .await;
+            if snapshot_path.is_none() {
+                trace!("failed to prepare posix snapshot; using live profile");
            }
+            let shell_snapshot =
+                snapshot_path.map(|snapshot| Arc::new(ShellSnapshot::new(snapshot)));
+
+            return Shell::Posix(PosixShell {
+                shell_path,
+                rc_path,
+                shell_snapshot,
+            });
        }
    }
    Shell::Unknown
 }

 #[cfg(unix)]
-pub async fn default_user_shell() -> Shell {
-    detect_default_user_shell()
+pub async fn default_user_shell(session_id: Uuid, codex_home: &Path) -> Shell {
+    detect_default_user_shell(session_id, codex_home).await
 }

 #[cfg(target_os = "windows")]
-pub async fn default_user_shell() -> Shell {
+pub async fn default_user_shell(_session_id: Uuid, _codex_home: &Path) -> Shell {
    use tokio::process::Command;

    // Prefer PowerShell 7+ (`pwsh`) if available, otherwise fall back to Windows PowerShell.
@@ -211,42 +245,158 @@ pub async fn default_user_shell() -> Shell {
 }

 #[cfg(all(not(target_os = "windows"), not(unix)))]
-pub async fn default_user_shell() -> Shell {
+pub async fn default_user_shell(_session_id: Uuid, _codex_home: &Path) -> Shell {
    Shell::Unknown
 }

+#[cfg(unix)]
+mod snapshots {
+    use super::*;
+
+    fn zsh_profile_paths(home: &Path) -> Vec<PathBuf> {
+        [".zshenv", ".zprofile", ".zshrc", ".zlogin"]
+            .into_iter()
+            .map(|name| home.join(name))
+            .collect()
+    }
+
+    fn posix_profile_source_script(home: &Path) -> String {
+        zsh_profile_paths(home)
+            .into_iter()
+            .map(|profile| {
+                let profile_string = profile.to_string_lossy().into_owned();
+                let quoted = shlex::try_quote(&profile_string)
+                    .map(|cow| cow.into_owned())
+                    .unwrap_or(profile_string.clone());
+
+                format!("[ -f {quoted} ] && . {quoted}")
+            })
+            .collect::<Vec<_>>()
+            .join("; ")
+    }
+
+    pub(crate) async fn ensure_posix_snapshot(
+        shell_path: &str,
+        rc_path: &str,
+        home: &Path,
+        codex_home: &Path,
+        session_id: Uuid,
+    ) -> Option<PathBuf> {
+        let snapshot_path = codex_home.join(format!("shell_snapshots/snapshot_{session_id}.zsh"));
+
+        // Check if an update in the profile requires to re-generate the snapshot.
+        let snapshot_is_stale = async {
+            let snapshot_metadata = tokio::fs::metadata(&snapshot_path).await.ok()?;
+            let snapshot_modified = snapshot_metadata.modified().ok()?;
+
+            for profile in zsh_profile_paths(home) {
+                let Ok(profile_metadata) = tokio::fs::metadata(&profile).await else {
+                    continue;
+                };
+
+                let Ok(profile_modified) = profile_metadata.modified() else {
+                    return Some(true);
+                };
+
+                if profile_modified > snapshot_modified {
+                    return Some(true);
+                }
+            }
+
+            Some(false)
+        }
+        .await
+        .unwrap_or(true);
+
+        if !snapshot_is_stale {
+            return Some(snapshot_path);
+        }
+
+        match regenerate_posix_snapshot(shell_path, rc_path, home, &snapshot_path).await {
+            Ok(()) => Some(snapshot_path),
+            Err(err) => {
+                tracing::warn!("failed to generate posix snapshot: {err}");
+                None
+            }
+        }
+    }
+
+    async fn regenerate_posix_snapshot(
+        shell_path: &str,
+        rc_path: &str,
+        home: &Path,
+        snapshot_path: &Path,
+    ) -> std::io::Result<()> {
+        // Use `emulate -L sh` instead of `set -o posix` so we work on zsh builds
+        // that disable that option. Guard `alias -p` with `|| true` so the script
+        // keeps a zero exit status even if aliases are disabled.
+        let mut capture_script = String::new();
+        let profile_sources = posix_profile_source_script(home);
+        if !profile_sources.is_empty() {
+            capture_script.push_str(&format!("{profile_sources}; "));
+        }
+
+        let zshrc = home.join(rc_path);
+
+        capture_script.push_str(
+            &format!(". {}; setopt posixbuiltins; export -p; {{ alias | sed 's/^/alias /'; }} 2>/dev/null || true", zshrc.display()),
+        );
+        let output = tokio::process::Command::new(shell_path)
+            .arg("-lc")
+            .arg(capture_script)
+            .env("HOME", home)
+            .output()
+            .await?;
+
+        if !output.status.success() {
+            return Err(std::io::Error::other(format!(
+                "snapshot capture exited with status {}",
+                output.status
+            )));
+        }
+
+        let mut contents = String::from("# Generated by Codex. Do not edit.\n");
+
+        contents.push_str(&String::from_utf8_lossy(&output.stdout));
+        contents.push('\n');
+
+        if let Some(parent) = snapshot_path.parent() {
+            tokio::fs::create_dir_all(parent).await?;
+        }
+
+        let tmp_path = snapshot_path.with_extension("tmp");
+        tokio::fs::write(&tmp_path, contents).await?;
+
+        // Restrict the snapshot to user read/write so that environment variables or aliases
+        // that may contain secrets are not exposed to other users on the system.
+        use std::os::unix::fs::PermissionsExt;
+        let permissions = std::fs::Permissions::from_mode(0o600);
+        tokio::fs::set_permissions(&tmp_path, permissions).await?;
+
+        tokio::fs::rename(&tmp_path, snapshot_path).await?;
+        Ok(())
+    }
+}
+
+pub(crate) fn delete_shell_snapshot(path: &Path) {
+    if let Err(err) = std::fs::remove_file(path) {
+        trace!("failed to delete shell snapshot {path:?}: {err}");
+    }
+}
+
 #[cfg(test)]
 #[cfg(unix)]
 mod tests {
    use super::*;
-    use std::process::Command;

-    #[tokio::test]
-    async fn test_current_shell_detects_zsh() {
-        let shell = Command::new("sh")
-            .arg("-c")
-            .arg("echo $SHELL")
-            .output()
-            .unwrap();
-
-        let home = std::env::var("HOME").unwrap();
-        let shell_path = String::from_utf8_lossy(&shell.stdout).trim().to_string();
-        if shell_path.ends_with("/zsh") {
-            assert_eq!(
-                default_user_shell().await,
-                Shell::Zsh(ZshShell {
-                    shell_path: shell_path.to_string(),
-                    zshrc_path: format!("{home}/.zshrc",),
-                })
-            );
-        }
-    }
+    use std::path::PathBuf;

    #[tokio::test]
    async fn test_run_with_profile_zshrc_not_exists() {
-        let shell = Shell::Zsh(ZshShell {
+        let shell = Shell::Posix(PosixShell {
            shell_path: "/bin/zsh".to_string(),
-            zshrc_path: "/does/not/exist/.zshrc".to_string(),
+            rc_path: "/does/not/exist/.zshrc".to_string(),
+            shell_snapshot: None,
        });
        let actual_cmd = shell.format_default_shell_invocation(vec!["myecho".to_string()]);
        assert_eq!(
@@ -254,24 +404,7 @@ mod tests {
            Some(vec![
                "/bin/zsh".to_string(),
                "-lc".to_string(),
-                "myecho".to_string()
-            ])
-        );
-    }
-
-    #[tokio::test]
-    async fn test_run_with_profile_bashrc_not_exists() {
-        let shell = Shell::Bash(BashShell {
-            shell_path: "/bin/bash".to_string(),
-            bashrc_path: "/does/not/exist/.bashrc".to_string(),
-        });
-        let actual_cmd = shell.format_default_shell_invocation(vec!["myecho".to_string()]);
-        assert_eq!(
-            actual_cmd,
-            Some(vec![
-                "/bin/bash".to_string(),
-                "-lc".to_string(),
-                "myecho".to_string()
+                "[ -f /does/not/exist/.zshrc ] && . /does/not/exist/.zshrc; (myecho)".to_string(),
            ])
        );
    }
@@ -283,7 +416,11 @@ mod tests {
        let cases = vec![
            (
                vec!["myecho"],
-                vec![shell_path, "-lc", "source BASHRC_PATH && (myecho)"],
+                vec![
+                    shell_path,
+                    "-lc",
+                    "[ -f BASHRC_PATH ] && . BASHRC_PATH; (myecho)",
+                ],
                Some("It works!\n"),
            ),
            (
@@ -291,7 +428,7 @@ mod tests {
                vec![
                    shell_path,
                    "-lc",
-                    "source BASHRC_PATH && (echo 'single' \"double\")",
+                    "[ -f BASHRC_PATH ] && . BASHRC_PATH; (echo 'single' \"double\")",
                ],
                Some("single double\n"),
            ),
@@ -317,16 +454,20 @@ mod tests {
                    "#,
            )
            .unwrap();
-            let shell = Shell::Bash(BashShell {
+            let shell = Shell::Posix(PosixShell {
                shell_path: shell_path.to_string(),
-                bashrc_path: bashrc_path.to_str().unwrap().to_string(),
+                rc_path: bashrc_path.to_str().unwrap().to_string(),
+                shell_snapshot: None,
            });

            let actual_cmd = shell
                .format_default_shell_invocation(input.iter().map(|s| s.to_string()).collect());
            let expected_cmd = expected_cmd
                .iter()
-                .map(|s| s.replace("BASHRC_PATH", bashrc_path.to_str().unwrap()))
+                .map(|s| {
+                    s.replace("BASHRC_PATH", bashrc_path.to_str().unwrap())
+                        .to_string()
+                })
                .collect();

            assert_eq!(actual_cmd, Some(expected_cmd));
@@ -366,6 +507,82 @@ mod tests {
 #[cfg(target_os = "macos")]
 mod macos_tests {
    use super::*;
+    use crate::shell::snapshots::ensure_posix_snapshot;
+
+    #[tokio::test]
+    async fn test_snapshot_generation_uses_session_id_and_cleanup() {
+        let shell_path = "/bin/zsh";
+
+        let temp_home = tempfile::tempdir().unwrap();
+        let codex_home = tempfile::tempdir().unwrap();
+        std::fs::write(
+            temp_home.path().join(".zshrc"),
+            "export SNAPSHOT_TEST_VAR=1\nalias snapshot_test_alias='echo hi'\n",
+        )
+        .unwrap();
+
+        let session_id = Uuid::new_v4();
+        let snapshot_path = ensure_posix_snapshot(
+            shell_path,
+            ".zshrc",
+            temp_home.path(),
+            codex_home.path(),
+            session_id,
+        )
+        .await
+        .expect("snapshot path");
+
+        let filename = snapshot_path
+            .file_name()
+            .unwrap()
+            .to_string_lossy()
+            .to_string();
+        assert!(filename.contains(&session_id.to_string()));
+        assert!(snapshot_path.exists());
+
+        let snapshot_path_second = ensure_posix_snapshot(
+            shell_path,
+            ".zshrc",
+            temp_home.path(),
+            codex_home.path(),
+            session_id,
+        )
+        .await
+        .expect("snapshot path");
+        assert_eq!(snapshot_path, snapshot_path_second);
+
+        let contents = std::fs::read_to_string(&snapshot_path).unwrap();
+        assert!(contents.contains("alias snapshot_test_alias='echo hi'"));
+        assert!(contents.contains("SNAPSHOT_TEST_VAR=1"));
+
+        delete_shell_snapshot(&snapshot_path);
+        assert!(!snapshot_path.exists());
+    }
+
+    #[test]
+    fn format_default_shell_invocation_prefers_snapshot_when_available() {
+        let temp_dir = tempfile::tempdir().unwrap();
+        let snapshot_path = temp_dir.path().join("snapshot.zsh");
+        std::fs::write(&snapshot_path, "export SNAPSHOT_READY=1").unwrap();
+
+        let shell = Shell::Posix(PosixShell {
+            shell_path: "/bin/zsh".to_string(),
+            rc_path: {
+                let path = temp_dir.path().join(".zshrc");
+                std::fs::write(&path, "# test zshrc").unwrap();
+                path.to_string_lossy().to_string()
+            },
+            shell_snapshot: Some(Arc::new(ShellSnapshot::new(snapshot_path.clone()))),
+        });
+
+        let invocation = shell.format_default_shell_invocation(vec!["echo".to_string()]);
+        let expected_command = vec!["/bin/zsh".to_string(), "-c".to_string(), {
+            let snapshot_path = snapshot_path.to_string_lossy();
+            format!("[ -f {snapshot_path} ] && . {snapshot_path}; (echo)")
+        }];
+
+        assert_eq!(invocation, Some(expected_command));
+    }

    #[tokio::test]
    async fn test_run_with_profile_escaping_and_execution() {
@@ -374,12 +591,20 @@ mod macos_tests {
        let cases = vec![
            (
                vec!["myecho"],
-                vec![shell_path, "-lc", "source ZSHRC_PATH && (myecho)"],
+                vec![
+                    shell_path,
+                    "-lc",
+                    "[ -f ZSHRC_PATH ] && . ZSHRC_PATH; (myecho)",
+                ],
                Some("It works!\n"),
            ),
            (
                vec!["myecho"],
-                vec![shell_path, "-lc", "source ZSHRC_PATH && (myecho)"],
+                vec![
+                    shell_path,
+                    "-lc",
+                    "[ -f ZSHRC_PATH ] && . ZSHRC_PATH; (myecho)",
+                ],
                Some("It works!\n"),
            ),
            (
@@ -387,7 +612,7 @@ mod macos_tests {
                vec![
                    shell_path,
                    "-lc",
-                    "source ZSHRC_PATH && (bash -c \"echo 'single' \\\"double\\\"\")",
+                    "[ -f ZSHRC_PATH ] && . ZSHRC_PATH; (bash -c \"echo 'single' \\\"double\\\"\")",
                ],
                Some("single double\n"),
            ),
@@ -396,7 +621,7 @@ mod macos_tests {
                vec![
                    shell_path,
                    "-lc",
-                    "source ZSHRC_PATH && (echo 'single' \"double\")",
+                    "[ -f ZSHRC_PATH ] && . ZSHRC_PATH; (echo 'single' \"double\")",
                ],
                Some("single double\n"),
            ),
@@ -423,16 +648,20 @@ mod macos_tests {
                    "#,
            )
            .unwrap();
-            let shell = Shell::Zsh(ZshShell {
+            let shell = Shell::Posix(PosixShell {
                shell_path: shell_path.to_string(),
-                zshrc_path: zshrc_path.to_str().unwrap().to_string(),
+                rc_path: zshrc_path.to_str().unwrap().to_string(),
+                shell_snapshot: None,
            });

            let actual_cmd = shell
                .format_default_shell_invocation(input.iter().map(|s| s.to_string()).collect());
            let expected_cmd = expected_cmd
                .iter()
-                .map(|s| s.replace("ZSHRC_PATH", zshrc_path.to_str().unwrap()))
+                .map(|s| {
+                    s.replace("ZSHRC_PATH", zshrc_path.to_str().unwrap())
+                        .to_string()
+                })
                .collect();

            assert_eq!(actual_cmd, Some(expected_cmd));
--- a/codex-rs/core/src/token_data.rs
+++ b/codex-rs/core/src/token_data.rs
@@ -3,6 +3,8 @@ use serde::Deserialize;
 use serde::Serialize;
 use thiserror::Error;

+use codex_protocol::mcp_protocol::AuthMode;
+
 #[derive(Deserialize, Serialize, Clone, Debug, PartialEq, Default)]
 pub struct TokenData {
    /// Flat info parsed from the JWT in auth.json.
@@ -20,6 +22,36 @@ pub struct TokenData {
    pub account_id: Option<String>,
 }

+impl TokenData {
+    /// Returns true if this is a plan that should use the traditional
+    /// "metered" billing via an API key.
+    pub(crate) fn should_use_api_key(
+        &self,
+        preferred_auth_method: AuthMode,
+        is_openai_email: bool,
+    ) -> bool {
+        if preferred_auth_method == AuthMode::ApiKey {
+            return true;
+        }
+        // If the email is an OpenAI email, use AuthMode::ChatGPT unless preferred_auth_method is AuthMode::ApiKey.
+        if is_openai_email {
+            return false;
+        }
+
+        self.id_token
+            .chatgpt_plan_type
+            .as_ref()
+            .is_none_or(|plan| plan.is_plan_that_should_use_api_key())
+    }
+
+    pub fn is_openai_email(&self) -> bool {
+        self.id_token
+            .email
+            .as_deref()
+            .is_some_and(|email| email.trim().to_ascii_lowercase().ends_with("@openai.com"))
+    }
+}
+
 /// Flat subset of useful claims in id_token from auth.json.
 #[derive(Debug, Clone, PartialEq, Eq, Default, Serialize, Deserialize)]
 pub struct IdTokenInfo {
@@ -47,6 +79,28 @@ pub(crate) enum PlanType {
    Unknown(String),
 }

+impl PlanType {
+    fn is_plan_that_should_use_api_key(&self) -> bool {
+        match self {
+            Self::Known(known) => {
+                use KnownPlan::*;
+                !matches!(known, Free | Plus | Pro | Team)
+            }
+            Self::Unknown(_) => {
+                // Unknown plans should use the API key.
+                true
+            }
+        }
+    }
+
+    pub fn as_string(&self) -> String {
+        match self {
+            Self::Known(known) => format!("{known:?}").to_lowercase(),
+            Self::Unknown(s) => s.clone(),
+        }
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(rename_all = "lowercase")]
 pub(crate) enum KnownPlan {
--- a/codex-rs/core/src/truncate.rs
+++ b/codex-rs/core/src/truncate.rs
@@ -1,180 +0,0 @@
-//! Utilities for truncating large chunks of output while preserving a prefix
-//! and suffix on UTF-8 boundaries.
-
-/// Truncate the middle of a UTF-8 string to at most `max_bytes` bytes,
-/// preserving the beginning and the end. Returns the possibly truncated
-/// string and `Some(original_token_count)` (estimated at 4 bytes/token)
-/// if truncation occurred; otherwise returns the original string and `None`.
-pub(crate) fn truncate_middle(s: &str, max_bytes: usize) -> (String, Option<u64>) {
-    if s.len() <= max_bytes {
-        return (s.to_string(), None);
-    }
-
-    let est_tokens = (s.len() as u64).div_ceil(4);
-    if max_bytes == 0 {
-        return (format!("…{est_tokens} tokens truncated…"), Some(est_tokens));
-    }
-
-    fn truncate_on_boundary(input: &str, max_len: usize) -> &str {
-        if input.len() <= max_len {
-            return input;
-        }
-        let mut end = max_len;
-        while end > 0 && !input.is_char_boundary(end) {
-            end -= 1;
-        }
-        &input[..end]
-    }
-
-    fn pick_prefix_end(s: &str, left_budget: usize) -> usize {
-        if let Some(head) = s.get(..left_budget)
-            && let Some(i) = head.rfind('\n')
-        {
-            return i + 1;
-        }
-        truncate_on_boundary(s, left_budget).len()
-    }
-
-    fn pick_suffix_start(s: &str, right_budget: usize) -> usize {
-        let start_tail = s.len().saturating_sub(right_budget);
-        if let Some(tail) = s.get(start_tail..)
-            && let Some(i) = tail.find('\n')
-        {
-            return start_tail + i + 1;
-        }
-
-        let mut idx = start_tail.min(s.len());
-        while idx < s.len() && !s.is_char_boundary(idx) {
-            idx += 1;
-        }
-        idx
-    }
-
-    let mut guess_tokens = est_tokens;
-    for _ in 0..4 {
-        let marker = format!("…{guess_tokens} tokens truncated…");
-        let marker_len = marker.len();
-        let keep_budget = max_bytes.saturating_sub(marker_len);
-        if keep_budget == 0 {
-            return (format!("…{est_tokens} tokens truncated…"), Some(est_tokens));
-        }
-
-        let left_budget = keep_budget / 2;
-        let right_budget = keep_budget - left_budget;
-        let prefix_end = pick_prefix_end(s, left_budget);
-        let mut suffix_start = pick_suffix_start(s, right_budget);
-        if suffix_start < prefix_end {
-            suffix_start = prefix_end;
-        }
-
-        let kept_content_bytes = prefix_end + (s.len() - suffix_start);
-        let truncated_content_bytes = s.len().saturating_sub(kept_content_bytes);
-        let new_tokens = (truncated_content_bytes as u64).div_ceil(4);
-
-        if new_tokens == guess_tokens {
-            let mut out = String::with_capacity(marker_len + kept_content_bytes + 1);
-            out.push_str(&s[..prefix_end]);
-            out.push_str(&marker);
-            out.push('\n');
-            out.push_str(&s[suffix_start..]);
-            return (out, Some(est_tokens));
-        }
-
-        guess_tokens = new_tokens;
-    }
-
-    let marker = format!("…{guess_tokens} tokens truncated…");
-    let marker_len = marker.len();
-    let keep_budget = max_bytes.saturating_sub(marker_len);
-    if keep_budget == 0 {
-        return (format!("…{est_tokens} tokens truncated…"), Some(est_tokens));
-    }
-
-    let left_budget = keep_budget / 2;
-    let right_budget = keep_budget - left_budget;
-    let prefix_end = pick_prefix_end(s, left_budget);
-    let suffix_start = pick_suffix_start(s, right_budget);
-
-    let mut out = String::with_capacity(marker_len + prefix_end + (s.len() - suffix_start) + 1);
-    out.push_str(&s[..prefix_end]);
-    out.push_str(&marker);
-    out.push('\n');
-    out.push_str(&s[suffix_start..]);
-    (out, Some(est_tokens))
-}
-
-#[cfg(test)]
-mod tests {
-    use super::truncate_middle;
-
-    #[test]
-    fn truncate_middle_no_newlines_fallback() {
-        let s = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*";
-        let max_bytes = 32;
-        let (out, original) = truncate_middle(s, max_bytes);
-        assert!(out.starts_with("abc"));
-        assert!(out.contains("tokens truncated"));
-        assert!(out.ends_with("XYZ*"));
-        assert_eq!(original, Some((s.len() as u64).div_ceil(4)));
-    }
-
-    #[test]
-    fn truncate_middle_prefers_newline_boundaries() {
-        let mut s = String::new();
-        for i in 1..=20 {
-            s.push_str(&format!("{i:03}\n"));
-        }
-        assert_eq!(s.len(), 80);
-
-        let max_bytes = 64;
-        let (out, tokens) = truncate_middle(&s, max_bytes);
-        assert!(out.starts_with("001\n002\n003\n004\n"));
-        assert!(out.contains("tokens truncated"));
-        assert!(out.ends_with("017\n018\n019\n020\n"));
-        assert_eq!(tokens, Some(20));
-    }
-
-    #[test]
-    fn truncate_middle_handles_utf8_content() {
-        let s = "😀😀😀😀😀😀😀😀😀😀\nsecond line with ascii text\n";
-        let max_bytes = 32;
-        let (out, tokens) = truncate_middle(s, max_bytes);
-
-        assert!(out.contains("tokens truncated"));
-        assert!(!out.contains('\u{fffd}'));
-        assert_eq!(tokens, Some((s.len() as u64).div_ceil(4)));
-    }
-
-    #[test]
-    fn truncate_middle_prefers_newline_boundaries_2() {
-        // Build a multi-line string of 20 numbered lines (each "NNN\n").
-        let mut s = String::new();
-        for i in 1..=20 {
-            s.push_str(&format!("{i:03}\n"));
-        }
-        // Total length: 20 lines * 4 bytes per line = 80 bytes.
-        assert_eq!(s.len(), 80);
-
-        // Choose a cap that forces truncation while leaving room for
-        // a few lines on each side after accounting for the marker.
-        let max_bytes = 64;
-        // Expect exact output: first 4 lines, marker, last 4 lines, and correct token estimate (80/4 = 20).
-        assert_eq!(
-            truncate_middle(&s, max_bytes),
-            (
-                r#"001
-002
-003
-004
-…12 tokens truncated…
-017
-018
-019
-020
-"#
-                .to_string(),
-                Some(20)
-            )
-        );
-    }
-}
--- a/codex-rs/core/src/turn_diff_tracker.rs
+++ b/codex-rs/core/src/turn_diff_tracker.rs
@@ -678,7 +678,7 @@ index {left_oid}..{right_oid}
        let dest = dir.path().join("dest.txt");
        let mut acc = TurnDiffTracker::new();
        let mv = HashMap::from([(
-            src,
+            src.clone(),
            FileChange::Update {
                unified_diff: "".into(),
                move_path: Some(dest.clone()),
--- a/codex-rs/core/src/unified_exec/errors.rs
+++ b/codex-rs/core/src/unified_exec/errors.rs
@@ -1,22 +0,0 @@
-use thiserror::Error;
-
-#[derive(Debug, Error)]
-pub(crate) enum UnifiedExecError {
-    #[error("Failed to create unified exec session: {pty_error}")]
-    CreateSession {
-        #[source]
-        pty_error: anyhow::Error,
-    },
-    #[error("Unknown session id {session_id}")]
-    UnknownSessionId { session_id: i32 },
-    #[error("failed to write to stdin")]
-    WriteToStdin,
-    #[error("missing command line for unified exec request")]
-    MissingCommandLine,
-}
-
-impl UnifiedExecError {
-    pub(crate) fn create_session(error: anyhow::Error) -> Self {
-        Self::CreateSession { pty_error: error }
-    }
-}
--- a/codex-rs/core/src/unified_exec/mod.rs
+++ b/codex-rs/core/src/unified_exec/mod.rs
@@ -1,633 +0,0 @@
-use portable_pty::CommandBuilder;
-use portable_pty::PtySize;
-use portable_pty::native_pty_system;
-use std::collections::HashMap;
-use std::collections::VecDeque;
-use std::io::ErrorKind;
-use std::io::Read;
-use std::sync::Arc;
-use std::sync::Mutex as StdMutex;
-use std::sync::atomic::AtomicBool;
-use std::sync::atomic::AtomicI32;
-use std::sync::atomic::Ordering;
-use tokio::sync::Mutex;
-use tokio::sync::Notify;
-use tokio::sync::mpsc;
-use tokio::task::JoinHandle;
-use tokio::time::Duration;
-use tokio::time::Instant;
-
-use crate::exec_command::ExecCommandSession;
-use crate::truncate::truncate_middle;
-
-mod errors;
-
-pub(crate) use errors::UnifiedExecError;
-
-const DEFAULT_TIMEOUT_MS: u64 = 1_000;
-const MAX_TIMEOUT_MS: u64 = 60_000;
-const UNIFIED_EXEC_OUTPUT_MAX_BYTES: usize = 128 * 1024; // 128 KiB
-
-#[derive(Debug)]
-pub(crate) struct UnifiedExecRequest<'a> {
-    pub session_id: Option<i32>,
-    pub input_chunks: &'a [String],
-    pub timeout_ms: Option<u64>,
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub(crate) struct UnifiedExecResult {
-    pub session_id: Option<i32>,
-    pub output: String,
-}
-
-#[derive(Debug, Default)]
-pub(crate) struct UnifiedExecSessionManager {
-    next_session_id: AtomicI32,
-    sessions: Mutex<HashMap<i32, ManagedUnifiedExecSession>>,
-}
-
-#[derive(Debug)]
-struct ManagedUnifiedExecSession {
-    session: ExecCommandSession,
-    output_buffer: OutputBuffer,
-    /// Notifies waiters whenever new output has been appended to
-    /// `output_buffer`, allowing clients to poll for fresh data.
-    output_notify: Arc<Notify>,
-    output_task: JoinHandle<()>,
-}
-
-#[derive(Debug, Default)]
-struct OutputBufferState {
-    chunks: VecDeque<Vec<u8>>,
-    total_bytes: usize,
-}
-
-impl OutputBufferState {
-    fn push_chunk(&mut self, chunk: Vec<u8>) {
-        self.total_bytes = self.total_bytes.saturating_add(chunk.len());
-        self.chunks.push_back(chunk);
-
-        let mut excess = self
-            .total_bytes
-            .saturating_sub(UNIFIED_EXEC_OUTPUT_MAX_BYTES);
-
-        while excess > 0 {
-            match self.chunks.front_mut() {
-                Some(front) if excess >= front.len() => {
-                    excess -= front.len();
-                    self.total_bytes = self.total_bytes.saturating_sub(front.len());
-                    self.chunks.pop_front();
-                }
-                Some(front) => {
-                    front.drain(..excess);
-                    self.total_bytes = self.total_bytes.saturating_sub(excess);
-                    break;
-                }
-                None => break,
-            }
-        }
-    }
-
-    fn drain(&mut self) -> Vec<Vec<u8>> {
-        let drained: Vec<Vec<u8>> = self.chunks.drain(..).collect();
-        self.total_bytes = 0;
-        drained
-    }
-}
-
-type OutputBuffer = Arc<Mutex<OutputBufferState>>;
-type OutputHandles = (OutputBuffer, Arc<Notify>);
-
-impl ManagedUnifiedExecSession {
-    fn new(session: ExecCommandSession) -> Self {
-        let output_buffer = Arc::new(Mutex::new(OutputBufferState::default()));
-        let output_notify = Arc::new(Notify::new());
-        let mut receiver = session.output_receiver();
-        let buffer_clone = Arc::clone(&output_buffer);
-        let notify_clone = Arc::clone(&output_notify);
-        let output_task = tokio::spawn(async move {
-            while let Ok(chunk) = receiver.recv().await {
-                let mut guard = buffer_clone.lock().await;
-                guard.push_chunk(chunk);
-                drop(guard);
-                notify_clone.notify_waiters();
-            }
-        });
-
-        Self {
-            session,
-            output_buffer,
-            output_notify,
-            output_task,
-        }
-    }
-
-    fn writer_sender(&self) -> mpsc::Sender<Vec<u8>> {
-        self.session.writer_sender()
-    }
-
-    fn output_handles(&self) -> OutputHandles {
-        (
-            Arc::clone(&self.output_buffer),
-            Arc::clone(&self.output_notify),
-        )
-    }
-
-    fn has_exited(&self) -> bool {
-        self.session.has_exited()
-    }
-}
-
-impl Drop for ManagedUnifiedExecSession {
-    fn drop(&mut self) {
-        self.output_task.abort();
-    }
-}
-
-impl UnifiedExecSessionManager {
-    pub async fn handle_request(
-        &self,
-        request: UnifiedExecRequest<'_>,
-    ) -> Result<UnifiedExecResult, UnifiedExecError> {
-        let (timeout_ms, timeout_warning) = match request.timeout_ms {
-            Some(requested) if requested > MAX_TIMEOUT_MS => (
-                MAX_TIMEOUT_MS,
-                Some(format!(
-                    "Warning: requested timeout {requested}ms exceeds maximum of {MAX_TIMEOUT_MS}ms; clamping to {MAX_TIMEOUT_MS}ms.\n"
-                )),
-            ),
-            Some(requested) => (requested, None),
-            None => (DEFAULT_TIMEOUT_MS, None),
-        };
-
-        let mut new_session: Option<ManagedUnifiedExecSession> = None;
-        let session_id;
-        let writer_tx;
-        let output_buffer;
-        let output_notify;
-
-        if let Some(existing_id) = request.session_id {
-            let mut sessions = self.sessions.lock().await;
-            match sessions.get(&existing_id) {
-                Some(session) => {
-                    if session.has_exited() {
-                        sessions.remove(&existing_id);
-                        return Err(UnifiedExecError::UnknownSessionId {
-                            session_id: existing_id,
-                        });
-                    }
-                    let (buffer, notify) = session.output_handles();
-                    session_id = existing_id;
-                    writer_tx = session.writer_sender();
-                    output_buffer = buffer;
-                    output_notify = notify;
-                }
-                None => {
-                    return Err(UnifiedExecError::UnknownSessionId {
-                        session_id: existing_id,
-                    });
-                }
-            }
-            drop(sessions);
-        } else {
-            let command = request.input_chunks.to_vec();
-            let new_id = self.next_session_id.fetch_add(1, Ordering::SeqCst);
-            let session = create_unified_exec_session(&command).await?;
-            let managed_session = ManagedUnifiedExecSession::new(session);
-            let (buffer, notify) = managed_session.output_handles();
-            writer_tx = managed_session.writer_sender();
-            output_buffer = buffer;
-            output_notify = notify;
-            session_id = new_id;
-            new_session = Some(managed_session);
-        };
-
-        if request.session_id.is_some() {
-            let joined_input = request.input_chunks.join(" ");
-            if !joined_input.is_empty() && writer_tx.send(joined_input.into_bytes()).await.is_err()
-            {
-                return Err(UnifiedExecError::WriteToStdin);
-            }
-        }
-
-        let mut collected: Vec<u8> = Vec::with_capacity(4096);
-        let start = Instant::now();
-        let deadline = start + Duration::from_millis(timeout_ms);
-
-        loop {
-            let drained_chunks;
-            let mut wait_for_output = None;
-            {
-                let mut guard = output_buffer.lock().await;
-                drained_chunks = guard.drain();
-                if drained_chunks.is_empty() {
-                    wait_for_output = Some(output_notify.notified());
-                }
-            }
-
-            if drained_chunks.is_empty() {
-                let remaining = deadline.saturating_duration_since(Instant::now());
-                if remaining == Duration::ZERO {
-                    break;
-                }
-
-                let notified = wait_for_output.unwrap_or_else(|| output_notify.notified());
-                tokio::pin!(notified);
-                tokio::select! {
-                    _ = &mut notified => {}
-                    _ = tokio::time::sleep(remaining) => break,
-                }
-                continue;
-            }
-
-            for chunk in drained_chunks {
-                collected.extend_from_slice(&chunk);
-            }
-
-            if Instant::now() >= deadline {
-                break;
-            }
-        }
-
-        let (output, _maybe_tokens) = truncate_middle(
-            &String::from_utf8_lossy(&collected),
-            UNIFIED_EXEC_OUTPUT_MAX_BYTES,
-        );
-        let output = if let Some(warning) = timeout_warning {
-            format!("{warning}{output}")
-        } else {
-            output
-        };
-
-        let should_store_session = if let Some(session) = new_session.as_ref() {
-            !session.has_exited()
-        } else if request.session_id.is_some() {
-            let mut sessions = self.sessions.lock().await;
-            if let Some(existing) = sessions.get(&session_id) {
-                if existing.has_exited() {
-                    sessions.remove(&session_id);
-                    false
-                } else {
-                    true
-                }
-            } else {
-                false
-            }
-        } else {
-            true
-        };
-
-        if should_store_session {
-            if let Some(session) = new_session {
-                self.sessions.lock().await.insert(session_id, session);
-            }
-            Ok(UnifiedExecResult {
-                session_id: Some(session_id),
-                output,
-            })
-        } else {
-            Ok(UnifiedExecResult {
-                session_id: None,
-                output,
-            })
-        }
-    }
-}
-
-async fn create_unified_exec_session(
-    command: &[String],
-) -> Result<ExecCommandSession, UnifiedExecError> {
-    if command.is_empty() {
-        return Err(UnifiedExecError::MissingCommandLine);
-    }
-
-    let pty_system = native_pty_system();
-
-    let pair = pty_system
-        .openpty(PtySize {
-            rows: 24,
-            cols: 80,
-            pixel_width: 0,
-            pixel_height: 0,
-        })
-        .map_err(UnifiedExecError::create_session)?;
-
-    // Safe thanks to the check at the top of the function.
-    let mut command_builder = CommandBuilder::new(command[0].clone());
-    for arg in &command[1..] {
-        command_builder.arg(arg);
-    }
-
-    let mut child = pair
-        .slave
-        .spawn_command(command_builder)
-        .map_err(UnifiedExecError::create_session)?;
-    let killer = child.clone_killer();
-
-    let (writer_tx, mut writer_rx) = mpsc::channel::<Vec<u8>>(128);
-    let (output_tx, _) = tokio::sync::broadcast::channel::<Vec<u8>>(256);
-
-    let mut reader = pair
-        .master
-        .try_clone_reader()
-        .map_err(UnifiedExecError::create_session)?;
-    let output_tx_clone = output_tx.clone();
-    let reader_handle = tokio::task::spawn_blocking(move || {
-        let mut buf = [0u8; 8192];
-        loop {
-            match reader.read(&mut buf) {
-                Ok(0) => break,
-                Ok(n) => {
-                    let _ = output_tx_clone.send(buf[..n].to_vec());
-                }
-                Err(ref e) if e.kind() == ErrorKind::Interrupted => continue,
-                Err(ref e) if e.kind() == ErrorKind::WouldBlock => {
-                    std::thread::sleep(Duration::from_millis(5));
-                    continue;
-                }
-                Err(_) => break,
-            }
-        }
-    });
-
-    let writer = pair
-        .master
-        .take_writer()
-        .map_err(UnifiedExecError::create_session)?;
-    let writer = Arc::new(StdMutex::new(writer));
-    let writer_handle = tokio::spawn({
-        let writer = writer.clone();
-        async move {
-            while let Some(bytes) = writer_rx.recv().await {
-                let writer = writer.clone();
-                let _ = tokio::task::spawn_blocking(move || {
-                    if let Ok(mut guard) = writer.lock() {
-                        use std::io::Write;
-                        let _ = guard.write_all(&bytes);
-                        let _ = guard.flush();
-                    }
-                })
-                .await;
-            }
-        }
-    });
-
-    let exit_status = Arc::new(AtomicBool::new(false));
-    let wait_exit_status = Arc::clone(&exit_status);
-    let wait_handle = tokio::task::spawn_blocking(move || {
-        let _ = child.wait();
-        wait_exit_status.store(true, Ordering::SeqCst);
-    });
-
-    Ok(ExecCommandSession::new(
-        writer_tx,
-        output_tx,
-        killer,
-        reader_handle,
-        writer_handle,
-        wait_handle,
-        exit_status,
-    ))
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn push_chunk_trims_only_excess_bytes() {
-        let mut buffer = OutputBufferState::default();
-        buffer.push_chunk(vec![b'a'; UNIFIED_EXEC_OUTPUT_MAX_BYTES]);
-        buffer.push_chunk(vec![b'b']);
-        buffer.push_chunk(vec![b'c']);
-
-        assert_eq!(buffer.total_bytes, UNIFIED_EXEC_OUTPUT_MAX_BYTES);
-        assert_eq!(buffer.chunks.len(), 3);
-        assert_eq!(
-            buffer.chunks.front().unwrap().len(),
-            UNIFIED_EXEC_OUTPUT_MAX_BYTES - 2
-        );
-        assert_eq!(buffer.chunks.pop_back().unwrap(), vec![b'c']);
-        assert_eq!(buffer.chunks.pop_back().unwrap(), vec![b'b']);
-    }
-
-    #[cfg(unix)]
-    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-    async fn unified_exec_persists_across_requests_jif() -> Result<(), UnifiedExecError> {
-        let manager = UnifiedExecSessionManager::default();
-
-        let open_shell = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: None,
-                input_chunks: &["bash".to_string(), "-i".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-        let session_id = open_shell.session_id.expect("expected session_id");
-
-        manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_id),
-                input_chunks: &[
-                    "export".to_string(),
-                    "CODEX_INTERACTIVE_SHELL_VAR=codex\n".to_string(),
-                ],
-                timeout_ms: Some(2_500),
-            })
-            .await?;
-
-        let out_2 = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_id),
-                input_chunks: &["echo $CODEX_INTERACTIVE_SHELL_VAR\n".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-        assert!(out_2.output.contains("codex"));
-
-        Ok(())
-    }
-
-    #[cfg(unix)]
-    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-    async fn multi_unified_exec_sessions() -> Result<(), UnifiedExecError> {
-        let manager = UnifiedExecSessionManager::default();
-
-        let shell_a = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: None,
-                input_chunks: &["/bin/bash".to_string(), "-i".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-        let session_a = shell_a.session_id.expect("expected session id");
-
-        manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_a),
-                input_chunks: &["export CODEX_INTERACTIVE_SHELL_VAR=codex\n".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-
-        let out_2 = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: None,
-                input_chunks: &[
-                    "echo".to_string(),
-                    "$CODEX_INTERACTIVE_SHELL_VAR\n".to_string(),
-                ],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-        assert!(!out_2.output.contains("codex"));
-
-        let out_3 = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_a),
-                input_chunks: &["echo $CODEX_INTERACTIVE_SHELL_VAR\n".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-        assert!(out_3.output.contains("codex"));
-
-        Ok(())
-    }
-
-    #[cfg(unix)]
-    #[tokio::test]
-    async fn unified_exec_timeouts() -> Result<(), UnifiedExecError> {
-        let manager = UnifiedExecSessionManager::default();
-
-        let open_shell = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: None,
-                input_chunks: &["bash".to_string(), "-i".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-        let session_id = open_shell.session_id.expect("expected session id");
-
-        manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_id),
-                input_chunks: &[
-                    "export".to_string(),
-                    "CODEX_INTERACTIVE_SHELL_VAR=codex\n".to_string(),
-                ],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-
-        let out_2 = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_id),
-                input_chunks: &["sleep 5 && echo $CODEX_INTERACTIVE_SHELL_VAR\n".to_string()],
-                timeout_ms: Some(10),
-            })
-            .await?;
-        assert!(!out_2.output.contains("codex"));
-
-        tokio::time::sleep(Duration::from_secs(7)).await;
-
-        let empty = Vec::new();
-        let out_3 = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_id),
-                input_chunks: &empty,
-                timeout_ms: Some(100),
-            })
-            .await?;
-
-        assert!(out_3.output.contains("codex"));
-
-        Ok(())
-    }
-
-    #[cfg(unix)]
-    #[tokio::test]
-    async fn requests_with_large_timeout_are_capped() -> Result<(), UnifiedExecError> {
-        let manager = UnifiedExecSessionManager::default();
-
-        let result = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: None,
-                input_chunks: &["echo".to_string(), "codex".to_string()],
-                timeout_ms: Some(120_000),
-            })
-            .await?;
-
-        assert!(result.output.starts_with(
-            "Warning: requested timeout 120000ms exceeds maximum of 60000ms; clamping to 60000ms.\n"
-        ));
-        assert!(result.output.contains("codex"));
-
-        Ok(())
-    }
-
-    #[cfg(unix)]
-    #[tokio::test]
-    async fn completed_commands_do_not_persist_sessions() -> Result<(), UnifiedExecError> {
-        let manager = UnifiedExecSessionManager::default();
-        let result = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: None,
-                input_chunks: &["/bin/echo".to_string(), "codex".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-
-        assert!(result.session_id.is_none());
-        assert!(result.output.contains("codex"));
-
-        assert!(manager.sessions.lock().await.is_empty());
-
-        Ok(())
-    }
-
-    #[cfg(unix)]
-    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-    async fn reusing_completed_session_returns_unknown_session() -> Result<(), UnifiedExecError> {
-        let manager = UnifiedExecSessionManager::default();
-
-        let open_shell = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: None,
-                input_chunks: &["/bin/bash".to_string(), "-i".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-        let session_id = open_shell.session_id.expect("expected session id");
-
-        manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_id),
-                input_chunks: &["exit\n".to_string()],
-                timeout_ms: Some(1_500),
-            })
-            .await?;
-
-        tokio::time::sleep(Duration::from_millis(200)).await;
-
-        let err = manager
-            .handle_request(UnifiedExecRequest {
-                session_id: Some(session_id),
-                input_chunks: &[],
-                timeout_ms: Some(100),
-            })
-            .await
-            .expect_err("expected unknown session error");
-
-        match err {
-            UnifiedExecError::UnknownSessionId { session_id: err_id } => {
-                assert_eq!(err_id, session_id);
-            }
-            other => panic!("expected UnknownSessionId, got {other:?}"),
-        }
-
-        assert!(!manager.sessions.lock().await.contains_key(&session_id));
-
-        Ok(())
-    }
-}
--- a/codex-rs/core/tests/suite/cli_stream.rs
+++ b/codex-rs/core/tests/suite/cli_stream.rs
@@ -1,6 +1,4 @@
 use assert_cmd::Command as AssertCommand;
-use codex_core::RolloutRecorder;
-use codex_core::protocol::GitInfo;
 use codex_core::spawn::CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR;
 use std::time::Duration;
 use std::time::Instant;
@@ -79,22 +77,6 @@ async fn chat_mode_stream_cli() {
    assert_eq!(hi_lines, 1, "Expected exactly one line with 'hi'");

    server.verify().await;
-
-    // Verify a new session rollout was created and is discoverable via list_conversations
-    let page = RolloutRecorder::list_conversations(home.path(), 10, None)
-        .await
-        .expect("list conversations");
-    assert!(
-        !page.items.is_empty(),
-        "expected at least one session to be listed"
-    );
-    // First line of head must be the SessionMeta payload (id/timestamp)
-    let head0 = page.items[0].head.first().expect("missing head record");
-    assert!(head0.get("id").is_some(), "head[0] missing id");
-    assert!(
-        head0.get("timestamp").is_some(),
-        "head[0] missing timestamp"
-    );
 }

 /// Verify that passing `-c experimental_instructions_file=...` to the CLI
@@ -315,10 +297,8 @@ async fn integration_creates_and_checks_session_file() {
                    Ok(v) => v,
                    Err(_) => continue,
                };
-                if item.get("type").and_then(|t| t.as_str()) == Some("response_item")
-                    && let Some(payload) = item.get("payload")
-                    && payload.get("type").and_then(|t| t.as_str()) == Some("message")
-                    && let Some(c) = payload.get("content")
+                if item.get("type").and_then(|t| t.as_str()) == Some("message")
+                    && let Some(c) = item.get("content")
                    && c.to_string().contains(&marker)
                {
                    matching_path = Some(path.to_path_buf());
@@ -381,16 +361,9 @@ async fn integration_creates_and_checks_session_file() {
        .unwrap_or_else(|_| panic!("missing session meta line"));
    let meta: serde_json::Value = serde_json::from_str(meta_line)
        .unwrap_or_else(|_| panic!("Failed to parse session meta line as JSON"));
-    assert_eq!(
-        meta.get("type").and_then(|v| v.as_str()),
-        Some("session_meta")
-    );
-    let payload = meta
-        .get("payload")
-        .unwrap_or_else(|| panic!("Missing payload in meta line"));
-    assert!(payload.get("id").is_some(), "SessionMeta missing id");
+    assert!(meta.get("id").is_some(), "SessionMeta missing id");
    assert!(
-        payload.get("timestamp").is_some(),
+        meta.get("timestamp").is_some(),
        "SessionMeta missing timestamp"
    );

@@ -402,10 +375,8 @@ async fn integration_creates_and_checks_session_file() {
        let Ok(item) = serde_json::from_str::<serde_json::Value>(line) else {
            continue;
        };
-        if item.get("type").and_then(|t| t.as_str()) == Some("response_item")
-            && let Some(payload) = item.get("payload")
-            && payload.get("type").and_then(|t| t.as_str()) == Some("message")
-            && let Some(c) = payload.get("content")
+        if item.get("type").and_then(|t| t.as_str()) == Some("message")
+            && let Some(c) = item.get("content")
            && c.to_string().contains(&marker)
        {
            found_message = true;
@@ -618,7 +589,7 @@ async fn integration_git_info_unit_test() {

    // 5. Test serialization to ensure it works in SessionMeta
    let serialized = serde_json::to_string(&git_info).unwrap();
-    let deserialized: GitInfo = serde_json::from_str(&serialized).unwrap();
+    let deserialized: codex_core::git_info::GitInfo = serde_json::from_str(&serialized).unwrap();

    assert_eq!(git_info.commit_hash, deserialized.commit_hash);
    assert_eq!(git_info.branch, deserialized.branch);
--- a/codex-rs/core/tests/suite/client.rs
+++ b/codex-rs/core/tests/suite/client.rs
@@ -4,12 +4,11 @@ use codex_core::ModelProviderInfo;
 use codex_core::NewConversation;
 use codex_core::WireApi;
 use codex_core::built_in_model_providers;
-use codex_core::project_doc::get_user_instructions;
 use codex_core::protocol::EventMsg;
 use codex_core::protocol::InputItem;
 use codex_core::protocol::Op;
-use codex_core::shell::default_user_shell;
 use codex_core::spawn::CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR;
+use codex_protocol::mcp_protocol::AuthMode;
 use core_test_support::load_default_config_for_test;
 use core_test_support::load_sse_fixture_with_id;
 use core_test_support::wait_for_event;
@@ -124,22 +123,10 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
    let tmpdir = TempDir::new().unwrap();
    let session_path = tmpdir.path().join("resume-session.jsonl");
    let mut f = std::fs::File::create(&session_path).unwrap();
-    let convo_id = Uuid::new_v4();
    writeln!(
        f,
        "{}",
-        json!({
-            "timestamp": "2024-01-01T00:00:00.000Z",
-            "type": "session_meta",
-            "payload": {
-                "id": convo_id,
-                "timestamp": "2024-01-01T00:00:00Z",
-                "instructions": "be nice",
-                "cwd": ".",
-                "originator": "test_originator",
-                "cli_version": "test_version"
-            }
-        })
+        json!({"meta":"test","instructions":"be nice", "id": Uuid::new_v4(), "timestamp": "2024-01-01T00:00:00Z"})
    )
    .unwrap();

@@ -151,17 +138,7 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
            text: "resumed user message".to_string(),
        }],
    };
-    let prior_user_json = serde_json::to_value(&prior_user).unwrap();
-    writeln!(
-        f,
-        "{}",
-        json!({
-            "timestamp": "2024-01-01T00:00:01.000Z",
-            "type": "response_item",
-            "payload": prior_user_json
-        })
-    )
-    .unwrap();
+    writeln!(f, "{}", serde_json::to_string(&prior_user).unwrap()).unwrap();

    // Prior item: system message (excluded from API history)
    let prior_system = codex_protocol::models::ResponseItem::Message {
@@ -171,17 +148,7 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
            text: "resumed system instruction".to_string(),
        }],
    };
-    let prior_system_json = serde_json::to_value(&prior_system).unwrap();
-    writeln!(
-        f,
-        "{}",
-        json!({
-            "timestamp": "2024-01-01T00:00:02.000Z",
-            "type": "response_item",
-            "payload": prior_system_json
-        })
-    )
-    .unwrap();
+    writeln!(f, "{}", serde_json::to_string(&prior_system).unwrap()).unwrap();

    // Prior item: assistant message
    let prior_item = codex_protocol::models::ResponseItem::Message {
@@ -191,17 +158,7 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
            text: "resumed assistant message".to_string(),
        }],
    };
-    let prior_item_json = serde_json::to_value(&prior_item).unwrap();
-    writeln!(
-        f,
-        "{}",
-        json!({
-            "timestamp": "2024-01-01T00:00:03.000Z",
-            "type": "response_item",
-            "payload": prior_item_json
-        })
-    )
-    .unwrap();
+    writeln!(f, "{}", serde_json::to_string(&prior_item).unwrap()).unwrap();
    drop(f);

    // Mock server that will receive the resumed request
@@ -223,8 +180,6 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
    };
    let codex_home = TempDir::new().unwrap();
    let mut config = load_default_config_for_test(&codex_home);
-    let cwd = TempDir::new().unwrap();
-    config.cwd = cwd.path().to_path_buf();
    config.model_provider = model_provider;
    config.experimental_resume = Some(session_path.clone());
    // Also configure user instructions to ensure they are NOT delivered on resume.
@@ -241,13 +196,16 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
        .await
        .expect("create new conversation");

-    // 1) Assert initial_messages only includes existing EventMsg entries; response items are not converted
+    // 1) Assert initial_messages contains the prior user + assistant messages as EventMsg entries
    let initial_msgs = session_configured
        .initial_messages
        .clone()
-        .expect("expected initial messages option for resumed session");
+        .expect("expected initial messages for resumed session");
    let initial_json = serde_json::to_value(&initial_msgs).unwrap();
-    let expected_initial_json = json!([]);
+    let expected_initial_json = json!([
+        { "type": "user_message", "message": "resumed user message", "kind": "plain" },
+        { "type": "agent_message", "message": "resumed assistant message" }
+    ]);
    assert_eq!(initial_json, expected_initial_json);

    // 2) Submit new input; the request body must include the prior item followed by the new user input.
@@ -263,29 +221,6 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {

    let request = &server.received_requests().await.unwrap()[0];
    let request_body = request.body_json::<serde_json::Value>().unwrap();
-
-    // Build expected environment context for this turn.
-    let shell = default_user_shell().await;
-    let shell_line = match shell.name() {
-        Some(name) => format!("  <shell>{name}</shell>\n"),
-        None => String::new(),
-    };
-    let expected_env_text_turn = format!(
-        r#"<environment_context>
-  <cwd>{}</cwd>
-  <approval_policy>on-request</approval_policy>
-  <sandbox_mode>read-only</sandbox_mode>
-  <network_access>restricted</network_access>
-{}</environment_context>"#,
-        cwd.path().to_string_lossy(),
-        shell_line.as_str(),
-    );
-    let expected_env_msg_turn = json!({
-        "type": "message",
-        "role": "user",
-        "content": [ { "type": "input_text", "text": expected_env_text_turn } ]
-    });
-
    let expected_input = json!([
        {
            "type": "message",
@@ -297,14 +232,12 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
            "role": "assistant",
            "content": [{ "type": "output_text", "text": "resumed assistant message" }]
        },
-        expected_env_msg_turn,
        {
            "type": "message",
            "role": "user",
            "content": [{ "type": "input_text", "text": "hello" }]
        }
    ]);
-
    assert_eq!(request_body["input"], expected_input);
 }

@@ -438,6 +371,56 @@ async fn includes_base_instructions_override_in_request() {
    );
 }

+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn originator_config_override_is_used() {
+    // Mock server
+    let server = MockServer::start().await;
+
+    let first = ResponseTemplate::new(200)
+        .insert_header("content-type", "text/event-stream")
+        .set_body_raw(sse_completed("resp1"), "text/event-stream");
+
+    Mock::given(method("POST"))
+        .and(path("/v1/responses"))
+        .respond_with(first)
+        .expect(1)
+        .mount(&server)
+        .await;
+
+    let model_provider = ModelProviderInfo {
+        base_url: Some(format!("{}/v1", server.uri())),
+        ..built_in_model_providers()["openai"].clone()
+    };
+
+    let codex_home = TempDir::new().unwrap();
+    let mut config = load_default_config_for_test(&codex_home);
+    config.model_provider = model_provider;
+    config.responses_originator_header = "my_override".to_owned();
+
+    let conversation_manager =
+        ConversationManager::with_auth(CodexAuth::from_api_key("Test API Key"));
+    let codex = conversation_manager
+        .new_conversation(config)
+        .await
+        .expect("create new conversation")
+        .conversation;
+
+    codex
+        .submit(Op::UserInput {
+            items: vec![InputItem::Text {
+                text: "hello".into(),
+            }],
+        })
+        .await
+        .unwrap();
+
+    wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
+
+    let request = &server.received_requests().await.unwrap()[0];
+    let request_originator = request.headers.get("originator").unwrap();
+    assert_eq!(request_originator.to_str().unwrap(), "my_override");
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn chatgpt_auth_sends_correct_request() {
    if std::env::var(CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR).is_ok() {
@@ -517,6 +500,82 @@ async fn chatgpt_auth_sends_correct_request() {
    );
 }

+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn prefers_chatgpt_token_when_config_prefers_chatgpt() {
+    if std::env::var(CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR).is_ok() {
+        println!(
+            "Skipping test because it cannot execute when network is disabled in a Codex sandbox."
+        );
+        return;
+    }
+
+    // Mock server
+    let server = MockServer::start().await;
+
+    let first = ResponseTemplate::new(200)
+        .insert_header("content-type", "text/event-stream")
+        .set_body_raw(sse_completed("resp1"), "text/event-stream");
+
+    // Expect ChatGPT base path and correct headers
+    Mock::given(method("POST"))
+        .and(path("/v1/responses"))
+        .and(header_regex("Authorization", r"Bearer Access-123"))
+        .and(header_regex("chatgpt-account-id", r"acc-123"))
+        .respond_with(first)
+        .expect(1)
+        .mount(&server)
+        .await;
+
+    let model_provider = ModelProviderInfo {
+        base_url: Some(format!("{}/v1", server.uri())),
+        ..built_in_model_providers()["openai"].clone()
+    };
+
+    // Init session
+    let codex_home = TempDir::new().unwrap();
+    // Write auth.json that contains both API key and ChatGPT tokens for a plan that should prefer ChatGPT.
+    let _jwt = write_auth_json(
+        &codex_home,
+        Some("sk-test-key"),
+        "pro",
+        "Access-123",
+        Some("acc-123"),
+    );
+
+    let mut config = load_default_config_for_test(&codex_home);
+    config.model_provider = model_provider;
+    config.preferred_auth_method = AuthMode::ChatGPT;
+
+    let auth_manager = match CodexAuth::from_codex_home(
+        codex_home.path(),
+        config.preferred_auth_method,
+        &config.responses_originator_header,
+    ) {
+        Ok(Some(auth)) => codex_core::AuthManager::from_auth_for_testing(auth),
+        Ok(None) => panic!("No CodexAuth found in codex_home"),
+        Err(e) => panic!("Failed to load CodexAuth: {e}"),
+    };
+    let conversation_manager = ConversationManager::new(auth_manager);
+    let NewConversation {
+        conversation: codex,
+        ..
+    } = conversation_manager
+        .new_conversation(config)
+        .await
+        .expect("create new conversation");
+
+    codex
+        .submit(Op::UserInput {
+            items: vec![InputItem::Text {
+                text: "hello".into(),
+            }],
+        })
+        .await
+        .unwrap();
+
+    wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn prefers_apikey_when_config_prefers_apikey_even_with_chatgpt_tokens() {
    if std::env::var(CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR).is_ok() {
@@ -561,8 +620,13 @@ async fn prefers_apikey_when_config_prefers_apikey_even_with_chatgpt_tokens() {

    let mut config = load_default_config_for_test(&codex_home);
    config.model_provider = model_provider;
+    config.preferred_auth_method = AuthMode::ApiKey;

-    let auth_manager = match CodexAuth::from_codex_home(codex_home.path()) {
+    let auth_manager = match CodexAuth::from_codex_home(
+        codex_home.path(),
+        config.preferred_auth_method,
+        &config.responses_originator_header,
+    ) {
        Ok(Some(auth)) => codex_core::AuthManager::from_auth_for_testing(auth),
        Ok(None) => panic!("No CodexAuth found in codex_home"),
        Err(e) => panic!("Failed to load CodexAuth: {e}"),
@@ -867,7 +931,7 @@ async fn history_dedupes_streamed_and_final_messages_across_turns() {
        conversation: codex,
        ..
    } = conversation_manager
-        .new_conversation(config.clone())
+        .new_conversation(config)
        .await
        .expect("create new conversation");

@@ -902,49 +966,34 @@ async fn history_dedupes_streamed_and_final_messages_across_turns() {
    let requests = server.received_requests().await.unwrap();
    assert_eq!(requests.len(), 3, "expected 3 requests (one per turn)");

-    // Build expected environment context dynamically to avoid OS-dependent flakiness.
-    let user_instructions = get_user_instructions(&config).await;
-    let shell = default_user_shell().await;
-    let shell_line = match shell.name() {
-        Some(name) => format!("  <shell>{name}</shell>\n"),
-        None => String::new(),
-    };
-    let expected_env_text = format!(
-        r#"<environment_context>
-  <cwd>{}</cwd>
-  <approval_policy>on-request</approval_policy>
-  <sandbox_mode>read-only</sandbox_mode>
-  <network_access>restricted</network_access>
-{}</environment_context>"#,
-        std::env::current_dir().unwrap().to_string_lossy(),
-        shell_line.as_str(),
-    );
-    let expected_env_msg = json!({
-        "type": "message",
-        "role": "user",
-        "content": [ { "type": "input_text", "text": expected_env_text } ]
-    });
-    // Wrap user instructions in the XML container to match the raw/ingest view
-    let expected_ui_text = format!(
-        "<user_instructions>\n\n{}\n\n</user_instructions>",
-        user_instructions.clone().unwrap()
-    );
-    let expected_ui_msg = json!({
-        "type": "message",
-        "role": "user",
-        "content": [ { "type": "input_text", "text": expected_ui_text } ]
-    });
-
-    let expected_full = json!([
-        expected_ui_msg,
-        expected_env_msg.clone(),
-        {"type":"message","role":"user","content":[{"type":"input_text","text":"U1"}]},
-        {"type":"message","role":"assistant","content":[{"type":"output_text","text":"Hey there!\n"}]},
-        expected_env_msg.clone(),
-        {"type":"message","role":"user","content":[{"type":"input_text","text":"U2"}]},
-        {"type":"message","role":"assistant","content":[{"type":"output_text","text":"Hey there!\n"}]},
-        expected_env_msg,
-        {"type":"message","role":"user","content":[{"type":"input_text","text":"U3"}]}]);
+    // Replace full-array compare with tail-only raw JSON compare using a single hard-coded value.
+    let r3_tail_expected = json!([
+        {
+            "type": "message",
+            "role": "user",
+            "content": [{"type":"input_text","text":"U1"}]
+        },
+        {
+            "type": "message",
+            "role": "assistant",
+            "content": [{"type":"output_text","text":"Hey there!\n"}]
+        },
+        {
+            "type": "message",
+            "role": "user",
+            "content": [{"type":"input_text","text":"U2"}]
+        },
+        {
+            "type": "message",
+            "role": "assistant",
+            "content": [{"type":"output_text","text":"Hey there!\n"}]
+        },
+        {
+            "type": "message",
+            "role": "user",
+            "content": [{"type":"input_text","text":"U3"}]
+        }
+    ]);

    let r3_input_array = requests[2]
        .body_json::<serde_json::Value>()
@@ -953,6 +1002,12 @@ async fn history_dedupes_streamed_and_final_messages_across_turns() {
        .and_then(|v| v.as_array())
        .cloned()
        .expect("r3 missing input array");
-
-    assert_eq!(json!(r3_input_array), expected_full);
+    // skipping earlier context and developer messages
+    let tail_len = r3_tail_expected.as_array().unwrap().len();
+    let actual_tail = &r3_input_array[r3_input_array.len() - tail_len..];
+    assert_eq!(
+        serde_json::Value::Array(actual_tail.to_vec()),
+        r3_tail_expected,
+        "request 3 tail mismatch",
+    );
 }
--- a/codex-rs/core/tests/suite/compact.rs
+++ b/codex-rs/core/tests/suite/compact.rs
@@ -3,13 +3,10 @@
 use codex_core::CodexAuth;
 use codex_core::ConversationManager;
 use codex_core::ModelProviderInfo;
-use codex_core::NewConversation;
 use codex_core::built_in_model_providers;
 use codex_core::protocol::EventMsg;
 use codex_core::protocol::InputItem;
 use codex_core::protocol::Op;
-use codex_core::protocol::RolloutItem;
-use codex_core::protocol::RolloutLine;
 use codex_core::spawn::CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR;
 use core_test_support::load_default_config_for_test;
 use core_test_support::wait_for_event;
@@ -145,12 +142,11 @@ async fn summarize_context_three_requests_and_instructions() {
    let mut config = load_default_config_for_test(&home);
    config.model_provider = model_provider;
    let conversation_manager = ConversationManager::with_auth(CodexAuth::from_api_key("dummy"));
-    let NewConversation {
-        conversation: codex,
-        session_configured,
-        ..
-    } = conversation_manager.new_conversation(config).await.unwrap();
-    let rollout_path = session_configured.rollout_path;
+    let codex = conversation_manager
+        .new_conversation(config)
+        .await
+        .unwrap()
+        .conversation;

    // 1) Normal user input – should hit server once.
    codex
@@ -252,47 +248,4 @@ async fn summarize_context_three_requests_and_instructions() {
        !messages.iter().any(|(_, t)| t.contains(SUMMARIZE_TRIGGER)),
        "third request should not include the summarize trigger"
    );
-
-    // Shut down Codex to flush rollout entries before inspecting the file.
-    codex.submit(Op::Shutdown).await.unwrap();
-    wait_for_event(&codex, |ev| matches!(ev, EventMsg::ShutdownComplete)).await;
-
-    // Verify rollout contains APITurn entries for each API call and a Compacted entry.
-    let text = std::fs::read_to_string(&rollout_path).unwrap_or_else(|e| {
-        panic!(
-            "failed to read rollout file {}: {e}",
-            rollout_path.display()
-        )
-    });
-    let mut api_turn_count = 0usize;
-    let mut saw_compacted_summary = false;
-    for line in text.lines() {
-        let trimmed = line.trim();
-        if trimmed.is_empty() {
-            continue;
-        }
-        let Ok(entry): Result<RolloutLine, _> = serde_json::from_str(trimmed) else {
-            continue;
-        };
-        match entry.item {
-            RolloutItem::TurnContext(_) => {
-                api_turn_count += 1;
-            }
-            RolloutItem::Compacted(ci) => {
-                if ci.message == SUMMARY_TEXT {
-                    saw_compacted_summary = true;
-                }
-            }
-            _ => {}
-        }
-    }
-
-    assert!(
-        api_turn_count == 3,
-        "expected three APITurn entries in rollout"
-    );
-    assert!(
-        saw_compacted_summary,
-        "expected a Compacted entry containing the summarizer output"
-    );
 }
--- a/codex-rs/core/tests/suite/fork_conversation.rs
+++ b/codex-rs/core/tests/suite/fork_conversation.rs
@@ -1,16 +1,12 @@
 use codex_core::CodexAuth;
-use codex_core::ContentItem;
 use codex_core::ConversationManager;
 use codex_core::ModelProviderInfo;
 use codex_core::NewConversation;
-use codex_core::ResponseItem;
 use codex_core::built_in_model_providers;
-use codex_core::protocol::ConversationPathResponseEvent;
+use codex_core::protocol::ConversationHistoryResponseEvent;
 use codex_core::protocol::EventMsg;
 use codex_core::protocol::InputItem;
 use codex_core::protocol::Op;
-use codex_core::protocol::RolloutItem;
-use codex_core::protocol::RolloutLine;
 use core_test_support::load_default_config_for_test;
 use core_test_support::wait_for_event;
 use tempfile::TempDir;
@@ -75,121 +71,84 @@ async fn fork_conversation_twice_drops_to_first_message() {
        let _ = wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
    }

-    // Request history from the base conversation to obtain rollout path.
-    codex.submit(Op::GetPath).await.unwrap();
+    // Request history from the base conversation.
+    codex.submit(Op::GetHistory).await.unwrap();
    let base_history =
-        wait_for_event(&codex, |ev| matches!(ev, EventMsg::ConversationPath(_))).await;
-    let base_path = match &base_history {
-        EventMsg::ConversationPath(ConversationPathResponseEvent { path, .. }) => path.clone(),
+        wait_for_event(&codex, |ev| matches!(ev, EventMsg::ConversationHistory(_))).await;
+
+    // Capture entries from the base history and compute expected prefixes after each fork.
+    let entries_after_three = match &base_history {
+        EventMsg::ConversationHistory(ConversationHistoryResponseEvent { entries, .. }) => {
+            entries.clone()
+        }
        _ => panic!("expected ConversationHistory event"),
    };
+    // History layout for this test:
+    // [0] user instructions,
+    // [1] environment context,
+    // [2] "first" user message,
+    // [3] "second" user message,
+    // [4] "third" user message.

-    // GetHistory flushes before returning the path; no wait needed.
+    // Fork 1: drops the last user message and everything after.
+    let expected_after_first = vec![
+        entries_after_three[0].clone(),
+        entries_after_three[1].clone(),
+        entries_after_three[2].clone(),
+        entries_after_three[3].clone(),
+    ];

-    // Helper: read rollout items (excluding SessionMeta) from a JSONL path.
-    let read_items = |p: &std::path::Path| -> Vec<RolloutItem> {
-        let text = std::fs::read_to_string(p).expect("read rollout file");
-        let mut items: Vec<RolloutItem> = Vec::new();
-        for line in text.lines() {
-            if line.trim().is_empty() {
-                continue;
-            }
-            let v: serde_json::Value = serde_json::from_str(line).expect("jsonl line");
-            let rl: RolloutLine = serde_json::from_value(v).expect("rollout line");
-            match rl.item {
-                RolloutItem::SessionMeta(_) => {}
-                other => items.push(other),
-            }
-        }
-        items
-    };
+    // Fork 2: drops the last user message and everything after.
+    // [0] user instructions,
+    // [1] environment context,
+    // [2] "first" user message,
+    let expected_after_second = vec![
+        entries_after_three[0].clone(),
+        entries_after_three[1].clone(),
+        entries_after_three[2].clone(),
+    ];

-    // Compute expected prefixes after each fork by truncating base rollout at nth-from-last user input.
-    let base_items = read_items(&base_path);
-    let find_user_input_positions = |items: &[RolloutItem]| -> Vec<usize> {
-        let mut pos = Vec::new();
-        for (i, it) in items.iter().enumerate() {
-            if let RolloutItem::ResponseItem(ResponseItem::Message { role, content, .. }) = it
-                && role == "user"
-            {
-                // Consider any user message as an input boundary; recorder stores both EventMsg and ResponseItem.
-                // We specifically look for input items, which are represented as ContentItem::InputText.
-                if content
-                    .iter()
-                    .any(|c| matches!(c, ContentItem::InputText { .. }))
-                {
-                    pos.push(i);
-                }
-            }
-        }
-        pos
-    };
-    let user_inputs = find_user_input_positions(&base_items);
-
-    // After dropping last user input (n=1), cut strictly before that input if present, else empty.
-    let cut1 = user_inputs
-        .get(user_inputs.len().saturating_sub(1))
-        .copied()
-        .unwrap_or(0);
-    let expected_after_first: Vec<RolloutItem> = base_items[..cut1].to_vec();
-
-    // After dropping again (n=1 on fork1), compute expected relative to fork1's rollout.
-
-    // Fork once with n=1 → drops the last user input and everything after.
+    // Fork once with n=1 → drops the last user message and everything after.
    let NewConversation {
        conversation: codex_fork1,
        ..
    } = conversation_manager
-        .fork_conversation(1, config_for_fork.clone(), base_path.clone())
+        .fork_conversation(entries_after_three.clone(), 1, config_for_fork.clone())
        .await
        .expect("fork 1");

-    codex_fork1.submit(Op::GetPath).await.unwrap();
+    codex_fork1.submit(Op::GetHistory).await.unwrap();
    let fork1_history = wait_for_event(&codex_fork1, |ev| {
-        matches!(ev, EventMsg::ConversationPath(_))
+        matches!(ev, EventMsg::ConversationHistory(_))
    })
    .await;
-    let fork1_path = match &fork1_history {
-        EventMsg::ConversationPath(ConversationPathResponseEvent { path, .. }) => path.clone(),
+    let entries_after_first_fork = match &fork1_history {
+        EventMsg::ConversationHistory(ConversationHistoryResponseEvent { entries, .. }) => {
+            assert!(matches!(
+                fork1_history,
+                EventMsg::ConversationHistory(ConversationHistoryResponseEvent { ref entries, .. }) if *entries == expected_after_first
+            ));
+            entries.clone()
+        }
        _ => panic!("expected ConversationHistory event after first fork"),
    };

-    // GetHistory on fork1 flushed; the file is ready.
-    let fork1_items = read_items(&fork1_path);
-    pretty_assertions::assert_eq!(
-        serde_json::to_value(&fork1_items).unwrap(),
-        serde_json::to_value(&expected_after_first).unwrap()
-    );
-
    // Fork again with n=1 → drops the (new) last user message, leaving only the first.
    let NewConversation {
        conversation: codex_fork2,
        ..
    } = conversation_manager
-        .fork_conversation(1, config_for_fork.clone(), fork1_path.clone())
+        .fork_conversation(entries_after_first_fork.clone(), 1, config_for_fork.clone())
        .await
        .expect("fork 2");

-    codex_fork2.submit(Op::GetPath).await.unwrap();
+    codex_fork2.submit(Op::GetHistory).await.unwrap();
    let fork2_history = wait_for_event(&codex_fork2, |ev| {
-        matches!(ev, EventMsg::ConversationPath(_))
+        matches!(ev, EventMsg::ConversationHistory(_))
    })
    .await;
-    let fork2_path = match &fork2_history {
-        EventMsg::ConversationPath(ConversationPathResponseEvent { path, .. }) => path.clone(),
-        _ => panic!("expected ConversationHistory event after second fork"),
-    };
-    // GetHistory on fork2 flushed; the file is ready.
-    let fork1_items = read_items(&fork1_path);
-    let fork1_user_inputs = find_user_input_positions(&fork1_items);
-    let cut_last_on_fork1 = fork1_user_inputs
-        .get(fork1_user_inputs.len().saturating_sub(1))
-        .copied()
-        .unwrap_or(0);
-    let expected_after_second: Vec<RolloutItem> = fork1_items[..cut_last_on_fork1].to_vec();
-    let fork2_items = read_items(&fork2_path);
-    pretty_assertions::assert_eq!(
-        serde_json::to_value(&fork2_items).unwrap(),
-        serde_json::to_value(&expected_after_second).unwrap()
-    );
+    assert!(matches!(
+        fork2_history,
+        EventMsg::ConversationHistory(ConversationHistoryResponseEvent { ref entries, .. }) if *entries == expected_after_second
+    ));
 }
--- a/codex-rs/core/tests/suite/mod.rs
+++ b/codex-rs/core/tests/suite/mod.rs
@@ -7,7 +7,6 @@ mod exec;
 mod exec_stream_events;
 mod fork_conversation;
 mod live_cli;
-mod model_overrides;
 mod prompt_caching;
 mod seatbelt;
 mod stream_error_allows_next_turn;
--- a/codex-rs/core/tests/suite/model_overrides.rs
+++ b/codex-rs/core/tests/suite/model_overrides.rs
@@ -1,92 +0,0 @@
-use codex_core::CodexAuth;
-use codex_core::ConversationManager;
-use codex_core::protocol::EventMsg;
-use codex_core::protocol::Op;
-use codex_core::protocol_config_types::ReasoningEffort;
-use core_test_support::load_default_config_for_test;
-use core_test_support::wait_for_event;
-use pretty_assertions::assert_eq;
-use tempfile::TempDir;
-
-const CONFIG_TOML: &str = "config.toml";
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn override_turn_context_does_not_persist_when_config_exists() {
-    let codex_home = TempDir::new().unwrap();
-    let config_path = codex_home.path().join(CONFIG_TOML);
-    let initial_contents = "model = \"gpt-4o\"\n";
-    tokio::fs::write(&config_path, initial_contents)
-        .await
-        .expect("seed config.toml");
-
-    let mut config = load_default_config_for_test(&codex_home);
-    config.model = "gpt-4o".to_string();
-
-    let conversation_manager =
-        ConversationManager::with_auth(CodexAuth::from_api_key("Test API Key"));
-    let codex = conversation_manager
-        .new_conversation(config)
-        .await
-        .expect("create conversation")
-        .conversation;
-
-    codex
-        .submit(Op::OverrideTurnContext {
-            cwd: None,
-            approval_policy: None,
-            sandbox_policy: None,
-            model: Some("o3".to_string()),
-            effort: Some(ReasoningEffort::High),
-            summary: None,
-        })
-        .await
-        .expect("submit override");
-
-    codex.submit(Op::Shutdown).await.expect("request shutdown");
-    wait_for_event(&codex, |ev| matches!(ev, EventMsg::ShutdownComplete)).await;
-
-    let contents = tokio::fs::read_to_string(&config_path)
-        .await
-        .expect("read config.toml after override");
-    assert_eq!(contents, initial_contents);
-}
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn override_turn_context_does_not_create_config_file() {
-    let codex_home = TempDir::new().unwrap();
-    let config_path = codex_home.path().join(CONFIG_TOML);
-    assert!(
-        !config_path.exists(),
-        "test setup should start without config"
-    );
-
-    let config = load_default_config_for_test(&codex_home);
-
-    let conversation_manager =
-        ConversationManager::with_auth(CodexAuth::from_api_key("Test API Key"));
-    let codex = conversation_manager
-        .new_conversation(config)
-        .await
-        .expect("create conversation")
-        .conversation;
-
-    codex
-        .submit(Op::OverrideTurnContext {
-            cwd: None,
-            approval_policy: None,
-            sandbox_policy: None,
-            model: Some("o3".to_string()),
-            effort: Some(ReasoningEffort::Medium),
-            summary: None,
-        })
-        .await
-        .expect("submit override");
-
-    codex.submit(Op::Shutdown).await.expect("request shutdown");
-    wait_for_event(&codex, |ev| matches!(ev, EventMsg::ShutdownComplete)).await;
-
-    assert!(
-        !config_path.exists(),
-        "override should not create config.toml"
-    );
-}
--- a/codex-rs/core/tests/suite/prompt_caching.rs
+++ b/codex-rs/core/tests/suite/prompt_caching.rs
@@ -17,6 +17,7 @@ use core_test_support::load_default_config_for_test;
 use core_test_support::load_sse_fixture_with_id;
 use core_test_support::wait_for_event;
 use tempfile::TempDir;
+use uuid::Uuid;
 use wiremock::Mock;
 use wiremock::MockServer;
 use wiremock::ResponseTemplate;
@@ -269,14 +270,9 @@ async fn prefixes_context_and_instructions_once_and_consistently_across_requests
    let requests = server.received_requests().await.unwrap();
    assert_eq!(requests.len(), 2, "expected two POST requests");

-    let shell = default_user_shell().await;
-    let shell_line = match shell.name() {
-        Some(name) => format!("  <shell>{name}</shell>\n"),
-        None => String::new(),
-    };
+    let shell = default_user_shell(Uuid::new_v4(), codex_home.path()).await;

-    // Per-turn environment context includes the shell tag.
-    let expected_env_text_turn = format!(
+    let expected_env_text = format!(
        r#"<environment_context>
  <cwd>{}</cwd>
  <approval_policy>on-request</approval_policy>
@@ -284,15 +280,18 @@ async fn prefixes_context_and_instructions_once_and_consistently_across_requests
  <network_access>restricted</network_access>
 {}</environment_context>"#,
        cwd.path().to_string_lossy(),
-        shell_line.as_str(),
+        match shell.name() {
+            Some(name) => format!("  <shell>{name}</shell>\n"),
+            None => String::new(),
+        }
    );
    let expected_ui_text =
        "<user_instructions>\n\nbe consistent and helpful\n\n</user_instructions>";

-    let expected_env_msg_turn = serde_json::json!({
+    let expected_env_msg = serde_json::json!({
        "type": "message",
        "role": "user",
-        "content": [ { "type": "input_text", "text": expected_env_text_turn } ]
+        "content": [ { "type": "input_text", "text": expected_env_text } ]
    });
    let expected_ui_msg = serde_json::json!({
        "type": "message",
@@ -306,29 +305,11 @@ async fn prefixes_context_and_instructions_once_and_consistently_across_requests
        "content": [ { "type": "input_text", "text": "hello 1" } ]
    });
    let body1 = requests[0].body_json::<serde_json::Value>().unwrap();
-    let body1_input = body1["input"].as_array().unwrap();
    assert_eq!(
        body1["input"],
-        serde_json::json!([
-            expected_ui_msg,
-            expected_env_msg_turn,
-            expected_user_message_1
-        ])
+        serde_json::json!([expected_ui_msg, expected_env_msg, expected_user_message_1])
    );

-    let env_texts: Vec<&str> = body1_input
-        .iter()
-        .filter_map(|msg| {
-            msg.get("content")
-                .and_then(|content| content.as_array())
-                .and_then(|content| content.first())
-                .and_then(|item| item.get("text"))
-                .and_then(|text| text.as_str())
-        })
-        .filter(|text| text.starts_with("<environment_context>"))
-        .collect();
-    assert_eq!(env_texts, vec![expected_env_text_turn.as_str()]);
-
    let expected_user_message_2 = serde_json::json!({
        "type": "message",
        "role": "user",
@@ -338,7 +319,7 @@ async fn prefixes_context_and_instructions_once_and_consistently_across_requests
    let expected_body2 = serde_json::json!(
        [
            body1["input"].as_array().unwrap().as_slice(),
-            [expected_env_msg_turn, expected_user_message_2].as_slice(),
+            [expected_user_message_2].as_slice(),
        ]
        .concat()
    );
@@ -443,29 +424,14 @@ async fn overrides_turn_context_but_keeps_cached_prefix_and_key_constant() {
        "role": "user",
        "content": [ { "type": "input_text", "text": "hello 2" } ]
    });
-    let shell = default_user_shell().await;
-    let shell_line = match shell.name() {
-        Some(name) => format!("  <shell>{name}</shell>\n"),
-        None => String::new(),
-    };
-
    // After overriding the turn context, the environment context should be emitted again
    // reflecting the new approval policy and sandbox settings. Omit cwd because it did
    // not change.
-    let expected_env_text_2 = format!(
-        r#"<environment_context>
-  <cwd>{}</cwd>
+    let expected_env_text_2 = r#"<environment_context>
  <approval_policy>never</approval_policy>
  <sandbox_mode>workspace-write</sandbox_mode>
  <network_access>enabled</network_access>
-  <writable_roots>
-    <root>{}</root>
-  </writable_roots>
-{}</environment_context>"#,
-        cwd.path().to_string_lossy(),
-        writable.path().to_string_lossy(),
-        shell_line.as_str()
-    );
+</environment_context>"#;
    let expected_env_msg_2 = serde_json::json!({
        "type": "message",
        "role": "user",
@@ -575,165 +541,12 @@ async fn per_turn_overrides_keep_cached_prefix_and_key_constant() {
        "role": "user",
        "content": [ { "type": "input_text", "text": "hello 2" } ]
    });
-    let shell = default_user_shell().await;
-    let shell_line = match shell.name() {
-        Some(name) => format!("  <shell>{name}</shell>\n"),
-        None => String::new(),
-    };
-    let expected_env_text_2 = format!(
-        r#"<environment_context>
-  <cwd>{}</cwd>
-  <approval_policy>never</approval_policy>
-  <sandbox_mode>workspace-write</sandbox_mode>
-  <network_access>enabled</network_access>
-  <writable_roots>
-    <root>{}</root>
-  </writable_roots>
-{}</environment_context>"#,
-        new_cwd.path().to_string_lossy(),
-        writable.path().to_string_lossy(),
-        shell_line.as_str()
-    );
-    let expected_env_msg_2 = serde_json::json!({
-        "type": "message",
-        "role": "user",
-        "content": [ { "type": "input_text", "text": expected_env_text_2 } ]
-    });
    let expected_body2 = serde_json::json!(
        [
            body1["input"].as_array().unwrap().as_slice(),
-            [expected_env_msg_2, expected_user_message_2].as_slice(),
+            [expected_user_message_2].as_slice(),
        ]
        .concat()
    );
    assert_eq!(body2["input"], expected_body2);
 }
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn tools_stable_across_all_approval_policy_transitions() {
-    use pretty_assertions::assert_eq;
-
-    let server = MockServer::start().await;
-
-    let sse = sse_completed("resp");
-    let template = ResponseTemplate::new(200)
-        .insert_header("content-type", "text/event-stream")
-        .set_body_raw(sse, "text/event-stream");
-
-    // Build all transitions FROM each to each other (exclude self transitions)
-    let policies = vec![
-        AskForApproval::UnlessTrusted,
-        AskForApproval::OnFailure,
-        AskForApproval::OnRequest,
-        AskForApproval::Never,
-    ];
-    let mut transitions: Vec<(AskForApproval, AskForApproval)> = Vec::new();
-    for &from in &policies {
-        for &to in &policies {
-            if from != to {
-                transitions.push((from, to));
-            }
-        }
-    }
-
-    // Expect 2 POSTs per transition
-    Mock::given(method("POST"))
-        .and(path("/v1/responses"))
-        .respond_with(template)
-        .expect((transitions.len() * 2) as u64)
-        .mount(&server)
-        .await;
-
-    let model_provider = ModelProviderInfo {
-        base_url: Some(format!("{}/v1", server.uri())),
-        ..built_in_model_providers()["openai"].clone()
-    };
-
-    let cwd = TempDir::new().unwrap();
-    let codex_home = TempDir::new().unwrap();
-    let mut config = load_default_config_for_test(&codex_home);
-    config.cwd = cwd.path().to_path_buf();
-    config.model_provider = model_provider;
-    config.user_instructions = Some("be consistent and helpful".to_string());
-    // Keep tools stable and minimal
-    config.include_plan_tool = false;
-    config.include_apply_patch_tool = false;
-    config.tools_web_search_request = false;
-    config.use_experimental_unified_exec_tool = true; // policy-independent tool
-
-    let conversation_manager =
-        ConversationManager::with_auth(CodexAuth::from_api_key("Test API Key"));
-    let codex = conversation_manager
-        .new_conversation(config)
-        .await
-        .expect("create new conversation")
-        .conversation;
-
-    for (i, (from, to)) in transitions.iter().enumerate() {
-        // Ensure a known starting policy for this pair
-        codex
-            .submit(Op::OverrideTurnContext {
-                cwd: None,
-                approval_policy: Some(*from),
-                sandbox_policy: None,
-                model: None,
-                effort: None,
-                summary: None,
-            })
-            .await
-            .unwrap();
-
-        codex
-            .submit(Op::UserInput {
-                items: vec![InputItem::Text {
-                    text: format!("turn {i}-a"),
-                }],
-            })
-            .await
-            .unwrap();
-        wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
-
-        // Override to the target policy and send next turn
-        codex
-            .submit(Op::OverrideTurnContext {
-                cwd: None,
-                approval_policy: Some(*to),
-                sandbox_policy: None,
-                model: None,
-                effort: None,
-                summary: None,
-            })
-            .await
-            .unwrap();
-
-        codex
-            .submit(Op::UserInput {
-                items: vec![InputItem::Text {
-                    text: format!("turn {i}-b"),
-                }],
-            })
-            .await
-            .unwrap();
-        wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
-    }
-
-    // Verify tool arrays are identical across each pair of requests
-    let requests = server.received_requests().await.unwrap();
-    assert_eq!(
-        requests.len(),
-        transitions.len() * 2,
-        "expected 2 requests per transition"
-    );
-
-    for i in 0..transitions.len() {
-        let body_a = requests[2 * i].body_json::<serde_json::Value>().unwrap();
-        let body_b = requests[2 * i + 1]
-            .body_json::<serde_json::Value>()
-            .unwrap();
-        assert_eq!(
-            body_a["tools"], body_b["tools"],
-            "tools changed between requests for transition #{i}: {:?}",
-            transitions[i]
-        );
-    }
-}
--- a/codex-rs/core/tests/unexpected_status_no_retry.rs
+++ b/codex-rs/core/tests/unexpected_status_no_retry.rs
@@ -0,0 +1,88 @@
+use std::time::Duration;
+
+use codex_core::ConversationManager;
+use codex_core::ModelProviderInfo;
+use codex_core::WireApi;
+use codex_core::protocol::EventMsg;
+use codex_core::protocol::InputItem;
+use codex_core::protocol::Op;
+use codex_core::spawn::CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR;
+use codex_login::CodexAuth;
+use core_test_support::load_default_config_for_test;
+use core_test_support::wait_for_event_with_timeout;
+use serde_json::json;
+use tempfile::TempDir;
+use wiremock::Mock;
+use wiremock::MockServer;
+use wiremock::ResponseTemplate;
+use wiremock::matchers::method;
+use wiremock::matchers::path;
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn fails_fast_on_unexpected_status() {
+    if std::env::var(CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR).is_ok() {
+        println!(
+            "Skipping test because it cannot execute when network is disabled in a Codex sandbox."
+        );
+        return;
+    }
+
+    let server = MockServer::start().await;
+
+    let err_body = json!({
+        "error": {"message": "bad request"}
+    });
+    let tmpl = ResponseTemplate::new(400)
+        .insert_header("content-type", "application/json")
+        .set_body_string(err_body.to_string());
+
+    Mock::given(method("POST"))
+        .and(path("/v1/responses"))
+        .respond_with(tmpl)
+        .expect(1)
+        .mount(&server)
+        .await;
+
+    let provider = ModelProviderInfo {
+        name: "openai".into(),
+        base_url: Some(format!("{}/v1", server.uri())),
+        env_key: Some("PATH".into()),
+        env_key_instructions: None,
+        wire_api: WireApi::Responses,
+        query_params: None,
+        http_headers: None,
+        env_http_headers: None,
+        request_max_retries: Some(0),
+        stream_max_retries: Some(3),
+        stream_idle_timeout_ms: Some(2000),
+        requires_openai_auth: false,
+    };
+
+    let home = TempDir::new().unwrap();
+    let mut config = load_default_config_for_test(&home);
+    config.model_provider = provider;
+
+    let conversation_manager =
+        ConversationManager::with_auth(CodexAuth::from_api_key("Test API Key"));
+    let codex = conversation_manager
+        .new_conversation(config)
+        .await
+        .unwrap()
+        .conversation;
+
+    codex
+        .submit(Op::UserInput {
+            items: vec![InputItem::Text {
+                text: "hello".into(),
+            }],
+        })
+        .await
+        .unwrap();
+
+    wait_for_event_with_timeout(
+        &codex,
+        |ev| matches!(ev, EventMsg::Error(_)),
+        Duration::from_secs(5),
+    )
+    .await;
+}
--- a/codex-rs/exec/src/event_processor_with_human_output.rs
+++ b/codex-rs/exec/src/event_processor_with_human_output.rs
@@ -280,7 +280,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                parsed_cmd: _,
            }) => {
                self.call_id_to_command.insert(
-                    call_id,
+                    call_id.clone(),
                    ExecCommandBegin {
                        command: command.clone(),
                    },
@@ -382,7 +382,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                // Store metadata so we can calculate duration later when we
                // receive the corresponding PatchApplyEnd event.
                self.call_id_to_patch.insert(
-                    call_id,
+                    call_id.clone(),
                    PatchApplyBegin {
                        start_time: Instant::now(),
                        auto_approved,
@@ -520,11 +520,9 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                let SessionConfiguredEvent {
                    session_id: conversation_id,
                    model,
-                    reasoning_effort: _,
                    history_log_id: _,
                    history_entry_count: _,
                    initial_messages: _,
-                    rollout_path: _,
                } = session_configured_event;

                ts_println!(
@@ -560,7 +558,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                }
            },
            EventMsg::ShutdownComplete => return CodexStatus::Shutdown,
-            EventMsg::ConversationPath(_) => {}
+            EventMsg::ConversationHistory(_) => {}
            EventMsg::UserMessage(_) => {}
        }
        CodexStatus::Running
--- a/codex-rs/exec/src/lib.rs
+++ b/codex-rs/exec/src/lib.rs
@@ -187,8 +187,11 @@ pub async fn run_main(cli: Cli, codex_linux_sandbox_exe: Option<PathBuf>) -> any
        std::process::exit(1);
    }

-    let conversation_manager =
-        ConversationManager::new(AuthManager::shared(config.codex_home.clone()));
+    let conversation_manager = ConversationManager::new(AuthManager::shared(
+        config.codex_home.clone(),
+        config.preferred_auth_method,
+        config.responses_originator_header.clone(),
+    ));
    let NewConversation {
        conversation_id: _,
        conversation,
--- a/codex-rs/exec/tests/suite/common.rs
+++ b/codex-rs/exec/tests/suite/common.rs
@@ -61,7 +61,7 @@ pub(crate) async fn run_e2e_exec_test(cwd: &Path, response_streams: Vec<String>)
        .context("should find binary for codex-exec")
        .expect("should find binary for codex-exec")
        .current_dir(cwd.clone())
-        .env("CODEX_HOME", cwd)
+        .env("CODEX_HOME", cwd.clone())
        .env("OPENAI_API_KEY", "dummy")
        .env("OPENAI_BASE_URL", format!("{uri}/v1"))
        .arg("--skip-git-repo-check")
--- a/codex-rs/execpolicy/src/execv_checker.rs
+++ b/codex-rs/execpolicy/src/execv_checker.rs
@@ -88,7 +88,7 @@ impl ExecvChecker {
        let mut program = valid_exec.program.to_string();
        for system_path in valid_exec.system_path {
            if is_executable_file(&system_path) {
-                program = system_path;
+                program = system_path.to_string();
                break;
            }
        }
@@ -196,7 +196,7 @@ system_path=[{fake_cp:?}]
        let checker = setup(&fake_cp);
        let exec_call = ExecCall {
            program: "cp".into(),
-            args: vec![source, dest.clone()],
+            args: vec![source.clone(), dest.clone()],
        };
        let valid_exec = match checker.r#match(&exec_call)? {
            MatchedExec::Match { exec } => exec,
@@ -207,7 +207,7 @@ system_path=[{fake_cp:?}]
        assert_eq!(
            checker.check(valid_exec.clone(), &cwd, &[], &[]),
            Err(ReadablePathNotInReadableFolders {
-                file: source_path,
+                file: source_path.clone(),
                folders: vec![]
            }),
        );
@@ -229,7 +229,7 @@ system_path=[{fake_cp:?}]
        // Both readable and writeable folders specified.
        assert_eq!(
            checker.check(
-                valid_exec,
+                valid_exec.clone(),
                &cwd,
                std::slice::from_ref(&root_path),
                std::slice::from_ref(&root_path)
@@ -241,7 +241,7 @@ system_path=[{fake_cp:?}]
        // folders.
        let exec_call_folders_as_args = ExecCall {
            program: "cp".into(),
-            args: vec![root.clone(), root],
+            args: vec![root.clone(), root.clone()],
        };
        let valid_exec_call_folders_as_args = match checker.r#match(&exec_call_folders_as_args)? {
            MatchedExec::Match { exec } => exec,
@@ -254,7 +254,7 @@ system_path=[{fake_cp:?}]
                std::slice::from_ref(&root_path),
                std::slice::from_ref(&root_path)
            ),
-            Ok(cp),
+            Ok(cp.clone()),
        );

        // Specify a parent of a readable folder as input.
--- a/codex-rs/execpolicy/src/policy_parser.rs
+++ b/codex-rs/execpolicy/src/policy_parser.rs
@@ -104,7 +104,7 @@ impl PolicyBuilder {
        info!("adding program spec: {program_spec:?}");
        let name = program_spec.program.clone();
        let mut programs = self.programs.borrow_mut();
-        programs.insert(name, program_spec);
+        programs.insert(name.clone(), program_spec);
    }

    fn add_forbidden_substrings(&self, substrings: &[String]) {
--- a/codex-rs/justfile
+++ b/codex-rs/justfile
@@ -31,13 +31,6 @@ install:
    rustup show active-toolchain
    cargo fetch

-# Run `cargo nextest` since it's faster than `cargo test`, though including
-# --no-fail-fast is important to ensure all tests are run.
-#
-# Run `cargo install cargo-nextest` if you don't have it installed.
-test:
-    cargo nextest run --no-fail-fast
-
 # Run the MCP server
 mcp-server-run *args:
    cargo run -p codex-mcp-server -- "$@"
--- a/codex-rs/login/src/server.rs
+++ b/codex-rs/login/src/server.rs
@@ -16,7 +16,6 @@ use base64::Engine;
 use chrono::Utc;
 use codex_core::auth::AuthDotJson;
 use codex_core::auth::get_auth_file;
-use codex_core::default_client::ORIGINATOR;
 use codex_core::token_data::TokenData;
 use codex_core::token_data::parse_id_token;
 use rand::RngCore;
@@ -36,17 +35,19 @@ pub struct ServerOptions {
    pub port: u16,
    pub open_browser: bool,
    pub force_state: Option<String>,
+    pub originator: String,
 }

 impl ServerOptions {
-    pub fn new(codex_home: PathBuf, client_id: String) -> Self {
+    pub fn new(codex_home: PathBuf, client_id: String, originator: String) -> Self {
        Self {
            codex_home,
-            client_id,
+            client_id: client_id.to_string(),
            issuer: DEFAULT_ISSUER.to_string(),
            port: DEFAULT_PORT,
            open_browser: true,
            force_state: None,
+            originator,
        }
    }
 }
@@ -102,7 +103,14 @@ pub fn run_login_server(opts: ServerOptions) -> io::Result<LoginServer> {
    let server = Arc::new(server);

    let redirect_uri = format!("http://localhost:{actual_port}/auth/callback");
-    let auth_url = build_authorize_url(&opts.issuer, &opts.client_id, &redirect_uri, &pkce, &state);
+    let auth_url = build_authorize_url(
+        &opts.issuer,
+        &opts.client_id,
+        &redirect_uri,
+        &pkce,
+        &state,
+        &opts.originator,
+    );

    if opts.open_browser {
        let _ = webbrowser::open(&auth_url);
@@ -126,7 +134,7 @@ pub fn run_login_server(opts: ServerOptions) -> io::Result<LoginServer> {
    let shutdown_notify = Arc::new(tokio::sync::Notify::new());
    let server_handle = {
        let shutdown_notify = shutdown_notify.clone();
-        let server = server;
+        let server = server.clone();
        tokio::spawn(async move {
            let result = loop {
                tokio::select! {
@@ -303,6 +311,7 @@ fn build_authorize_url(
    redirect_uri: &str,
    pkce: &PkceCodes,
    state: &str,
+    originator: &str,
 ) -> String {
    let query = vec![
        ("response_type", "code"),
@@ -314,7 +323,7 @@ fn build_authorize_url(
        ("id_token_add_organizations", "true"),
        ("codex_cli_simplified_flow", "true"),
        ("state", state),
-        ("originator", ORIGINATOR.value.as_str()),
+        ("originator", originator),
    ];
    let qs = query
        .into_iter()
--- a/codex-rs/login/tests/suite/login_server_e2e.rs
+++ b/codex-rs/login/tests/suite/login_server_e2e.rs
@@ -102,6 +102,7 @@ async fn end_to_end_login_flow_persists_auth_json() {
        port: 0,
        open_browser: false,
        force_state: Some(state),
+        originator: "test_originator".to_string(),
    };
    let server = run_login_server(opts).unwrap();
    let login_port = server.actual_port;
@@ -160,6 +161,7 @@ async fn creates_missing_codex_home_dir() {
        port: 0,
        open_browser: false,
        force_state: Some(state),
+        originator: "test_originator".to_string(),
    };
    let server = run_login_server(opts).unwrap();
    let login_port = server.actual_port;
@@ -200,6 +202,7 @@ async fn cancels_previous_login_server_when_port_is_in_use() {
        port: 0,
        open_browser: false,
        force_state: Some("cancel_state".to_string()),
+        originator: "test_originator".to_string(),
    };

    let first_server = run_login_server(first_opts).unwrap();
@@ -218,6 +221,7 @@ async fn cancels_previous_login_server_when_port_is_in_use() {
        port: login_port,
        open_browser: false,
        force_state: Some("cancel_state_2".to_string()),
+        originator: "test_originator".to_string(),
    };

    let second_server = run_login_server(second_opts).unwrap();
--- a/codex-rs/mcp-client/src/main.rs
+++ b/codex-rs/mcp-client/src/main.rs
@@ -64,9 +64,6 @@ async fn main() -> Result<()> {
            name: "codex-mcp-client".to_owned(),
            version: env!("CARGO_PKG_VERSION").to_owned(),
            title: Some("Codex".to_string()),
-            // This field is used by Codex when it is an MCP server: it should
-            // not be used when Codex is an MCP client.
-            user_agent: None,
        },
        protocol_version: MCP_SCHEMA_VERSION.to_owned(),
    };
--- a/codex-rs/mcp-server/Cargo.toml
+++ b/codex-rs/mcp-server/Cargo.toml
@@ -40,9 +40,7 @@ uuid = { version = "1", features = ["serde", "v4"] }

 [dev-dependencies]
 assert_cmd = "2"
-base64 = "0.22"
 mcp_test_support = { path = "tests/common" }
-os_info = "3.12.0"
 pretty_assertions = "1.4.1"
 tempfile = "3"
 wiremock = "0.6"
--- a/codex-rs/mcp-server/src/codex_message_processor.rs
+++ b/codex-rs/mcp-server/src/codex_message_processor.rs
@@ -11,16 +11,10 @@ use codex_core::NewConversation;
 use codex_core::RolloutRecorder;
 use codex_core::SessionMeta;
 use codex_core::auth::CLIENT_ID;
-use codex_core::auth::get_auth_file;
-use codex_core::auth::login_with_api_key;
-use codex_core::auth::try_read_auth_json;
 use codex_core::config::Config;
 use codex_core::config::ConfigOverrides;
 use codex_core::config::ConfigToml;
 use codex_core::config::load_config_as_toml;
-use codex_core::config_edit::CONFIG_KEY_EFFORT;
-use codex_core::config_edit::CONFIG_KEY_MODEL;
-use codex_core::config_edit::persist_non_null_overrides;
 use codex_core::default_client::get_codex_user_agent;
 use codex_core::exec::ExecParams;
 use codex_core::exec_env::create_env;
@@ -41,8 +35,7 @@ use codex_protocol::mcp_protocol::AddConversationListenerParams;
 use codex_protocol::mcp_protocol::AddConversationSubscriptionResponse;
 use codex_protocol::mcp_protocol::ApplyPatchApprovalParams;
 use codex_protocol::mcp_protocol::ApplyPatchApprovalResponse;
-use codex_protocol::mcp_protocol::ArchiveConversationParams;
-use codex_protocol::mcp_protocol::ArchiveConversationResponse;
+use codex_protocol::mcp_protocol::AuthMode;
 use codex_protocol::mcp_protocol::AuthStatusChangeNotification;
 use codex_protocol::mcp_protocol::ClientRequest;
 use codex_protocol::mcp_protocol::ConversationId;
@@ -60,8 +53,6 @@ use codex_protocol::mcp_protocol::InterruptConversationParams;
 use codex_protocol::mcp_protocol::InterruptConversationResponse;
 use codex_protocol::mcp_protocol::ListConversationsParams;
 use codex_protocol::mcp_protocol::ListConversationsResponse;
-use codex_protocol::mcp_protocol::LoginApiKeyParams;
-use codex_protocol::mcp_protocol::LoginApiKeyResponse;
 use codex_protocol::mcp_protocol::LoginChatGptCompleteNotification;
 use codex_protocol::mcp_protocol::LoginChatGptResponse;
 use codex_protocol::mcp_protocol::NewConversationParams;
@@ -74,9 +65,6 @@ use codex_protocol::mcp_protocol::SendUserMessageResponse;
 use codex_protocol::mcp_protocol::SendUserTurnParams;
 use codex_protocol::mcp_protocol::SendUserTurnResponse;
 use codex_protocol::mcp_protocol::ServerNotification;
-use codex_protocol::mcp_protocol::SetDefaultModelParams;
-use codex_protocol::mcp_protocol::SetDefaultModelResponse;
-use codex_protocol::mcp_protocol::UserInfoResponse;
 use codex_protocol::mcp_protocol::UserSavedConfig;
 use codex_protocol::models::ContentItem;
 use codex_protocol::models::ResponseItem;
@@ -85,16 +73,12 @@ use codex_protocol::protocol::USER_MESSAGE_BEGIN;
 use mcp_types::JSONRPCErrorError;
 use mcp_types::RequestId;
 use std::collections::HashMap;
-use std::ffi::OsStr;
 use std::path::PathBuf;
 use std::sync::Arc;
 use std::time::Duration;
-use tokio::select;
 use tokio::sync::Mutex;
 use tokio::sync::oneshot;
 use tracing::error;
-use tracing::info;
-use tracing::warn;
 use uuid::Uuid;

 // Duration before a ChatGPT login attempt is abandoned.
@@ -158,9 +142,6 @@ impl CodexMessageProcessor {
            ClientRequest::ResumeConversation { request_id, params } => {
                self.handle_resume_conversation(request_id, params).await;
            }
-            ClientRequest::ArchiveConversation { request_id, params } => {
-                self.archive_conversation(request_id, params).await;
-            }
            ClientRequest::SendUserMessage { request_id, params } => {
                self.send_user_message(request_id, params).await;
            }
@@ -179,9 +160,6 @@ impl CodexMessageProcessor {
            ClientRequest::GitDiffToRemote { request_id, params } => {
                self.git_diff_to_origin(request_id, params.cwd).await;
            }
-            ClientRequest::LoginApiKey { request_id, params } => {
-                self.login_api_key(request_id, params).await;
-            }
            ClientRequest::LoginChatGpt { request_id } => {
                self.login_chatgpt(request_id).await;
            }
@@ -197,60 +175,25 @@ impl CodexMessageProcessor {
            ClientRequest::GetUserSavedConfig { request_id } => {
                self.get_user_saved_config(request_id).await;
            }
-            ClientRequest::SetDefaultModel { request_id, params } => {
-                self.set_default_model(request_id, params).await;
-            }
            ClientRequest::GetUserAgent { request_id } => {
                self.get_user_agent(request_id).await;
            }
-            ClientRequest::UserInfo { request_id } => {
-                self.get_user_info(request_id).await;
-            }
            ClientRequest::ExecOneOffCommand { request_id, params } => {
                self.exec_one_off_command(request_id, params).await;
            }
        }
    }

-    async fn login_api_key(&mut self, request_id: RequestId, params: LoginApiKeyParams) {
-        {
-            let mut guard = self.active_login.lock().await;
-            if let Some(active) = guard.take() {
-                active.drop();
-            }
-        }
-
-        match login_with_api_key(&self.config.codex_home, &params.api_key) {
-            Ok(()) => {
-                self.auth_manager.reload();
-                self.outgoing
-                    .send_response(request_id, LoginApiKeyResponse {})
-                    .await;
-
-                let payload = AuthStatusChangeNotification {
-                    auth_method: self.auth_manager.auth().map(|auth| auth.mode),
-                };
-                self.outgoing
-                    .send_server_notification(ServerNotification::AuthStatusChange(payload))
-                    .await;
-            }
-            Err(err) => {
-                let error = JSONRPCErrorError {
-                    code: INTERNAL_ERROR_CODE,
-                    message: format!("failed to save api key: {err}"),
-                    data: None,
-                };
-                self.outgoing.send_error(request_id, error).await;
-            }
-        }
-    }
-
    async fn login_chatgpt(&mut self, request_id: RequestId) {
        let config = self.config.as_ref();

        let opts = LoginServerOptions {
            open_browser: false,
-            ..LoginServerOptions::new(config.codex_home.clone(), CLIENT_ID.to_string())
+            ..LoginServerOptions::new(
+                config.codex_home.clone(),
+                CLIENT_ID.to_string(),
+                config.responses_originator_header.clone(),
+            )
        };

        enum LoginChatGptReply {
@@ -398,7 +341,7 @@ impl CodexMessageProcessor {
            .await;

        // Send auth status change notification reflecting the current auth mode
-        // after logout.
+        // after logout (which may fall back to API key via env var).
        let current_auth_method = self.auth_manager.auth().map(|auth| auth.mode);
        let payload = AuthStatusChangeNotification {
            auth_method: current_auth_method,
@@ -413,6 +356,7 @@ impl CodexMessageProcessor {
        request_id: RequestId,
        params: codex_protocol::mcp_protocol::GetAuthStatusParams,
    ) {
+        let preferred_auth_method: AuthMode = self.auth_manager.preferred_auth_method();
        let include_token = params.include_token.unwrap_or(false);
        let do_refresh = params.refresh_token.unwrap_or(false);

@@ -420,11 +364,6 @@ impl CodexMessageProcessor {
            tracing::warn!("failed to refresh token while getting auth status: {err}");
        }

-        // Determine whether auth is required based on the active model provider.
-        // If a custom provider is configured with `requires_openai_auth == false`,
-        // then no auth step is required; otherwise, default to requiring auth.
-        let requires_openai_auth = Some(self.config.model_provider.requires_openai_auth);
-
        let response = match self.auth_manager.auth() {
            Some(auth) => {
                let (reported_auth_method, token_opt) = match auth.get_token().await {
@@ -440,14 +379,14 @@ impl CodexMessageProcessor {
                };
                codex_protocol::mcp_protocol::GetAuthStatusResponse {
                    auth_method: reported_auth_method,
+                    preferred_auth_method,
                    auth_token: token_opt,
-                    requires_openai_auth,
                }
            }
            None => codex_protocol::mcp_protocol::GetAuthStatusResponse {
                auth_method: None,
+                preferred_auth_method,
                auth_token: None,
-                requires_openai_auth,
            },
        };

@@ -455,7 +394,7 @@ impl CodexMessageProcessor {
    }

    async fn get_user_agent(&self, request_id: RequestId) {
-        let user_agent = get_codex_user_agent();
+        let user_agent = get_codex_user_agent(Some(&self.config.responses_originator_header));
        let response = GetUserAgentResponse { user_agent };
        self.outgoing.send_response(request_id, response).await;
    }
@@ -495,52 +434,6 @@ impl CodexMessageProcessor {
        self.outgoing.send_response(request_id, response).await;
    }

-    async fn get_user_info(&self, request_id: RequestId) {
-        // Read alleged user email from auth.json (best-effort; not verified).
-        let auth_path = get_auth_file(&self.config.codex_home);
-        let alleged_user_email = match try_read_auth_json(&auth_path) {
-            Ok(auth) => auth.tokens.and_then(|t| t.id_token.email),
-            Err(_) => None,
-        };
-
-        let response = UserInfoResponse { alleged_user_email };
-        self.outgoing.send_response(request_id, response).await;
-    }
-
-    async fn set_default_model(&self, request_id: RequestId, params: SetDefaultModelParams) {
-        let SetDefaultModelParams {
-            model,
-            reasoning_effort,
-        } = params;
-        let effort_str = reasoning_effort.map(|effort| effort.to_string());
-
-        let overrides: [(&[&str], Option<&str>); 2] = [
-            (&[CONFIG_KEY_MODEL], model.as_deref()),
-            (&[CONFIG_KEY_EFFORT], effort_str.as_deref()),
-        ];
-
-        match persist_non_null_overrides(
-            &self.config.codex_home,
-            self.config.active_profile.as_deref(),
-            &overrides,
-        )
-        .await
-        {
-            Ok(()) => {
-                let response = SetDefaultModelResponse {};
-                self.outgoing.send_response(request_id, response).await;
-            }
-            Err(err) => {
-                let error = JSONRPCErrorError {
-                    code: INTERNAL_ERROR_CODE,
-                    message: format!("failed to persist overrides: {err}"),
-                    data: None,
-                };
-                self.outgoing.send_error(request_id, error).await;
-            }
-        }
-    }
-
    async fn exec_one_off_command(&self, request_id: RequestId, params: ExecOneOffCommandParams) {
        tracing::debug!("ExecOneOffCommand params: {params:?}");

@@ -635,8 +528,6 @@ impl CodexMessageProcessor {
                let response = NewConversationResponse {
                    conversation_id,
                    model: session_configured.model,
-                    reasoning_effort: session_configured.reasoning_effort,
-                    rollout_path: session_configured.rollout_path,
                };
                self.outgoing.send_response(request_id, response).await;
            }
@@ -778,141 +669,6 @@ impl CodexMessageProcessor {
        }
    }

-    async fn archive_conversation(&self, request_id: RequestId, params: ArchiveConversationParams) {
-        let ArchiveConversationParams {
-            conversation_id,
-            rollout_path,
-        } = params;
-
-        // Verify that the rollout path is in the sessions directory or else
-        // a malicious client could specify an arbitrary path.
-        let rollout_folder = self.config.codex_home.join(codex_core::SESSIONS_SUBDIR);
-        let canonical_rollout_path = tokio::fs::canonicalize(&rollout_path).await;
-        let canonical_rollout_path = if let Ok(path) = canonical_rollout_path
-            && path.starts_with(&rollout_folder)
-        {
-            path
-        } else {
-            let error = JSONRPCErrorError {
-                code: INVALID_REQUEST_ERROR_CODE,
-                message: format!(
-                    "rollout path `{}` must be in sessions directory",
-                    rollout_path.display()
-                ),
-                data: None,
-            };
-            self.outgoing.send_error(request_id, error).await;
-            return;
-        };
-
-        let required_suffix = format!("{}.jsonl", conversation_id.0);
-        let Some(file_name) = canonical_rollout_path.file_name().map(OsStr::to_owned) else {
-            let error = JSONRPCErrorError {
-                code: INVALID_REQUEST_ERROR_CODE,
-                message: format!(
-                    "rollout path `{}` missing file name",
-                    rollout_path.display()
-                ),
-                data: None,
-            };
-            self.outgoing.send_error(request_id, error).await;
-            return;
-        };
-
-        if !file_name
-            .to_string_lossy()
-            .ends_with(required_suffix.as_str())
-        {
-            let error = JSONRPCErrorError {
-                code: INVALID_REQUEST_ERROR_CODE,
-                message: format!(
-                    "rollout path `{}` does not match conversation id {conversation_id}",
-                    rollout_path.display()
-                ),
-                data: None,
-            };
-            self.outgoing.send_error(request_id, error).await;
-            return;
-        }
-
-        let removed_conversation = self
-            .conversation_manager
-            .remove_conversation(&conversation_id)
-            .await;
-        if let Some(conversation) = removed_conversation {
-            info!("conversation {conversation_id} was active; shutting down");
-            let conversation_clone = conversation.clone();
-            let notify = Arc::new(tokio::sync::Notify::new());
-            let notify_clone = notify.clone();
-
-            // Establish the listener for ShutdownComplete before submitting
-            // Shutdown so it is not missed.
-            let is_shutdown = tokio::spawn(async move {
-                loop {
-                    select! {
-                        _ = notify_clone.notified() => {
-                            break;
-                        }
-                        event = conversation_clone.next_event() => {
-                            if let Ok(event) = event && matches!(event.msg, EventMsg::ShutdownComplete) {
-                                break;
-                            }
-                        }
-                    }
-                }
-            });
-
-            // Request shutdown.
-            match conversation.submit(Op::Shutdown).await {
-                Ok(_) => {
-                    // Successfully submitted Shutdown; wait before proceeding.
-                    select! {
-                        _ = is_shutdown => {
-                            // Normal shutdown: proceed with archive.
-                        }
-                        _ = tokio::time::sleep(Duration::from_secs(10)) => {
-                            warn!("conversation {conversation_id} shutdown timed out; proceeding with archive");
-                            notify.notify_one();
-                        }
-                    }
-                }
-                Err(err) => {
-                    error!("failed to submit Shutdown to conversation {conversation_id}: {err}");
-                    notify.notify_one();
-                    // Perhaps we lost a shutdown race, so let's continue to
-                    // clean up the .jsonl file.
-                }
-            }
-        }
-
-        // Move the .jsonl file to the archived sessions subdir.
-        let result: std::io::Result<()> = async {
-            let archive_folder = self
-                .config
-                .codex_home
-                .join(codex_core::ARCHIVED_SESSIONS_SUBDIR);
-            tokio::fs::create_dir_all(&archive_folder).await?;
-            tokio::fs::rename(&canonical_rollout_path, &archive_folder.join(&file_name)).await?;
-            Ok(())
-        }
-        .await;
-
-        match result {
-            Ok(()) => {
-                let response = ArchiveConversationResponse {};
-                self.outgoing.send_response(request_id, response).await;
-            }
-            Err(err) => {
-                let error = JSONRPCErrorError {
-                    code: INTERNAL_ERROR_CODE,
-                    message: format!("failed to archive conversation: {err}"),
-                    data: None,
-                };
-                self.outgoing.send_error(request_id, error).await;
-            }
-        }
-    }
-
    async fn send_user_message(&self, request_id: RequestId, params: SendUserMessageParams) {
        let SendUserMessageParams {
            conversation_id,
@@ -1354,7 +1110,10 @@ fn extract_conversation_summary(
    head: &[serde_json::Value],
 ) -> Option<ConversationSummary> {
    let session_meta = match head.first() {
-        Some(first_line) => serde_json::from_value::<SessionMeta>(first_line.clone()).ok()?,
+        Some(first_line) => match serde_json::from_value::<SessionMeta>(first_line.clone()) {
+            Ok(session_meta) => session_meta,
+            Err(..) => return None,
+        },
        None => return None,
    };

@@ -1412,10 +1171,6 @@ mod tests {
            json!({
                "id": conversation_id.0,
                "timestamp": timestamp,
-                "cwd": "/",
-                "originator": "codex",
-                "cli_version": "0.0.0",
-                "instructions": null
            }),
            json!({
                "type": "message",
--- a/codex-rs/mcp-server/src/codex_tool_runner.rs
+++ b/codex-rs/mcp-server/src/codex_tool_runner.rs
@@ -222,7 +222,7 @@ async fn run_codex_tool_session_inner(
                    }
                    EventMsg::TaskComplete(TaskCompleteEvent { last_agent_message }) => {
                        let text = match last_agent_message {
-                            Some(msg) => msg,
+                            Some(msg) => msg.clone(),
                            None => "".to_string(),
                        };
                        let result = CallToolResult {
@@ -277,7 +277,7 @@ async fn run_codex_tool_session_inner(
                    | EventMsg::GetHistoryEntryResponse(_)
                    | EventMsg::PlanUpdate(_)
                    | EventMsg::TurnAborted(_)
-                    | EventMsg::ConversationPath(_)
+                    | EventMsg::ConversationHistory(_)
                    | EventMsg::UserMessage(_)
                    | EventMsg::ShutdownComplete => {
                        // For now, we do not do anything extra for these
--- a/codex-rs/mcp-server/src/message_processor.rs
+++ b/codex-rs/mcp-server/src/message_processor.rs
@@ -14,8 +14,6 @@ use codex_protocol::mcp_protocol::ConversationId;
 use codex_core::AuthManager;
 use codex_core::ConversationManager;
 use codex_core::config::Config;
-use codex_core::default_client::USER_AGENT_SUFFIX;
-use codex_core::default_client::get_codex_user_agent;
 use codex_core::protocol::Submission;
 use mcp_types::CallToolRequestParams;
 use mcp_types::CallToolResult;
@@ -56,7 +54,11 @@ impl MessageProcessor {
        config: Arc<Config>,
    ) -> Self {
        let outgoing = Arc::new(outgoing);
-        let auth_manager = AuthManager::shared(config.codex_home.clone());
+        let auth_manager = AuthManager::shared(
+            config.codex_home.clone(),
+            config.preferred_auth_method,
+            config.responses_originator_header.clone(),
+        );
        let conversation_manager = Arc::new(ConversationManager::new(auth_manager.clone()));
        let codex_message_processor = CodexMessageProcessor::new(
            auth_manager,
@@ -209,14 +211,6 @@ impl MessageProcessor {
            return;
        }

-        let client_info = params.client_info;
-        let name = client_info.name;
-        let version = client_info.version;
-        let user_agent_suffix = format!("{name}; {version}");
-        if let Ok(mut suffix) = USER_AGENT_SUFFIX.lock() {
-            *suffix = Some(user_agent_suffix);
-        }
-
        self.initialized = true;

        // Build a minimal InitializeResult. Fill with placeholders.
@@ -237,7 +231,6 @@ impl MessageProcessor {
                name: "codex-mcp-server".to_string(),
                version: env!("CARGO_PKG_VERSION").to_string(),
                title: Some("Codex".to_string()),
-                user_agent: Some(get_codex_user_agent()),
            },
        };

@@ -531,6 +524,7 @@ impl MessageProcessor {

        // Spawn the long-running reply handler.
        tokio::spawn({
+            let codex = codex.clone();
            let outgoing = outgoing.clone();
            let prompt = prompt.clone();
            let running_requests_id_to_codex_uuid = running_requests_id_to_codex_uuid.clone();
--- a/codex-rs/mcp-server/src/outgoing_message.rs
+++ b/codex-rs/mcp-server/src/outgoing_message.rs
@@ -258,12 +258,10 @@ pub(crate) struct OutgoingError {
 mod tests {
    use codex_core::protocol::EventMsg;
    use codex_core::protocol::SessionConfiguredEvent;
-    use codex_protocol::config_types::ReasoningEffort;
    use codex_protocol::mcp_protocol::ConversationId;
    use codex_protocol::mcp_protocol::LoginChatGptCompleteNotification;
    use pretty_assertions::assert_eq;
    use serde_json::json;
-    use tempfile::NamedTempFile;
    use uuid::Uuid;

    use super::*;
@@ -274,17 +272,14 @@ mod tests {
        let outgoing_message_sender = OutgoingMessageSender::new(outgoing_tx);

        let conversation_id = ConversationId::new();
-        let rollout_file = NamedTempFile::new().unwrap();
        let event = Event {
            id: "1".to_string(),
            msg: EventMsg::SessionConfigured(SessionConfiguredEvent {
                session_id: conversation_id,
                model: "gpt-4o".to_string(),
-                reasoning_effort: ReasoningEffort::default(),
                history_log_id: 1,
                history_entry_count: 1000,
                initial_messages: None,
-                rollout_path: rollout_file.path().to_path_buf(),
            }),
        };

@@ -301,7 +296,7 @@ mod tests {
        let Ok(expected_params) = serde_json::to_value(&event) else {
            panic!("Event must serialize");
        };
-        assert_eq!(params, Some(expected_params));
+        assert_eq!(params, Some(expected_params.clone()));
    }

    #[tokio::test]
@@ -310,15 +305,12 @@ mod tests {
        let outgoing_message_sender = OutgoingMessageSender::new(outgoing_tx);

        let conversation_id = ConversationId::new();
-        let rollout_file = NamedTempFile::new().unwrap();
        let session_configured_event = SessionConfiguredEvent {
            session_id: conversation_id,
            model: "gpt-4o".to_string(),
-            reasoning_effort: ReasoningEffort::default(),
            history_log_id: 1,
            history_entry_count: 1000,
            initial_messages: None,
-            rollout_path: rollout_file.path().to_path_buf(),
        };
        let event = Event {
            id: "1".to_string(),
@@ -345,11 +337,9 @@ mod tests {
            "msg": {
                "session_id": session_configured_event.session_id,
                "model": session_configured_event.model,
-                "reasoning_effort": session_configured_event.reasoning_effort,
                "history_log_id": session_configured_event.history_log_id,
                "history_entry_count": session_configured_event.history_entry_count,
                "type": "session_configured",
-                "rollout_path": rollout_file.path().to_path_buf(),
            }
        });
        assert_eq!(params.unwrap(), expected_params);
--- a/codex-rs/mcp-server/tests/common/Cargo.toml
+++ b/codex-rs/mcp-server/tests/common/Cargo.toml
@@ -9,11 +9,9 @@ path = "lib.rs"
 [dependencies]
 anyhow = "1"
 assert_cmd = "2"
-codex-core = { path = "../../../core" }
 codex-mcp-server = { path = "../.." }
 codex-protocol = { path = "../../../protocol" }
 mcp-types = { path = "../../../mcp-types" }
-os_info = "3.12.0"
 pretty_assertions = "1.4.1"
 serde = { version = "1" }
 serde_json = "1"
--- a/codex-rs/mcp-server/tests/common/mcp_process.rs
+++ b/codex-rs/mcp-server/tests/common/mcp_process.rs
@@ -13,18 +13,15 @@ use anyhow::Context;
 use assert_cmd::prelude::*;
 use codex_mcp_server::CodexToolCallParam;
 use codex_protocol::mcp_protocol::AddConversationListenerParams;
-use codex_protocol::mcp_protocol::ArchiveConversationParams;
 use codex_protocol::mcp_protocol::CancelLoginChatGptParams;
 use codex_protocol::mcp_protocol::GetAuthStatusParams;
 use codex_protocol::mcp_protocol::InterruptConversationParams;
 use codex_protocol::mcp_protocol::ListConversationsParams;
-use codex_protocol::mcp_protocol::LoginApiKeyParams;
 use codex_protocol::mcp_protocol::NewConversationParams;
 use codex_protocol::mcp_protocol::RemoveConversationListenerParams;
 use codex_protocol::mcp_protocol::ResumeConversationParams;
 use codex_protocol::mcp_protocol::SendUserMessageParams;
 use codex_protocol::mcp_protocol::SendUserTurnParams;
-use codex_protocol::mcp_protocol::SetDefaultModelParams;

 use mcp_types::CallToolRequestParams;
 use mcp_types::ClientCapabilities;
@@ -56,18 +53,6 @@ pub struct McpProcess {

 impl McpProcess {
    pub async fn new(codex_home: &Path) -> anyhow::Result<Self> {
-        Self::new_with_env(codex_home, &[]).await
-    }
-
-    /// Creates a new MCP process, allowing tests to override or remove
-    /// specific environment variables for the child process only.
-    ///
-    /// Pass a tuple of (key, Some(value)) to set/override, or (key, None) to
-    /// remove a variable from the child's environment.
-    pub async fn new_with_env(
-        codex_home: &Path,
-        env_overrides: &[(&str, Option<&str>)],
-    ) -> anyhow::Result<Self> {
        // Use assert_cmd to locate the binary path and then switch to tokio::process::Command
        let std_cmd = StdCommand::cargo_bin("codex-mcp-server")
            .context("should find binary for codex-mcp-server")?;
@@ -82,17 +67,6 @@ impl McpProcess {
        cmd.env("CODEX_HOME", codex_home);
        cmd.env("RUST_LOG", "debug");

-        for (k, v) in env_overrides {
-            match v {
-                Some(val) => {
-                    cmd.env(k, val);
-                }
-                None => {
-                    cmd.env_remove(k);
-                }
-            }
-        }
-
        let mut process = cmd
            .kill_on_drop(true)
            .spawn()
@@ -140,7 +114,6 @@ impl McpProcess {
                name: "elicitation test".into(),
                title: Some("Elicitation Test".into()),
                version: "0.0.0".into(),
-                user_agent: None,
            },
            protocol_version: mcp_types::MCP_SCHEMA_VERSION.into(),
        };
@@ -155,14 +128,6 @@ impl McpProcess {
        .await?;

        let initialized = self.read_jsonrpc_message().await?;
-        let os_info = os_info::get();
-        let user_agent = format!(
-            "codex_cli_rs/0.0.0 ({} {}; {}) {} (elicitation test; 0.0.0)",
-            os_info.os_type(),
-            os_info.version(),
-            os_info.architecture().unwrap_or("unknown"),
-            codex_core::terminal::user_agent()
-        );
        assert_eq!(
            JSONRPCMessage::Response(JSONRPCResponse {
                jsonrpc: JSONRPC_VERSION.into(),
@@ -176,8 +141,7 @@ impl McpProcess {
                    "serverInfo": {
                        "name": "codex-mcp-server",
                        "title": "Codex",
-                        "version": "0.0.0",
-                        "user_agent": user_agent
+                        "version": "0.0.0"
                    },
                    "protocolVersion": mcp_types::MCP_SCHEMA_VERSION
                })
@@ -222,15 +186,6 @@ impl McpProcess {
        self.send_request("newConversation", params).await
    }

-    /// Send an `archiveConversation` JSON-RPC request.
-    pub async fn send_archive_conversation_request(
-        &mut self,
-        params: ArchiveConversationParams,
-    ) -> anyhow::Result<i64> {
-        let params = Some(serde_json::to_value(params)?);
-        self.send_request("archiveConversation", params).await
-    }
-
    /// Send an `addConversationListener` JSON-RPC request.
    pub async fn send_add_conversation_listener_request(
        &mut self,
@@ -297,20 +252,6 @@ impl McpProcess {
        self.send_request("getUserAgent", None).await
    }

-    /// Send a `userInfo` JSON-RPC request.
-    pub async fn send_user_info_request(&mut self) -> anyhow::Result<i64> {
-        self.send_request("userInfo", None).await
-    }
-
-    /// Send a `setDefaultModel` JSON-RPC request.
-    pub async fn send_set_default_model_request(
-        &mut self,
-        params: SetDefaultModelParams,
-    ) -> anyhow::Result<i64> {
-        let params = Some(serde_json::to_value(params)?);
-        self.send_request("setDefaultModel", params).await
-    }
-
    /// Send a `listConversations` JSON-RPC request.
    pub async fn send_list_conversations_request(
        &mut self,
@@ -329,15 +270,6 @@ impl McpProcess {
        self.send_request("resumeConversation", params).await
    }

-    /// Send a `loginApiKey` JSON-RPC request.
-    pub async fn send_login_api_key_request(
-        &mut self,
-        params: LoginApiKeyParams,
-    ) -> anyhow::Result<i64> {
-        let params = Some(serde_json::to_value(params)?);
-        self.send_request("loginApiKey", params).await
-    }
-
    /// Send a `loginChatGpt` JSON-RPC request.
    pub async fn send_login_chat_gpt_request(&mut self) -> anyhow::Result<i64> {
        self.send_request("loginChatGpt", None).await
--- a/codex-rs/mcp-server/tests/suite/archive_conversation.rs
+++ b/codex-rs/mcp-server/tests/suite/archive_conversation.rs
@@ -1,105 +0,0 @@
-use std::path::Path;
-
-use codex_core::ARCHIVED_SESSIONS_SUBDIR;
-use codex_protocol::mcp_protocol::ArchiveConversationParams;
-use codex_protocol::mcp_protocol::ArchiveConversationResponse;
-use codex_protocol::mcp_protocol::NewConversationParams;
-use codex_protocol::mcp_protocol::NewConversationResponse;
-use mcp_test_support::McpProcess;
-use mcp_test_support::to_response;
-use mcp_types::JSONRPCResponse;
-use mcp_types::RequestId;
-use tempfile::TempDir;
-use tokio::time::timeout;
-
-const DEFAULT_READ_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(10);
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn archive_conversation_moves_rollout_into_archived_directory() {
-    let codex_home = TempDir::new().expect("create temp dir");
-    create_config_toml(codex_home.path()).expect("write config.toml");
-
-    let mut mcp = McpProcess::new(codex_home.path())
-        .await
-        .expect("spawn mcp process");
-    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize())
-        .await
-        .expect("initialize timeout")
-        .expect("initialize request");
-
-    let new_request_id = mcp
-        .send_new_conversation_request(NewConversationParams {
-            model: Some("mock-model".to_string()),
-            ..Default::default()
-        })
-        .await
-        .expect("send newConversation");
-    let new_response: JSONRPCResponse = timeout(
-        DEFAULT_READ_TIMEOUT,
-        mcp.read_stream_until_response_message(RequestId::Integer(new_request_id)),
-    )
-    .await
-    .expect("newConversation timeout")
-    .expect("newConversation response");
-
-    let NewConversationResponse {
-        conversation_id,
-        rollout_path,
-        ..
-    } = to_response::<NewConversationResponse>(new_response)
-        .expect("deserialize newConversation response");
-
-    assert!(
-        rollout_path.exists(),
-        "expected rollout path {} to exist",
-        rollout_path.display()
-    );
-
-    let archive_request_id = mcp
-        .send_archive_conversation_request(ArchiveConversationParams {
-            conversation_id,
-            rollout_path: rollout_path.clone(),
-        })
-        .await
-        .expect("send archiveConversation");
-    let archive_response: JSONRPCResponse = timeout(
-        DEFAULT_READ_TIMEOUT,
-        mcp.read_stream_until_response_message(RequestId::Integer(archive_request_id)),
-    )
-    .await
-    .expect("archiveConversation timeout")
-    .expect("archiveConversation response");
-
-    let _: ArchiveConversationResponse =
-        to_response::<ArchiveConversationResponse>(archive_response)
-            .expect("deserialize archiveConversation response");
-
-    let archived_directory = codex_home.path().join(ARCHIVED_SESSIONS_SUBDIR);
-    let archived_rollout_path =
-        archived_directory.join(rollout_path.file_name().unwrap_or_else(|| {
-            panic!("rollout path {} missing file name", rollout_path.display())
-        }));
-
-    assert!(
-        !rollout_path.exists(),
-        "expected rollout path {} to be moved",
-        rollout_path.display()
-    );
-    assert!(
-        archived_rollout_path.exists(),
-        "expected archived rollout path {} to exist",
-        archived_rollout_path.display()
-    );
-}
-
-fn create_config_toml(codex_home: &Path) -> std::io::Result<()> {
-    let config_toml = codex_home.join("config.toml");
-    std::fs::write(config_toml, config_contents())
-}
-
-fn config_contents() -> &'static str {
-    r#"model = "mock-model"
-approval_policy = "never"
-sandbox_mode = "read-only"
-"#
-}
--- a/codex-rs/mcp-server/tests/suite/auth.rs
+++ b/codex-rs/mcp-server/tests/suite/auth.rs
@@ -1,10 +1,9 @@
 use std::path::Path;

+use codex_core::auth::login_with_api_key;
 use codex_protocol::mcp_protocol::AuthMode;
 use codex_protocol::mcp_protocol::GetAuthStatusParams;
 use codex_protocol::mcp_protocol::GetAuthStatusResponse;
-use codex_protocol::mcp_protocol::LoginApiKeyParams;
-use codex_protocol::mcp_protocol::LoginApiKeyResponse;
 use mcp_test_support::McpProcess;
 use mcp_test_support::to_response;
 use mcp_types::JSONRPCResponse;
@@ -37,31 +36,12 @@ stream_max_retries = 0
    )
 }

-async fn login_with_api_key_via_request(mcp: &mut McpProcess, api_key: &str) {
-    let request_id = mcp
-        .send_login_api_key_request(LoginApiKeyParams {
-            api_key: api_key.to_string(),
-        })
-        .await
-        .unwrap_or_else(|e| panic!("send loginApiKey: {e}"));
-
-    let resp: JSONRPCResponse = timeout(
-        DEFAULT_READ_TIMEOUT,
-        mcp.read_stream_until_response_message(RequestId::Integer(request_id)),
-    )
-    .await
-    .unwrap_or_else(|e| panic!("loginApiKey timeout: {e}"))
-    .unwrap_or_else(|e| panic!("loginApiKey response: {e}"));
-    let _: LoginApiKeyResponse =
-        to_response(resp).unwrap_or_else(|e| panic!("deserialize login response: {e}"));
-}
-
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn get_auth_status_no_auth() {
    let codex_home = TempDir::new().unwrap_or_else(|e| panic!("create tempdir: {e}"));
-    create_config_toml(codex_home.path()).unwrap_or_else(|err| panic!("write config.toml: {err}"));
+    create_config_toml(codex_home.path()).expect("write config.toml");

-    let mut mcp = McpProcess::new_with_env(codex_home.path(), &[("OPENAI_API_KEY", None)])
+    let mut mcp = McpProcess::new(codex_home.path())
        .await
        .expect("spawn mcp process");
    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize())
@@ -92,7 +72,8 @@ async fn get_auth_status_no_auth() {
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn get_auth_status_with_api_key() {
    let codex_home = TempDir::new().unwrap_or_else(|e| panic!("create tempdir: {e}"));
-    create_config_toml(codex_home.path()).unwrap_or_else(|err| panic!("write config.toml: {err}"));
+    create_config_toml(codex_home.path()).expect("write config.toml");
+    login_with_api_key(codex_home.path(), "sk-test-key").expect("seed api key");

    let mut mcp = McpProcess::new(codex_home.path())
        .await
@@ -102,8 +83,6 @@ async fn get_auth_status_with_api_key() {
        .expect("init timeout")
        .expect("init failed");

-    login_with_api_key_via_request(&mut mcp, "sk-test-key").await;
-
    let request_id = mcp
        .send_get_auth_status_request(GetAuthStatusParams {
            include_token: Some(true),
@@ -122,12 +101,14 @@ async fn get_auth_status_with_api_key() {
    let status: GetAuthStatusResponse = to_response(resp).expect("deserialize status");
    assert_eq!(status.auth_method, Some(AuthMode::ApiKey));
    assert_eq!(status.auth_token, Some("sk-test-key".to_string()));
+    assert_eq!(status.preferred_auth_method, AuthMode::ChatGPT);
 }

 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn get_auth_status_with_api_key_no_include_token() {
    let codex_home = TempDir::new().unwrap_or_else(|e| panic!("create tempdir: {e}"));
-    create_config_toml(codex_home.path()).unwrap_or_else(|err| panic!("write config.toml: {err}"));
+    create_config_toml(codex_home.path()).expect("write config.toml");
+    login_with_api_key(codex_home.path(), "sk-test-key").expect("seed api key");

    let mut mcp = McpProcess::new(codex_home.path())
        .await
@@ -137,8 +118,6 @@ async fn get_auth_status_with_api_key_no_include_token() {
        .expect("init timeout")
        .expect("init failed");

-    login_with_api_key_via_request(&mut mcp, "sk-test-key").await;
-
    // Build params via struct so None field is omitted in wire JSON.
    let params = GetAuthStatusParams {
        include_token: None,
@@ -159,4 +138,5 @@ async fn get_auth_status_with_api_key_no_include_token() {
    let status: GetAuthStatusResponse = to_response(resp).expect("deserialize status");
    assert_eq!(status.auth_method, Some(AuthMode::ApiKey));
    assert!(status.auth_token.is_none(), "token must be omitted");
+    assert_eq!(status.preferred_auth_method, AuthMode::ChatGPT);
 }
--- a/codex-rs/mcp-server/tests/suite/codex_message_processor_flow.rs
+++ b/codex-rs/mcp-server/tests/suite/codex_message_processor_flow.rs
@@ -90,8 +90,6 @@ async fn test_codex_jsonrpc_conversation_flow() {
    let NewConversationResponse {
        conversation_id,
        model,
-        reasoning_effort: _,
-        rollout_path: _,
    } = new_conv_resp;
    assert_eq!(model, "mock-model");

--- a/codex-rs/mcp-server/tests/suite/create_conversation.rs
+++ b/codex-rs/mcp-server/tests/suite/create_conversation.rs
@@ -59,8 +59,6 @@ async fn test_conversation_create_and_send_message_ok() {
    let NewConversationResponse {
        conversation_id,
        model,
-        reasoning_effort: _,
-        rollout_path: _,
    } = to_response::<NewConversationResponse>(new_conv_resp)
        .expect("deserialize newConversation response");
    assert_eq!(model, "o3");
--- a/codex-rs/mcp-server/tests/suite/list_resume.rs
+++ b/codex-rs/mcp-server/tests/suite/list_resume.rs
@@ -156,45 +156,14 @@ fn create_fake_rollout(codex_home: &Path, filename_ts: &str, meta_rfc3339: &str,

    let file_path = dir.join(format!("rollout-{filename_ts}-{uuid}.jsonl"));
    let mut lines = Vec::new();
-    // Meta line with timestamp (flattened meta in payload for new schema)
+    // Meta line with timestamp
+    lines.push(json!({"timestamp": meta_rfc3339, "id": uuid}).to_string());
+    // Minimal user message entry as a persisted response item
    lines.push(
        json!({
-            "timestamp": meta_rfc3339,
-            "type": "session_meta",
-            "payload": {
-                "id": uuid,
-                "timestamp": meta_rfc3339,
-                "cwd": "/",
-                "originator": "codex",
-                "cli_version": "0.0.0",
-                "instructions": null
-            }
-        })
-        .to_string(),
-    );
-    // Minimal user message entry as a persisted response item (with envelope timestamp)
-    lines.push(
-        json!({
-            "timestamp": meta_rfc3339,
-            "type":"response_item",
-            "payload": {
-                "type":"message",
-                "role":"user",
-                "content":[{"type":"input_text","text": preview}]
-            }
-        })
-        .to_string(),
-    );
-    // Add a matching user message event line to satisfy filters
-    lines.push(
-        json!({
-            "timestamp": meta_rfc3339,
-            "type":"event_msg",
-            "payload": {
-                "type":"user_message",
-                "message": preview,
-                "kind": "plain"
-            }
+            "type":"message",
+            "role":"user",
+            "content":[{"type":"input_text","text": preview}]
        })
        .to_string(),
    );
--- a/codex-rs/mcp-server/tests/suite/login.rs
+++ b/codex-rs/mcp-server/tests/suite/login.rs
@@ -1,7 +1,7 @@
 use std::path::Path;
 use std::time::Duration;

-use codex_login::login_with_api_key;
+use codex_core::auth::login_with_api_key;
 use codex_protocol::mcp_protocol::CancelLoginChatGptParams;
 use codex_protocol::mcp_protocol::CancelLoginChatGptResponse;
 use codex_protocol::mcp_protocol::GetAuthStatusParams;
@@ -46,7 +46,7 @@ async fn logout_chatgpt_removes_auth() {
    login_with_api_key(codex_home.path(), "sk-test-key").expect("seed api key");
    assert!(codex_home.path().join("auth.json").exists());

-    let mut mcp = McpProcess::new_with_env(codex_home.path(), &[("OPENAI_API_KEY", None)])
+    let mut mcp = McpProcess::new(codex_home.path())
        .await
        .expect("spawn mcp process");
    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize())
@@ -95,7 +95,7 @@ async fn logout_chatgpt_removes_auth() {
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn login_and_cancel_chatgpt() {
    let codex_home = TempDir::new().unwrap_or_else(|e| panic!("create tempdir: {e}"));
-    create_config_toml(codex_home.path()).unwrap_or_else(|err| panic!("write config.toml: {err}"));
+    create_config_toml(codex_home.path()).expect("write config.toml");

    let mut mcp = McpProcess::new(codex_home.path())
        .await
--- a/codex-rs/mcp-server/tests/suite/mod.rs
+++ b/codex-rs/mcp-server/tests/suite/mod.rs
@@ -1,5 +1,4 @@
 // Aggregates all former standalone integration tests as modules.
-mod archive_conversation;
 mod auth;
 mod codex_message_processor_flow;
 mod codex_tool;
@@ -9,6 +8,4 @@ mod interrupt;
 mod list_resume;
 mod login;
 mod send_message;
-mod set_default_model;
 mod user_agent;
-mod user_info;
--- a/codex-rs/mcp-server/tests/suite/set_default_model.rs
+++ b/codex-rs/mcp-server/tests/suite/set_default_model.rs
@@ -1,62 +0,0 @@
-use codex_core::config::ConfigToml;
-use codex_protocol::config_types::ReasoningEffort;
-use codex_protocol::mcp_protocol::SetDefaultModelParams;
-use codex_protocol::mcp_protocol::SetDefaultModelResponse;
-use mcp_test_support::McpProcess;
-use mcp_test_support::to_response;
-use mcp_types::JSONRPCResponse;
-use mcp_types::RequestId;
-use pretty_assertions::assert_eq;
-use tempfile::TempDir;
-use tokio::time::timeout;
-
-const DEFAULT_READ_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(10);
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn set_default_model_persists_overrides() {
-    let codex_home = TempDir::new().unwrap_or_else(|e| panic!("create tempdir: {e}"));
-
-    let mut mcp = McpProcess::new(codex_home.path())
-        .await
-        .expect("spawn mcp process");
-    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize())
-        .await
-        .expect("init timeout")
-        .expect("init failed");
-
-    let params = SetDefaultModelParams {
-        model: Some("o4-mini".to_string()),
-        reasoning_effort: Some(ReasoningEffort::High),
-    };
-
-    let request_id = mcp
-        .send_set_default_model_request(params)
-        .await
-        .expect("send setDefaultModel");
-
-    let resp: JSONRPCResponse = timeout(
-        DEFAULT_READ_TIMEOUT,
-        mcp.read_stream_until_response_message(RequestId::Integer(request_id)),
-    )
-    .await
-    .expect("setDefaultModel timeout")
-    .expect("setDefaultModel response");
-
-    let _: SetDefaultModelResponse =
-        to_response(resp).expect("deserialize setDefaultModel response");
-
-    let config_path = codex_home.path().join("config.toml");
-    let config_contents = tokio::fs::read_to_string(&config_path)
-        .await
-        .expect("read config.toml");
-    let config_toml: ConfigToml = toml::from_str(&config_contents).expect("parse config.toml");
-
-    assert_eq!(
-        ConfigToml {
-            model: Some("o4-mini".to_string()),
-            model_reasoning_effort: Some(ReasoningEffort::High),
-            ..Default::default()
-        },
-        config_toml,
-    );
-}
--- a/codex-rs/mcp-server/tests/suite/user_agent.rs
+++ b/codex-rs/mcp-server/tests/suite/user_agent.rs
@@ -1,3 +1,5 @@
+use codex_core::default_client::DEFAULT_ORIGINATOR;
+use codex_core::default_client::get_codex_user_agent;
 use codex_protocol::mcp_protocol::GetUserAgentResponse;
 use mcp_test_support::McpProcess;
 use mcp_test_support::to_response;
@@ -33,18 +35,11 @@ async fn get_user_agent_returns_current_codex_user_agent() {
    .expect("getUserAgent timeout")
    .expect("getUserAgent response");

-    let os_info = os_info::get();
-    let user_agent = format!(
-        "codex_cli_rs/0.0.0 ({} {}; {}) {} (elicitation test; 0.0.0)",
-        os_info.os_type(),
-        os_info.version(),
-        os_info.architecture().unwrap_or("unknown"),
-        codex_core::terminal::user_agent()
-    );
-
    let received: GetUserAgentResponse =
        to_response(response).expect("deserialize getUserAgent response");
-    let expected = GetUserAgentResponse { user_agent };
+    let expected = GetUserAgentResponse {
+        user_agent: get_codex_user_agent(Some(DEFAULT_ORIGINATOR)),
+    };

    assert_eq!(received, expected);
 }
--- a/codex-rs/mcp-server/tests/suite/user_info.rs
+++ b/codex-rs/mcp-server/tests/suite/user_info.rs
@@ -1,78 +0,0 @@
-use std::time::Duration;
-
-use anyhow::Context;
-use base64::Engine;
-use base64::engine::general_purpose::URL_SAFE_NO_PAD;
-use codex_core::auth::AuthDotJson;
-use codex_core::auth::get_auth_file;
-use codex_core::auth::write_auth_json;
-use codex_core::token_data::IdTokenInfo;
-use codex_core::token_data::TokenData;
-use codex_protocol::mcp_protocol::UserInfoResponse;
-use mcp_test_support::McpProcess;
-use mcp_test_support::to_response;
-use mcp_types::JSONRPCResponse;
-use mcp_types::RequestId;
-use pretty_assertions::assert_eq;
-use serde_json::json;
-use tempfile::TempDir;
-use tokio::time::timeout;
-
-const DEFAULT_READ_TIMEOUT: Duration = Duration::from_secs(10);
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn user_info_returns_email_from_auth_json() {
-    let codex_home = TempDir::new().expect("create tempdir");
-
-    let auth_path = get_auth_file(codex_home.path());
-    let mut id_token = IdTokenInfo::default();
-    id_token.email = Some("user@example.com".to_string());
-    id_token.raw_jwt = encode_id_token_with_email("user@example.com").expect("encode id token");
-
-    let auth = AuthDotJson {
-        openai_api_key: None,
-        tokens: Some(TokenData {
-            id_token,
-            access_token: "access".to_string(),
-            refresh_token: "refresh".to_string(),
-            account_id: None,
-        }),
-        last_refresh: None,
-    };
-    write_auth_json(&auth_path, &auth).expect("write auth.json");
-
-    let mut mcp = McpProcess::new(codex_home.path())
-        .await
-        .expect("spawn mcp process");
-    timeout(DEFAULT_READ_TIMEOUT, mcp.initialize())
-        .await
-        .expect("initialize timeout")
-        .expect("initialize request");
-
-    let request_id = mcp.send_user_info_request().await.expect("send userInfo");
-    let response: JSONRPCResponse = timeout(
-        DEFAULT_READ_TIMEOUT,
-        mcp.read_stream_until_response_message(RequestId::Integer(request_id)),
-    )
-    .await
-    .expect("userInfo timeout")
-    .expect("userInfo response");
-
-    let received: UserInfoResponse = to_response(response).expect("deserialize userInfo response");
-    let expected = UserInfoResponse {
-        alleged_user_email: Some("user@example.com".to_string()),
-    };
-
-    assert_eq!(received, expected);
-}
-
-fn encode_id_token_with_email(email: &str) -> anyhow::Result<String> {
-    let header_b64 = URL_SAFE_NO_PAD.encode(
-        serde_json::to_vec(&json!({ "alg": "none", "typ": "JWT" }))
-            .context("serialize jwt header")?,
-    );
-    let payload =
-        serde_json::to_vec(&json!({ "email": email })).context("serialize jwt payload")?;
-    let payload_b64 = URL_SAFE_NO_PAD.encode(payload);
-    Ok(format!("{header_b64}.{payload_b64}.signature"))
-}
--- a/codex-rs/mcp-types/check_lib_rs.py
+++ b/codex-rs/mcp-types/check_lib_rs.py
@@ -1,21 +0,0 @@
-#!/usr/bin/env python3
-
-import subprocess
-import sys
-from pathlib import Path
-
-
-def main() -> int:
-    crate_dir = Path(__file__).resolve().parent
-    generator = crate_dir / "generate_mcp_types.py"
-
-    result = subprocess.run(
-        [sys.executable, str(generator), "--check"],
-        cwd=crate_dir,
-        check=False,
-    )
-    return result.returncode
-
-
-if __name__ == "__main__":
-    raise SystemExit(main())
--- a/codex-rs/mcp-types/generate_mcp_types.py
+++ b/codex-rs/mcp-types/generate_mcp_types.py
@@ -5,19 +5,15 @@ import argparse
 import json
 import subprocess
 import sys
-import tempfile

 from dataclasses import (
    dataclass,
 )
-from difflib import unified_diff
 from pathlib import Path
-from shutil import copy2

 # Helper first so it is defined when other functions call it.
 from typing import Any, Literal

-
 SCHEMA_VERSION = "2025-06-18"
 JSONRPC_VERSION = "2.0"

@@ -47,31 +43,16 @@ def main() -> int:
    default_schema_file = (
        Path(__file__).resolve().parent / "schema" / SCHEMA_VERSION / "schema.json"
    )
-    default_lib_rs = Path(__file__).resolve().parent / "src/lib.rs"
    parser.add_argument(
        "schema_file",
        nargs="?",
        default=default_schema_file,
        help="schema.json file to process",
    )
-    parser.add_argument(
-        "--check",
-        action="store_true",
-        help="Regenerate lib.rs in a sandbox and ensure the checked-in file matches",
-    )
    args = parser.parse_args()
-    schema_file = Path(args.schema_file)
-    crate_dir = Path(__file__).resolve().parent
+    schema_file = args.schema_file

-    if args.check:
-        return run_check(schema_file, crate_dir, default_lib_rs)
-
-    generate_lib_rs(schema_file, default_lib_rs, fmt=True)
-    return 0
-
-
-def generate_lib_rs(schema_file: Path, lib_rs: Path, fmt: bool) -> None:
-    lib_rs.parent.mkdir(parents=True, exist_ok=True)
+    lib_rs = Path(__file__).resolve().parent / "src/lib.rs"

    global DEFINITIONS  # Allow helper functions to access the schema.

@@ -136,7 +117,9 @@ fn default_jsonrpc() -> String {{ JSONRPC_VERSION.to_owned() }}

    for req_name in CLIENT_REQUEST_TYPE_NAMES:
        defn = definitions[req_name]
-        method_const = defn.get("properties", {}).get("method", {}).get("const", req_name)
+        method_const = (
+            defn.get("properties", {}).get("method", {}).get("const", req_name)
+        )
        payload_type = f"<{req_name} as ModelContextProtocolRequest>::Params"
        try_from_impl_lines.append(f'            "{method_const}" => {{\n')
        try_from_impl_lines.append(
@@ -145,7 +128,9 @@ fn default_jsonrpc() -> String {{ JSONRPC_VERSION.to_owned() }}
        try_from_impl_lines.append(
            f"                let params: {payload_type} = serde_json::from_value(params_json)?;\n"
        )
-        try_from_impl_lines.append(f"                Ok(ClientRequest::{req_name}(params))\n")
+        try_from_impl_lines.append(
+            f"                Ok(ClientRequest::{req_name}(params))\n"
+        )
        try_from_impl_lines.append("            },\n")

    try_from_impl_lines.append(
@@ -159,7 +144,9 @@ fn default_jsonrpc() -> String {{ JSONRPC_VERSION.to_owned() }}

    # Generate TryFrom for ServerNotification
    notif_impl_lines: list[str] = []
-    notif_impl_lines.append("impl TryFrom<JSONRPCNotification> for ServerNotification {\n")
+    notif_impl_lines.append(
+        "impl TryFrom<JSONRPCNotification> for ServerNotification {\n"
+    )
    notif_impl_lines.append("    type Error = serde_json::Error;\n")
    notif_impl_lines.append(
        "    fn try_from(n: JSONRPCNotification) -> std::result::Result<Self, Self::Error> {\n"
@@ -168,7 +155,9 @@ fn default_jsonrpc() -> String {{ JSONRPC_VERSION.to_owned() }}

    for notif_name in SERVER_NOTIFICATION_TYPE_NAMES:
        n_def = definitions[notif_name]
-        method_const = n_def.get("properties", {}).get("method", {}).get("const", notif_name)
+        method_const = (
+            n_def.get("properties", {}).get("method", {}).get("const", notif_name)
+        )
        payload_type = f"<{notif_name} as ModelContextProtocolNotification>::Params"
        notif_impl_lines.append(f'            "{method_const}" => {{\n')
        # params may be optional
@@ -178,7 +167,9 @@ fn default_jsonrpc() -> String {{ JSONRPC_VERSION.to_owned() }}
        notif_impl_lines.append(
            f"                let params: {payload_type} = serde_json::from_value(params_json)?;\n"
        )
-        notif_impl_lines.append(f"                Ok(ServerNotification::{notif_name}(params))\n")
+        notif_impl_lines.append(
+            f"                Ok(ServerNotification::{notif_name}(params))\n"
+        )
        notif_impl_lines.append("            },\n")

    notif_impl_lines.append(
@@ -194,70 +185,13 @@ fn default_jsonrpc() -> String {{ JSONRPC_VERSION.to_owned() }}
        for chunk in out:
            f.write(chunk)

-    if fmt:
-        subprocess.check_call(
-            ["cargo", "fmt", "--", "--config", "imports_granularity=Item"],
-            cwd=lib_rs.parent.parent,
-            stderr=subprocess.DEVNULL,
-        )
+    subprocess.check_call(
+        ["cargo", "fmt", "--", "--config", "imports_granularity=Item"],
+        cwd=lib_rs.parent.parent,
+        stderr=subprocess.DEVNULL,
+    )

-
-def run_check(schema_file: Path, crate_dir: Path, checked_in_lib: Path) -> int:
-    config_path = crate_dir.parent / "rustfmt.toml"
-    eprint(f"Running --check with schema {schema_file}")
-
-    with tempfile.TemporaryDirectory() as tmp_dir:
-        tmp_path = Path(tmp_dir)
-        eprint(f"Created temporary workspace at {tmp_path}")
-        manifest_path = tmp_path / "Cargo.toml"
-        eprint(f"Copying Cargo.toml into {manifest_path}")
-        copy2(crate_dir / "Cargo.toml", manifest_path)
-        manifest_text = manifest_path.read_text(encoding="utf-8")
-        manifest_text = manifest_text.replace(
-            "version = { workspace = true }",
-            'version = "0.0.0"',
-        )
-        manifest_text = manifest_text.replace("\n[lints]\nworkspace = true\n", "\n")
-        manifest_path.write_text(manifest_text, encoding="utf-8")
-        src_dir = tmp_path / "src"
-        src_dir.mkdir(parents=True, exist_ok=True)
-        eprint(f"Generating lib.rs into {src_dir}")
-        generated_lib = src_dir / "lib.rs"
-
-        generate_lib_rs(schema_file, generated_lib, fmt=False)
-
-        eprint("Formatting generated lib.rs with rustfmt")
-        subprocess.check_call(
-            [
-                "rustfmt",
-                "--config-path",
-                str(config_path),
-                str(generated_lib),
-            ],
-            cwd=tmp_path,
-            stderr=subprocess.DEVNULL,
-        )
-
-        eprint("Comparing generated lib.rs with checked-in version")
-        checked_in_contents = checked_in_lib.read_text(encoding="utf-8")
-        generated_contents = generated_lib.read_text(encoding="utf-8")
-
-        if checked_in_contents == generated_contents:
-            eprint("lib.rs matches checked-in version")
-            return 0
-
-        diff = unified_diff(
-            checked_in_contents.splitlines(keepends=True),
-            generated_contents.splitlines(keepends=True),
-            fromfile=str(checked_in_lib),
-            tofile=str(generated_lib),
-        )
-        diff_text = "".join(diff)
-        eprint("Generated lib.rs does not match the checked-in version. Diff:")
-        if diff_text:
-            eprint(diff_text, end="")
-        eprint("Re-run generate_mcp_types.py without --check to update src/lib.rs.")
-        return 1
+    return 0


 def add_definition(name: str, definition: dict[str, Any], out: list[str]) -> None:
@@ -331,11 +265,8 @@ class StructField:
    name: str
    type_name: str
    serde: str | None = None
-    comment: str | None = None

    def append(self, out: list[str], supports_const: bool) -> None:
-        if self.comment:
-            out.append(f"    // {self.comment}\n")
        if self.serde:
            out.append(f"    {self.serde}\n")
        if self.viz == "const":
@@ -381,18 +312,6 @@ def define_struct(
        else:
            fields.append(StructField("pub", rs_prop.name, prop_type, rs_prop.serde))

-    # Special-case: add Codex-specific user_agent to Implementation
-    if name == "Implementation":
-        fields.append(
-            StructField(
-                "pub",
-                "user_agent",
-                "Option<String>",
-                '#[serde(default, skip_serializing_if = "Option::is_none")]',
-                "This is an extra field that the Codex MCP server sends as part of InitializeResult.",
-            )
-        )
-
    if implements_request_trait(name):
        add_trait_impl(name, "ModelContextProtocolRequest", fields, out)
    elif implements_notification_trait(name):
@@ -487,11 +406,15 @@ def define_untagged_enum(name: str, type_list: list[str], out: list[str]) -> Non
            case "integer":
                out.append("    Integer(i64),\n")
            case _:
-                raise ValueError(f"Unknown type in untagged enum: {simple_type} in {name}")
+                raise ValueError(
+                    f"Unknown type in untagged enum: {simple_type} in {name}"
+                )
    out.append("}\n\n")


-def define_any_of(name: str, list_of_refs: list[Any], description: str | None = None) -> list[str]:
+def define_any_of(
+    name: str, list_of_refs: list[Any], description: str | None = None
+) -> list[str]:
    """Generate a Rust enum for a JSON-Schema `anyOf` union.

    For most types we simply map each `$ref` inside the `anyOf` list to a
@@ -556,7 +479,9 @@ def define_any_of(name: str, list_of_refs: list[Any], description: str | None =
            if name == "ClientRequest":
                payload_type = f"<{ref_name} as ModelContextProtocolRequest>::Params"
            else:
-                payload_type = f"<{ref_name} as ModelContextProtocolNotification>::Params"
+                payload_type = (
+                    f"<{ref_name} as ModelContextProtocolNotification>::Params"
+                )

            # Determine the wire value for `method` so we can annotate the
            # variant appropriately. If for some reason the schema does not
@@ -564,7 +489,9 @@ def define_any_of(name: str, list_of_refs: list[Any], description: str | None =
            # least compile (although deserialization will likely fail).
            request_def = DEFINITIONS.get(ref_name, {})
            method_const = (
-                request_def.get("properties", {}).get("method", {}).get("const", ref_name)
+                request_def.get("properties", {})
+                .get("method", {})
+                .get("const", ref_name)
            )

            out.append(f'    #[serde(rename = "{method_const}")]\n')
@@ -614,7 +541,7 @@ def map_type(
    if type_prop == "string":
        if const_prop := typedef.get("const", None):
            assert isinstance(const_prop, str)
-            return f'&\'static str = "{const_prop}"'
+            return f'&\'static str = "{const_prop    }"'
        else:
            return "String"
    elif type_prop == "integer":
@@ -690,7 +617,7 @@ def rust_prop_name(name: str, is_optional: bool) -> RustProp:
        serde_annotations.append('skip_serializing_if = "Option::is_none"')

    if serde_annotations:
-        serde_str = f"#[serde({', '.join(serde_annotations)})]"
+        serde_str = f'#[serde({", ".join(serde_annotations)})]'
    else:
        serde_str = None
    return RustProp(prop_name, serde_str)
@@ -698,7 +625,9 @@ def rust_prop_name(name: str, is_optional: bool) -> RustProp:

 def to_snake_case(name: str) -> str:
    """Convert a camelCase or PascalCase name to snake_case."""
-    snake_case = name[0].lower() + "".join("_" + c.lower() if c.isupper() else c for c in name[1:])
+    snake_case = name[0].lower() + "".join(
+        "_" + c.lower() if c.isupper() else c for c in name[1:]
+    )
    if snake_case != name:
        return snake_case
    else:
@@ -734,9 +663,5 @@ def emit_doc_comment(text: str | None, out: list[str]) -> None:
        out.append(f"/// {line.rstrip()}\n")


-def eprint(*args: Any, **kwargs: Any) -> None:
-    print(*args, file=sys.stderr, **kwargs)
-
-
 if __name__ == "__main__":
    sys.exit(main())
--- a/codex-rs/mcp-types/src/lib.rs
+++ b/codex-rs/mcp-types/src/lib.rs
@@ -487,9 +487,6 @@ pub struct Implementation {
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub title: Option<String>,
    pub version: String,
-    // This is an extra field that the Codex MCP server sends as part of InitializeResult.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub user_agent: Option<String>,
 }

 #[derive(Debug, Clone, PartialEq, Deserialize, Serialize, TS)]
--- a/codex-rs/mcp-types/tests/suite/initialize.rs
+++ b/codex-rs/mcp-types/tests/suite/initialize.rs
@@ -62,7 +62,6 @@ fn deserialize_initialize_request() {
                name: "acme-client".into(),
                title: Some("Acme".to_string()),
                version: "1.2.3".into(),
-                user_agent: None,
            },
            protocol_version: "2025-06-18".into(),
        }
--- a/codex-rs/protocol-ts/Cargo.toml
+++ b/codex-rs/protocol-ts/Cargo.toml
@@ -16,7 +16,6 @@ path = "src/main.rs"

 [dependencies]
 anyhow = "1"
-mcp-types = { path = "../mcp-types" }
 codex-protocol = { path = "../protocol" }
 ts-rs = "11"
 clap = { version = "4", features = ["derive"] }
--- a/codex-rs/protocol-ts/src/lib.rs
+++ b/codex-rs/protocol-ts/src/lib.rs
@@ -16,37 +16,29 @@ pub fn generate_ts(out_dir: &Path, prettier: Option<&Path>) -> Result<()> {
    ensure_dir(out_dir)?;

    // Generate TS bindings
-    mcp_types::InitializeResult::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::ConversationId::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::InputItem::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::ClientRequest::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::ServerRequest::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::NewConversationResponse::export_all_to(out_dir)?;
-    codex_protocol::mcp_protocol::ListConversationsResponse::export_all_to(out_dir)?;
-    codex_protocol::mcp_protocol::ResumeConversationResponse::export_all_to(out_dir)?;
-    codex_protocol::mcp_protocol::ArchiveConversationResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::AddConversationSubscriptionResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::RemoveConversationSubscriptionResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::SendUserMessageResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::SendUserTurnResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::InterruptConversationResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::GitDiffToRemoteResponse::export_all_to(out_dir)?;
-    codex_protocol::mcp_protocol::LoginApiKeyParams::export_all_to(out_dir)?;
-    codex_protocol::mcp_protocol::LoginApiKeyResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::LoginChatGptResponse::export_all_to(out_dir)?;
+    codex_protocol::mcp_protocol::LoginChatGptCompleteNotification::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::CancelLoginChatGptResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::LogoutChatGptResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::GetAuthStatusResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::ApplyPatchApprovalResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::ExecCommandApprovalResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::GetUserSavedConfigResponse::export_all_to(out_dir)?;
-    codex_protocol::mcp_protocol::SetDefaultModelResponse::export_all_to(out_dir)?;
    codex_protocol::mcp_protocol::GetUserAgentResponse::export_all_to(out_dir)?;
-    codex_protocol::mcp_protocol::UserInfoResponse::export_all_to(out_dir)?;
-
-    // All notification types reachable from this enum will be generated by
-    // induction, so they do not need to be listed individually.
    codex_protocol::mcp_protocol::ServerNotification::export_all_to(out_dir)?;
+    codex_protocol::mcp_protocol::ListConversationsResponse::export_all_to(out_dir)?;
+    codex_protocol::mcp_protocol::ResumeConversationResponse::export_all_to(out_dir)?;

    generate_index_ts(out_dir)?;

--- a/codex-rs/protocol/Cargo.toml
+++ b/codex-rs/protocol/Cargo.toml
@@ -28,7 +28,6 @@ uuid = { version = "1", features = ["serde", "v4"] }

 [dev-dependencies]
 pretty_assertions = "1.4.1"
-tempfile = "3"

 [package.metadata.cargo-shear]
 # Required because the not imported as strum_macros in non-nightly builds.
--- a/codex-rs/protocol/src/mcp_protocol.rs
+++ b/codex-rs/protocol/src/mcp_protocol.rs
@@ -91,11 +91,6 @@ pub enum ClientRequest {
        request_id: RequestId,
        params: ResumeConversationParams,
    },
-    ArchiveConversation {
-        #[serde(rename = "id")]
-        request_id: RequestId,
-        params: ArchiveConversationParams,
-    },
    SendUserMessage {
        #[serde(rename = "id")]
        request_id: RequestId,
@@ -126,11 +121,6 @@ pub enum ClientRequest {
        request_id: RequestId,
        params: GitDiffToRemoteParams,
    },
-    LoginApiKey {
-        #[serde(rename = "id")]
-        request_id: RequestId,
-        params: LoginApiKeyParams,
-    },
    LoginChatGpt {
        #[serde(rename = "id")]
        request_id: RequestId,
@@ -153,19 +143,10 @@ pub enum ClientRequest {
        #[serde(rename = "id")]
        request_id: RequestId,
    },
-    SetDefaultModel {
-        #[serde(rename = "id")]
-        request_id: RequestId,
-        params: SetDefaultModelParams,
-    },
    GetUserAgent {
        #[serde(rename = "id")]
        request_id: RequestId,
    },
-    UserInfo {
-        #[serde(rename = "id")]
-        request_id: RequestId,
-    },
    /// Execute a command (argv vector) under the server's sandbox.
    ExecOneOffCommand {
        #[serde(rename = "id")]
@@ -222,9 +203,6 @@ pub struct NewConversationParams {
 pub struct NewConversationResponse {
    pub conversation_id: ConversationId,
    pub model: String,
-    /// Note this could be ignored by the model.
-    pub reasoning_effort: ReasoningEffort,
-    pub rollout_path: PathBuf,
 }

 #[derive(Serialize, Deserialize, Debug, Clone, TS)]
@@ -284,32 +262,10 @@ pub struct AddConversationSubscriptionResponse {
    pub subscription_id: Uuid,
 }

-/// The [`ConversationId`] must match the `rollout_path`.
-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
-#[serde(rename_all = "camelCase")]
-pub struct ArchiveConversationParams {
-    pub conversation_id: ConversationId,
-    pub rollout_path: PathBuf,
-}
-
-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
-#[serde(rename_all = "camelCase")]
-pub struct ArchiveConversationResponse {}
-
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
 #[serde(rename_all = "camelCase")]
 pub struct RemoveConversationSubscriptionResponse {}

-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
-#[serde(rename_all = "camelCase")]
-pub struct LoginApiKeyParams {
-    pub api_key: String,
-}
-
-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
-#[serde(rename_all = "camelCase")]
-pub struct LoginApiKeyResponse {}
-
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
 #[serde(rename_all = "camelCase")]
 pub struct LoginChatGptResponse {
@@ -389,14 +345,9 @@ pub struct ExecArbitraryCommandResponse {
 pub struct GetAuthStatusResponse {
    #[serde(skip_serializing_if = "Option::is_none")]
    pub auth_method: Option<AuthMode>,
+    pub preferred_auth_method: AuthMode,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub auth_token: Option<String>,
-
-    // Indicates that auth method must be valid to use the server.
-    // This can be false if using a custom provider that is configured
-    // with requires_openai_auth == false.
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub requires_openai_auth: Option<bool>,
 }

 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
@@ -405,35 +356,12 @@ pub struct GetUserAgentResponse {
    pub user_agent: String,
 }

-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
-#[serde(rename_all = "camelCase")]
-pub struct UserInfoResponse {
-    /// Note: `alleged_user_email` is not currently verified. We read it from
-    /// the local auth.json, which the user could theoretically modify. In the
-    /// future, we may add logic to verify the email against the server before
-    /// returning it.
-    pub alleged_user_email: Option<String>,
-}
-
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
 #[serde(rename_all = "camelCase")]
 pub struct GetUserSavedConfigResponse {
    pub config: UserSavedConfig,
 }

-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
-#[serde(rename_all = "camelCase")]
-pub struct SetDefaultModelParams {
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub model: Option<String>,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub reasoning_effort: Option<ReasoningEffort>,
-}
-
-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, TS)]
-#[serde(rename_all = "camelCase")]
-pub struct SetDefaultModelResponse {}
-
 /// UserSavedConfig contains a subset of the config. It is meant to expose mcp
 /// client-configurable settings that can be specified in the NewConversation
 /// and SendUserTurn requests.
--- a/codex-rs/protocol/src/models.rs
+++ b/codex-rs/protocol/src/models.rs
@@ -49,7 +49,7 @@ pub enum ResponseItem {
        content: Vec<ContentItem>,
    },
    Reasoning {
-        #[serde(default, skip_serializing)]
+        #[serde(default)]
        id: String,
        summary: Vec<ReasoningItemReasoningSummary>,
        #[serde(default, skip_serializing_if = "should_serialize_reasoning_content")]
@@ -115,6 +115,7 @@ pub enum ResponseItem {
        status: Option<String>,
        action: WebSearchAction,
    },
+
    #[serde(other)]
    Other,
 }
@@ -219,7 +220,7 @@ impl From<Vec<InputItem>> for ResponseInputItem {
                            let mime = mime_guess::from_path(&path)
                                .first()
                                .map(|m| m.essence_str().to_owned())
-                                .unwrap_or_else(|| "image".to_string());
+                                .unwrap_or_else(|| "application/octet-stream".to_string());
                            let encoded = base64::engine::general_purpose::STANDARD.encode(bytes);
                            Some(ContentItem::InputImage {
                                image_url: format!("data:{mime};base64,{encoded}"),
--- a/codex-rs/protocol/src/protocol.rs
+++ b/codex-rs/protocol/src/protocol.rs
@@ -149,7 +149,7 @@ pub enum Op {

    /// Request the full in-memory conversation transcript for the current session.
    /// Reply is delivered via `EventMsg::ConversationHistory`.
-    GetPath,
+    GetHistory,

    /// Request the list of MCP tools available across all configured servers.
    /// Reply is delivered via `EventMsg::McpListToolsResponse`.
@@ -499,7 +499,7 @@ pub enum EventMsg {
    /// Notification that the agent is shutting down.
    ShutdownComplete,

-    ConversationPath(ConversationPathResponseEvent),
+    ConversationHistory(ConversationHistoryResponseEvent),
 }

 // Individual event payload types matching each `EventMsg` variant.
@@ -695,8 +695,6 @@ pub struct UserMessageEvent {
    pub message: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub kind: Option<InputMessageKind>,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub images: Option<Vec<String>>,
 }

 impl<T, U> From<(T, U)> for InputMessageKind
@@ -801,140 +799,9 @@ pub struct WebSearchEndEvent {
 /// Response payload for `Op::GetHistory` containing the current session's
 /// in-memory transcript.
 #[derive(Debug, Clone, Deserialize, Serialize, TS)]
-pub struct ConversationPathResponseEvent {
+pub struct ConversationHistoryResponseEvent {
    pub conversation_id: ConversationId,
-    pub path: PathBuf,
-}
-
-#[derive(Debug, Clone, Deserialize, Serialize, TS)]
-pub struct ResumedHistory {
-    pub conversation_id: ConversationId,
-    pub history: Vec<RolloutItem>,
-    pub rollout_path: PathBuf,
-}
-
-#[derive(Debug, Clone, Deserialize, Serialize, TS)]
-pub enum InitialHistory {
-    New,
-    Resumed(ResumedHistory),
-    Forked(Vec<RolloutItem>),
-}
-
-impl InitialHistory {
-    pub fn get_rollout_items(&self) -> Vec<RolloutItem> {
-        match self {
-            InitialHistory::New => Vec::new(),
-            InitialHistory::Resumed(resumed) => resumed.history.clone(),
-            InitialHistory::Forked(items) => items.clone(),
-        }
-    }
-    pub fn get_response_items(&self) -> Vec<ResponseItem> {
-        match self {
-            InitialHistory::New => Vec::new(),
-            InitialHistory::Resumed(resumed) => resumed
-                .history
-                .iter()
-                .filter_map(|ri| match ri {
-                    RolloutItem::ResponseItem(item) => Some(item.clone()),
-                    _ => None,
-                })
-                .collect(),
-            InitialHistory::Forked(items) => items
-                .iter()
-                .filter_map(|ri| match ri {
-                    RolloutItem::ResponseItem(item) => Some(item.clone()),
-                    _ => None,
-                })
-                .collect(),
-        }
-    }
-    pub fn get_event_msgs(&self) -> Option<Vec<EventMsg>> {
-        match self {
-            InitialHistory::New => None,
-            InitialHistory::Resumed(resumed) => Some(
-                resumed
-                    .history
-                    .iter()
-                    .filter_map(|ri| match ri {
-                        RolloutItem::EventMsg(ev) => Some(ev.clone()),
-                        _ => None,
-                    })
-                    .collect(),
-            ),
-            InitialHistory::Forked(items) => Some(
-                items
-                    .iter()
-                    .filter_map(|ri| match ri {
-                        RolloutItem::EventMsg(ev) => Some(ev.clone()),
-                        _ => None,
-                    })
-                    .collect(),
-            ),
-        }
-    }
-}
-
-#[derive(Serialize, Deserialize, Clone, Default, Debug, TS)]
-pub struct SessionMeta {
-    pub id: ConversationId,
-    pub timestamp: String,
-    pub cwd: PathBuf,
-    pub originator: String,
-    pub cli_version: String,
-    pub instructions: Option<String>,
-}
-
-#[derive(Serialize, Deserialize, Debug, Clone, TS)]
-pub struct SessionMetaLine {
-    #[serde(flatten)]
-    pub meta: SessionMeta,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub git: Option<GitInfo>,
-}
-
-#[derive(Serialize, Deserialize, Debug, Clone, TS)]
-#[serde(tag = "type", content = "payload", rename_all = "snake_case")]
-pub enum RolloutItem {
-    SessionMeta(SessionMetaLine),
-    ResponseItem(ResponseItem),
-    Compacted(CompactedItem),
-    TurnContext(TurnContextItem),
-    EventMsg(EventMsg),
-}
-
-#[derive(Serialize, Deserialize, Clone, Debug, TS)]
-pub struct CompactedItem {
-    pub message: String,
-}
-
-#[derive(Serialize, Deserialize, Clone, Debug, TS)]
-pub struct TurnContextItem {
-    pub cwd: PathBuf,
-    pub approval_policy: AskForApproval,
-    pub sandbox_policy: SandboxPolicy,
-    pub model: String,
-    pub effort: ReasoningEffortConfig,
-    pub summary: ReasoningSummaryConfig,
-}
-
-#[derive(Serialize, Deserialize, Clone)]
-pub struct RolloutLine {
-    pub timestamp: String,
-    #[serde(flatten)]
-    pub item: RolloutItem,
-}
-
-#[derive(Serialize, Deserialize, Clone, Debug, TS)]
-pub struct GitInfo {
-    /// Current commit hash (SHA)
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub commit_hash: Option<String>,
-    /// Current branch name
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub branch: Option<String>,
-    /// Repository URL (if available from remote)
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub repository_url: Option<String>,
+    pub entries: Vec<ResponseItem>,
 }

 #[derive(Debug, Clone, Deserialize, Serialize, TS)]
@@ -1081,9 +948,6 @@ pub struct SessionConfiguredEvent {
    /// Tell the client what model is being queried.
    pub model: String,

-    /// The effort the model is putting into reasoning about the user's request.
-    pub reasoning_effort: ReasoningEffortConfig,
-
    /// Identifier of the history log file (inode on Unix, 0 otherwise).
    pub history_log_id: u64,

@@ -1094,8 +958,6 @@ pub struct SessionConfiguredEvent {
    /// When present, UIs can use these to seed the history.
    #[serde(skip_serializing_if = "Option::is_none")]
    pub initial_messages: Option<Vec<EventMsg>>,
-
-    pub rollout_path: PathBuf,
 }

 /// User's decision in response to an ExecApprovalRequest.
@@ -1158,41 +1020,27 @@ pub enum TurnAbortReason {
 #[cfg(test)]
 mod tests {
    use super::*;
-    use serde_json::json;
-    use tempfile::NamedTempFile;

    /// Serialize Event to verify that its JSON representation has the expected
    /// amount of nesting.
    #[test]
    fn serialize_event() {
        let conversation_id = ConversationId(uuid::uuid!("67e55044-10b1-426f-9247-bb680e5fe0c8"));
-        let rollout_file = NamedTempFile::new().unwrap();
        let event = Event {
            id: "1234".to_string(),
            msg: EventMsg::SessionConfigured(SessionConfiguredEvent {
                session_id: conversation_id,
                model: "codex-mini-latest".to_string(),
-                reasoning_effort: ReasoningEffortConfig::default(),
                history_log_id: 0,
                history_entry_count: 0,
                initial_messages: None,
-                rollout_path: rollout_file.path().to_path_buf(),
            }),
        };
-
-        let expected = json!({
-            "id": "1234",
-            "msg": {
-                "type": "session_configured",
-                "session_id": "67e55044-10b1-426f-9247-bb680e5fe0c8",
-                "model": "codex-mini-latest",
-                "reasoning_effort": "medium",
-                "history_log_id": 0,
-                "history_entry_count": 0,
-                "rollout_path": format!("{}", rollout_file.path().display()),
-            }
-        });
-        assert_eq!(expected, serde_json::to_value(&event).unwrap());
+        let serialized = serde_json::to_string(&event).unwrap();
+        assert_eq!(
+            serialized,
+            r#"{"id":"1234","msg":{"type":"session_configured","session_id":"67e55044-10b1-426f-9247-bb680e5fe0c8","model":"codex-mini-latest","history_log_id":0,"history_entry_count":0}}"#
+        );
    }

    #[test]
--- a/codex-rs/tui/Cargo.toml
+++ b/codex-rs/tui/Cargo.toml
@@ -79,7 +79,7 @@ tokio-stream = "0.1.17"
 tracing = { version = "0.1.41", features = ["log"] }
 tracing-appender = "0.2.3"
 tracing-subscriber = { version = "0.3.19", features = ["env-filter"] }
-pulldown-cmark = "0.10"
+tui-markdown = "0.3.3"
 unicode-segmentation = "1.12.0"
 unicode-width = "0.1"
 url = "2"
--- a/codex-rs/tui/src/app.rs
+++ b/codex-rs/tui/src/app.rs
@@ -11,10 +11,7 @@ use codex_ansi_escape::ansi_escape_line;
 use codex_core::AuthManager;
 use codex_core::ConversationManager;
 use codex_core::config::Config;
-use codex_core::config::persist_model_selection;
-use codex_core::model_family::find_family_for_model;
 use codex_core::protocol::TokenUsage;
-use codex_core::protocol_config_types::ReasoningEffort as ReasoningEffortConfig;
 use color_eyre::eyre::Result;
 use color_eyre::eyre::WrapErr;
 use crossterm::event::KeyCode;
@@ -40,9 +37,6 @@ pub(crate) struct App {

    /// Config is stored here so we can recreate ChatWidgets as needed.
    pub(crate) config: Config,
-    pub(crate) active_profile: Option<String>,
-    model_saved_to_profile: bool,
-    model_saved_to_global: bool,

    pub(crate) file_search: FileSearchManager,

@@ -67,7 +61,6 @@ impl App {
        tui: &mut tui::Tui,
        auth_manager: Arc<AuthManager>,
        config: Config,
-        active_profile: Option<String>,
        initial_prompt: Option<String>,
        initial_images: Vec<PathBuf>,
        resume_selection: ResumeSelection,
@@ -126,9 +119,6 @@ impl App {
            app_event_tx,
            chat_widget,
            config,
-            active_profile,
-            model_saved_to_profile: false,
-            model_saved_to_global: false,
            file_search,
            enhanced_keys_supported,
            transcript_lines: Vec::new(),
@@ -298,17 +288,10 @@ impl App {
                self.chat_widget.apply_file_search_result(query, matches);
            }
            AppEvent::UpdateReasoningEffort(effort) => {
-                self.on_update_reasoning_effort(effort);
+                self.chat_widget.set_reasoning_effort(effort);
            }
            AppEvent::UpdateModel(model) => {
-                self.chat_widget.set_model(model.clone());
-                self.config.model = model.clone();
-                if let Some(family) = find_family_for_model(&model) {
-                    self.config.model_family = family;
-                }
-                self.model_saved_to_profile = false;
-                self.model_saved_to_global = false;
-                self.show_model_save_hint();
+                self.chat_widget.set_model(model);
            }
            AppEvent::UpdateAskForApprovalPolicy(policy) => {
                self.chat_widget.set_approval_policy(policy);
@@ -321,107 +304,7 @@ impl App {
    }

    pub(crate) fn token_usage(&self) -> codex_core::protocol::TokenUsage {
-        self.chat_widget.token_usage()
-    }
-
-    fn show_model_save_hint(&mut self) {
-        let model = self.config.model.clone();
-        if self.active_profile.is_some() {
-            self.chat_widget.add_info_message(format!(
-                "Model switched to {model}. Press Ctrl+S to save it for this profile, then press Ctrl+S again to set it as your global default."
-            ));
-        } else {
-            self.chat_widget.add_info_message(format!(
-                "Model switched to {model}. Press Ctrl+S to save it as your global default."
-            ));
-        }
-    }
-
-    fn on_update_reasoning_effort(&mut self, effort: ReasoningEffortConfig) {
-        let changed = self.config.model_reasoning_effort != effort;
-        self.chat_widget.set_reasoning_effort(effort);
-        self.config.model_reasoning_effort = effort;
-        if changed {
-            let show_hint = self.model_saved_to_profile || self.model_saved_to_global;
-            self.model_saved_to_profile = false;
-            self.model_saved_to_global = false;
-            if show_hint {
-                self.show_model_save_hint();
-            }
-        }
-    }
-
-    async fn persist_model_shortcut(&mut self) {
-        enum SaveScope<'a> {
-            Profile(&'a str),
-            Global,
-            AlreadySaved,
-        }
-
-        let scope = if let Some(profile) = self
-            .active_profile
-            .as_deref()
-            .filter(|_| !self.model_saved_to_profile)
-        {
-            SaveScope::Profile(profile)
-        } else if !self.model_saved_to_global {
-            SaveScope::Global
-        } else {
-            SaveScope::AlreadySaved
-        };
-
-        let model = self.config.model.clone();
-        let effort = self.config.model_reasoning_effort;
-        let codex_home = self.config.codex_home.clone();
-
-        match scope {
-            SaveScope::Profile(profile) => {
-                match persist_model_selection(&codex_home, Some(profile), &model, Some(effort))
-                    .await
-                {
-                    Ok(()) => {
-                        self.model_saved_to_profile = true;
-                        self.chat_widget.add_info_message(format!(
-                            "Saved model {model} ({effort}) for profile `{profile}`. Press Ctrl+S again to make this your global default."
-                        ));
-                    }
-                    Err(err) => {
-                        tracing::error!(
-                            error = %err,
-                            "failed to persist model selection via shortcut"
-                        );
-                        self.chat_widget.add_error_message(format!(
-                            "Failed to save model preference for profile `{profile}`: {err}"
-                        ));
-                    }
-                }
-            }
-            SaveScope::Global => {
-                match persist_model_selection(&codex_home, None, &model, Some(effort)).await {
-                    Ok(()) => {
-                        self.model_saved_to_global = true;
-                        self.chat_widget.add_info_message(format!(
-                            "Saved model {model} ({effort}) as your global default."
-                        ));
-                    }
-                    Err(err) => {
-                        tracing::error!(
-                            error = %err,
-                            "failed to persist global model selection via shortcut"
-                        );
-                        self.chat_widget.add_error_message(format!(
-                            "Failed to save global model preference: {err}"
-                        ));
-                    }
-                }
-            }
-            SaveScope::AlreadySaved => {
-                self.chat_widget.add_info_message(
-                    "Model preference already saved globally; no further action needed."
-                        .to_string(),
-                );
-            }
-        }
+        self.chat_widget.token_usage().clone()
    }

    async fn handle_key_event(&mut self, tui: &mut tui::Tui, key_event: KeyEvent) {
@@ -437,14 +320,6 @@ impl App {
                self.overlay = Some(Overlay::new_transcript(self.transcript_lines.clone()));
                tui.frame_requester().schedule_frame();
            }
-            KeyEvent {
-                code: KeyCode::Char('s'),
-                modifiers: crossterm::event::KeyModifiers::CONTROL,
-                kind: KeyEventKind::Press,
-                ..
-            } => {
-                self.persist_model_shortcut().await;
-            }
            // Esc primes/advances backtracking only in normal (not working) mode
            // with an empty composer. In any other state, forward Esc so the
            // active UI (e.g. status indicator, modals, popups) handles it.
@@ -491,67 +366,3 @@ impl App {
        };
    }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::app_backtrack::BacktrackState;
-    use crate::chatwidget::tests::make_chatwidget_manual_with_sender;
-    use crate::file_search::FileSearchManager;
-    use codex_core::CodexAuth;
-    use codex_core::ConversationManager;
-    use ratatui::text::Line;
-    use std::sync::Arc;
-    use std::sync::atomic::AtomicBool;
-
-    fn make_test_app() -> App {
-        let (chat_widget, app_event_tx, _rx, _op_rx) = make_chatwidget_manual_with_sender();
-        let config = chat_widget.config_ref().clone();
-
-        let server = Arc::new(ConversationManager::with_auth(CodexAuth::from_api_key(
-            "Test API Key",
-        )));
-        let file_search = FileSearchManager::new(config.cwd.clone(), app_event_tx.clone());
-
-        App {
-            server,
-            app_event_tx,
-            chat_widget,
-            config,
-            active_profile: None,
-            model_saved_to_profile: false,
-            model_saved_to_global: false,
-            file_search,
-            transcript_lines: Vec::<Line<'static>>::new(),
-            overlay: None,
-            deferred_history_lines: Vec::new(),
-            has_emitted_history_lines: false,
-            enhanced_keys_supported: false,
-            commit_anim_running: Arc::new(AtomicBool::new(false)),
-            backtrack: BacktrackState::default(),
-        }
-    }
-
-    #[test]
-    fn update_reasoning_effort_updates_config_and_resets_flags() {
-        let mut app = make_test_app();
-        app.model_saved_to_profile = true;
-        app.model_saved_to_global = true;
-        app.config.model_reasoning_effort = ReasoningEffortConfig::Medium;
-        app.chat_widget
-            .set_reasoning_effort(ReasoningEffortConfig::Medium);
-
-        app.on_update_reasoning_effort(ReasoningEffortConfig::High);
-
-        assert_eq!(
-            app.config.model_reasoning_effort,
-            ReasoningEffortConfig::High
-        );
-        assert_eq!(
-            app.chat_widget.config_ref().model_reasoning_effort,
-            ReasoningEffortConfig::High
-        );
-        assert!(!app.model_saved_to_profile);
-        assert!(!app.model_saved_to_global);
-    }
-}
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Kazuhiro Sera	19606f0b36	Merge branch 'main' into user-friendly-error-handling	2025-09-09 10:21:08 +09:00
Kazuhiro Sera	f08b08680f	Merge branch 'main' into user-friendly-error-handling	2025-08-25 10:12:02 +09:00
Kazuhiro Sera	55d876404b	Merge branch 'main' into user-friendly-error-handling	2025-08-24 10:37:37 +09:00
Kazuhiro Sera	efd82025a5	fix: #2606 better user experience with unrecoverable errors	2025-08-23 13:04:06 +09:00