Merge branch 'main' into codex-concurrent-simple

.github/actions/codex/bun.lock

@@ -11,7 +11,7 @@
         "@types/bun": "^1.2.19",
         "@types/node": "^24.1.0",
         "prettier": "^3.6.2",
-        "typescript": "^5.9.2",
+        "typescript": "^5.8.3",
       },
     },
   },
@@ -68,7 +68,7 @@
 
     "tunnel": ["tunnel@0.0.6", "", {}, "sha512-1h/Lnq9yajKY2PEbBadPXj3VxsDDu844OnaAo52UVmIzIvwwtBPIuNvkjuzBlTWpfJyUbG3ez0KSBibQkj4ojg=="],
 
-    "typescript": ["typescript@5.9.2", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-CWBzXQrc/qOkhidw1OzBTQuYRbfyxDXJMVJ1XNwUHGROVmuaeiEm3OslpZ1RV96d7SKKjZKrSJu3+t/xlw3R9A=="],
+    "typescript": ["typescript@5.8.3", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-p1diW6TqL9L07nNxvRMM7hMMw4c5XOo/1ibL4aAIGmSAt9slTE1Xgw5KWuof2uTOvCg9BY7ZRi+GaF+7sfgPeQ=="],
 
     "undici": ["undici@5.29.0", "", { "dependencies": { "@fastify/busboy": "^2.0.0" } }, "sha512-raqeBD6NQK4SkWhQzeYKd1KmIG6dllBOTt55Rmkt4HtI9mwdWtJljnrXjAFUBLTSN67HWrOIZ3EPF4kjUw80Bg=="],
 

.github/actions/codex/package.json

@@ -16,6 +16,6 @@
         "@types/bun": "^1.2.19",
         "@types/node": "^24.1.0",
         "prettier": "^3.6.2",
-        "typescript": "^5.9.2"
+        "typescript": "^5.8.3"
     }
 }

codex-cli/src/utils/agent/sandbox/macos-seatbelt.ts

@@ -147,8 +147,4 @@ const READ_ONLY_SEATBELT_POLICY = `
   (sysctl-name "kern.version")
   (sysctl-name "sysctl.proc_cputype")
   (sysctl-name-prefix "hw.perflevel")
-)
-
-; Added on top of Chrome profile
-; Needed for python multiprocessing on MacOS for the SemLock
-(allow ipc-posix-sem)`.trim();
+)`.trim();

codex-rs/Cargo.lock

@@ -661,7 +661,7 @@ dependencies = [
  "clap",
  "codex-core",
  "serde",
- "toml 0.9.4",
+ "toml 0.9.2",
 ]
 
 [[package]]
@@ -699,7 +699,6 @@ dependencies = [
  "serde_json",
  "sha1",
  "shlex",
- "similar",
  "strum_macros 0.27.2",
  "tempfile",
  "thiserror 2.0.12",
@@ -707,7 +706,7 @@ dependencies = [
  "tokio",
  "tokio-test",
  "tokio-util",
- "toml 0.9.4",
+ "toml 0.9.2",
  "tracing",
  "tree-sitter",
  "tree-sitter-bash",
@@ -831,7 +830,7 @@ dependencies = [
  "tempfile",
  "tokio",
  "tokio-test",
- "toml 0.9.4",
+ "toml 0.9.2",
  "tracing",
  "tracing-subscriber",
  "uuid",
@@ -860,7 +859,6 @@ dependencies = [
  "mcp-types",
  "path-clean",
  "pretty_assertions",
- "rand 0.8.5",
  "ratatui",
  "ratatui-image",
  "regex-lite",
@@ -870,14 +868,13 @@ dependencies = [
  "shlex",
  "strum 0.27.2",
  "strum_macros 0.27.2",
- "supports-color",
- "textwrap 0.16.2",
  "tokio",
  "tracing",
  "tracing-appender",
  "tracing-subscriber",
  "tui-input",
  "tui-markdown",
+ "tui-textarea",
  "unicode-segmentation",
  "unicode-width 0.1.14",
  "uuid",
@@ -2017,7 +2014,7 @@ dependencies = [
  "libc",
  "percent-encoding",
  "pin-project-lite",
- "socket2",
+ "socket2 0.6.0",
  "system-configuration",
  "tokio",
  "tower-service",
@@ -2339,12 +2336,6 @@ dependencies = [
  "windows-sys 0.59.0",
 ]
 
-[[package]]
-name = "is_ci"
-version = "1.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7655c9839580ee829dfacba1d1278c2b7883e50a277ff7541299489d6bdfdc45"
-
 [[package]]
 name = "is_terminal_polyfill"
 version = "1.70.1"
@@ -3997,9 +3988,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.142"
+version = "1.0.141"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "030fedb782600dcbd6f02d479bf0d817ac3bb40d644745b769d6a96bc3afc5a7"
+checksum = "30b9eff21ebe718216c6ec64e1d9ac57087aad11efc64e32002bce4a0d4c03d3"
 dependencies = [
  "indexmap 2.10.0",
  "itoa",
@@ -4183,10 +4174,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
 
 [[package]]
-name = "smawk"
-version = "0.3.2"
+name = "socket2"
+version = "0.5.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b7c388c1b5e93756d0c740965c41e8822f866621d41acbdf6336a6a168f8840c"
+checksum = "e22376abed350d73dd1cd119b57ffccad95b4e585a7cda43e286245ce23c0678"
+dependencies = [
+ "libc",
+ "windows-sys 0.52.0",
+]
 
 [[package]]
 name = "socket2"
@@ -4240,7 +4235,7 @@ dependencies = [
  "starlark_syntax",
  "static_assertions",
  "strsim 0.10.0",
- "textwrap 0.11.0",
+ "textwrap",
  "thiserror 1.0.69",
 ]
 
@@ -4376,15 +4371,6 @@ version = "2.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "13c2bddecc57b384dee18652358fb23172facb8a2c51ccc10d74c157bdea3292"
 
-[[package]]
-name = "supports-color"
-version = "3.0.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c64fc7232dd8d2e4ac5ce4ef302b1d81e0b80d055b9d77c7c4f51f6aa4c867d6"
-dependencies = [
- "is_ci",
-]
-
 [[package]]
 name = "syn"
 version = "1.0.109"
@@ -4538,17 +4524,6 @@ dependencies = [
  "unicode-width 0.1.14",
 ]
 
-[[package]]
-name = "textwrap"
-version = "0.16.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c13547615a44dc9c452a8a534638acdf07120d4b6847c8178705da06306a3057"
-dependencies = [
- "smawk",
- "unicode-linebreak",
- "unicode-width 0.2.0",
-]
-
 [[package]]
 name = "thiserror"
 version = "1.0.69"
@@ -4663,9 +4638,9 @@ dependencies = [
 
 [[package]]
 name = "tokio"
-version = "1.47.1"
+version = "1.46.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "89e49afdadebb872d3145a5638b59eb0691ea23e46ca484037cfab3b76b95038"
+checksum = "0cc3a2344dafbe23a245241fe8b09735b521110d30fcefbbd5feb1797ca35d17"
 dependencies = [
  "backtrace",
  "bytes",
@@ -4676,9 +4651,9 @@ dependencies = [
  "pin-project-lite",
  "signal-hook-registry",
  "slab",
- "socket2",
+ "socket2 0.5.10",
  "tokio-macros",
- "windows-sys 0.59.0",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]
@@ -4763,9 +4738,9 @@ dependencies = [
 
 [[package]]
 name = "toml"
-version = "0.9.4"
+version = "0.9.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "41ae868b5a0f67631c14589f7e250c1ea2c574ee5ba21c6c8dd4b1485705a5a1"
+checksum = "ed0aee96c12fa71097902e0bb061a5e1ebd766a6636bb605ba401c45c1650eac"
 dependencies = [
  "indexmap 2.10.0",
  "serde",
@@ -5013,6 +4988,17 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "tui-textarea"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0a5318dd619ed73c52a9417ad19046724effc1287fb75cdcc4eca1d6ac1acbae"
+dependencies = [
+ "crossterm",
+ "ratatui",
+ "unicode-width 0.2.0",
+]
+
 [[package]]
 name = "typenum"
 version = "1.18.0"
@@ -5031,12 +5017,6 @@ version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5a5f39404a5da50712a4c1eecf25e90dd62b613502b7e925fd4e4d19b5c96512"
 
-[[package]]
-name = "unicode-linebreak"
-version = "0.1.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3b09c83c3c29d37506a3e260c08c03743a6bb66a9cd432c6934ab501a190571f"
-
 [[package]]
 name = "unicode-segmentation"
 version = "1.12.0"

codex-rs/cli/src/concurrent/mod.rs

@@ -0,0 +1,584 @@
+use std::fs::File;
+use std::io::Write;
+use std::path::Path;
+use std::path::PathBuf;
+use std::process::Command;
+use std::process::Stdio;
+use std::sync::OnceLock;
+
+use tokio::process::Command as TokioCommand;
+use tokio::sync::Semaphore;
+
+use anyhow::Context;
+use codex_common::CliConfigOverrides;
+use codex_exec::Cli as ExecCli;
+
+// Serialize git worktree add operations across tasks to avoid repository lock contention.
+static GIT_WORKTREE_ADD_SEMAPHORE: OnceLock<Semaphore> = OnceLock::new();
+
+#[derive(Debug, Clone)]
+pub struct ConcurrentRunResult {
+    pub branch: String,
+    pub worktree_dir: PathBuf,
+    pub log_file: Option<PathBuf>,
+    pub exec_exit_code: Option<i32>,
+    pub _had_changes: bool,
+    pub _applied_changes: Option<usize>,
+}
+
+fn compute_codex_home() -> PathBuf {
+    if let Ok(val) = std::env::var("CODEX_HOME") {
+        if !val.is_empty() {
+            return PathBuf::from(val);
+        }
+    }
+    // Fallback to default (~/.codex) without requiring it to already exist.
+    codex_core::config::find_codex_home().unwrap_or_else(|_| {
+        let mut p = std::env::var_os("HOME")
+            .map(PathBuf::from)
+            .unwrap_or_default();
+        if p.as_os_str().is_empty() {
+            return PathBuf::from(".codex");
+        }
+        p.push(".codex");
+        p
+    })
+}
+
+fn slugify_prompt(prompt: &str, max_len: usize) -> String {
+    let mut out = String::with_capacity(prompt.len());
+    let mut prev_hyphen = false;
+    for ch in prompt.chars() {
+        let c = ch.to_ascii_lowercase();
+        let keep = matches!(c, 'a'..='z' | '0'..='9');
+        if keep {
+            out.push(c);
+            prev_hyphen = false;
+        } else if c.is_ascii_whitespace() || matches!(c, '-' | '_' | '+') {
+            if !prev_hyphen && !out.is_empty() {
+                out.push('-');
+                prev_hyphen = true;
+            }
+        } else {
+            // skip other punctuation/symbols
+        }
+        if out.len() >= max_len {
+            break;
+        }
+    }
+    // Trim trailing hyphens
+    while out.ends_with('-') {
+        out.pop();
+    }
+    if out.is_empty() {
+        "task".to_string()
+    } else {
+        out
+    }
+}
+
+fn git_output(repo_dir: &Path, args: &[&str]) -> anyhow::Result<String> {
+    let out = Command::new("git")
+        .args(args)
+        .current_dir(repo_dir)
+        .output()
+        .with_context(|| format!("running git {args:?}"))?;
+    if !out.status.success() {
+        anyhow::bail!(
+            "git {:?} failed with status {}: {}",
+            args,
+            out.status,
+            String::from_utf8_lossy(&out.stderr)
+        );
+    }
+    Ok(String::from_utf8_lossy(&out.stdout).trim().to_string())
+}
+
+fn git_capture_stdout(repo_dir: &Path, args: &[&str]) -> anyhow::Result<Vec<u8>> {
+    let out = Command::new("git")
+        .args(args)
+        .current_dir(repo_dir)
+        .output()
+        .with_context(|| format!("running git {args:?}"))?;
+    if !out.status.success() {
+        anyhow::bail!(
+            "git {:?} failed with status {}: {}",
+            args,
+            out.status,
+            String::from_utf8_lossy(&out.stderr)
+        );
+    }
+    Ok(out.stdout)
+}
+
+fn count_files_in_patch(diff: &[u8]) -> usize {
+    // Count occurrences of lines starting with "diff --git ", which mark file boundaries.
+    // This works for text and binary patches produced by `git diff --binary`.
+    let mut count = 0usize;
+    for line in diff.split(|&b| b == b'\n') {
+        if line.starts_with(b"diff --git ") {
+            count += 1;
+        }
+    }
+    count
+}
+
+pub async fn run_concurrent_flow(
+    prompt: String,
+    cli_config_overrides: CliConfigOverrides,
+    codex_linux_sandbox_exe: Option<PathBuf>,
+    automerge: bool,
+    quiet: bool,
+) -> anyhow::Result<ConcurrentRunResult> {
+    let cwd = std::env::current_dir()?;
+
+    // Ensure we are in a git repo and find repo root.
+    let repo_root_str = git_output(&cwd, &["rev-parse", "--show-toplevel"]);
+    let repo_root = match repo_root_str {
+        Ok(p) => PathBuf::from(p),
+        Err(err) => {
+            eprintln!("Not inside a Git repo: {err}");
+            std::process::exit(1);
+        }
+    };
+
+    // Determine current branch and original head commit.
+    let current_branch = git_output(&repo_root, &["rev-parse", "--abbrev-ref", "HEAD"])
+        .unwrap_or_else(|_| "HEAD".to_string());
+    let original_head =
+        git_output(&repo_root, &["rev-parse", "HEAD"]).context("finding original HEAD commit")?;
+
+    // Build worktree target path under $CODEX_HOME/worktrees/<repo>/<branch>
+    let mut codex_home = compute_codex_home();
+    codex_home.push("worktrees");
+    // repo name = last component of repo_root
+    let repo_name = repo_root
+        .file_name()
+        .map(|s| s.to_string_lossy().to_string())
+        .unwrap_or_else(|| "repo".to_string());
+    codex_home.push(repo_name.clone());
+
+    // Prepare branch name: codex/<slug>, retrying with a numeric suffix to avoid races.
+    let slug = slugify_prompt(&prompt, 64);
+    let mut branch: String;
+    let worktree_dir: PathBuf;
+    let mut attempt: u32 = 1;
+    loop {
+        branch = if attempt == 1 {
+            format!("codex/{slug}")
+        } else {
+            format!("codex/{slug}-{attempt}")
+        };
+
+        let mut candidate_dir = codex_home.clone();
+        candidate_dir.push(&branch);
+
+        // Create parent directories for candidate path.
+        if let Some(parent) = candidate_dir.parent() {
+            std::fs::create_dir_all(parent)?;
+        }
+
+        if !quiet {
+            println!(
+                "Creating worktree at {} with branch {}",
+                candidate_dir.display(),
+                branch
+            );
+        }
+
+        // Try to add worktree with new branch from current HEAD
+        let worktree_path_str = candidate_dir.to_string_lossy().to_string();
+        let add_status = Command::new("git")
+            .arg("worktree")
+            .arg("add")
+            .arg("-b")
+            .arg(&branch)
+            .arg(&worktree_path_str)
+            .current_dir(&repo_root)
+            .status()?;
+        if add_status.success() {
+            worktree_dir = candidate_dir;
+            break;
+        }
+
+        attempt += 1;
+        if attempt > 50 {
+            anyhow::bail!("Failed to create git worktree after multiple attempts");
+        }
+        // Retry with a new branch name.
+    }
+
+    // Either run codex exec inline (verbose) or as a subprocess with logs redirected.
+    let mut log_file: Option<PathBuf> = None;
+    let mut exec_exit_code: Option<i32> = None;
+    if quiet {
+        let exe = std::env::current_exe()
+            .map_err(|e| anyhow::anyhow!("failed to locate current executable: {e}"))?;
+
+        // Prepare logs directory: $CODEX_HOME/logs/<repo_name>
+        let mut logs_dir = compute_codex_home();
+        logs_dir.push("logs");
+        logs_dir.push(&repo_name);
+        std::fs::create_dir_all(&logs_dir)?;
+
+        let sanitized_branch = branch.replace('/', "_");
+        let log_path = logs_dir.join(format!("{sanitized_branch}.log"));
+        let log_f = File::create(&log_path)?;
+        log_file = Some(log_path.clone());
+
+        let mut cmd = Command::new(exe);
+        cmd.arg("exec")
+            .arg("--full-auto")
+            .arg("--cd")
+            .arg(worktree_dir.as_os_str())
+            .stdout(Stdio::from(log_f.try_clone()?))
+            .stderr(Stdio::from(log_f));
+
+        // Forward any root-level config overrides.
+        for ov in cli_config_overrides.raw_overrides.iter() {
+            cmd.arg("-c").arg(ov);
+        }
+
+        // Append the prompt last (positional argument).
+        cmd.arg(&prompt);
+
+        let status = cmd.status()?;
+        exec_exit_code = status.code();
+        if !status.success() && !quiet {
+            eprintln!("codex exec failed with exit code {exec_exit_code:?}");
+        }
+    } else {
+        // Build an ExecCli to run in full-auto mode at the worktree directory.
+        let mut exec_cli = ExecCli {
+            images: vec![],
+            model: None,
+            sandbox_mode: None,
+            config_profile: None,
+            full_auto: true,
+            dangerously_bypass_approvals_and_sandbox: false,
+            cwd: Some(worktree_dir.clone()),
+            skip_git_repo_check: false,
+            config_overrides: CliConfigOverrides::default(),
+            color: Default::default(),
+            json: false,
+            last_message_file: None,
+            prompt: Some(prompt.clone()),
+        };
+
+        // Prepend any root-level config overrides.
+        super::prepend_config_flags(&mut exec_cli.config_overrides, cli_config_overrides);
+
+        // Run codex exec
+        if let Err(e) = codex_exec::run_main(exec_cli, codex_linux_sandbox_exe).await {
+            eprintln!("codex exec failed: {e}");
+            // Do not attempt to bring changes on failure; leave worktree for inspection.
+            return Err(e);
+        }
+    }
+
+    // Auto-commit changes in the worktree if any
+    let status_out = Command::new("git")
+        .args(["status", "--porcelain"])
+        .current_dir(&worktree_dir)
+        .output()?;
+    let status_text = String::from_utf8_lossy(&status_out.stdout);
+    let had_changes = !status_text.trim().is_empty();
+    if had_changes {
+        // Stage and commit
+        if !Command::new("git")
+            .args(["add", "-A"])
+            .current_dir(&worktree_dir)
+            .status()?
+            .success()
+        {
+            anyhow::bail!("git add failed in worktree");
+        }
+        let commit_message = format!("Codex concurrent: {prompt}");
+        if !Command::new("git")
+            .args(["commit", "-m", &commit_message])
+            .current_dir(&worktree_dir)
+            .status()?
+            .success()
+        {
+            if !quiet {
+                eprintln!("No commit created (maybe no changes)");
+            }
+        } else if !quiet {
+            println!("Committed changes in worktree branch {branch}");
+        }
+    } else if !quiet {
+        println!("No changes detected in worktree; skipping commit.");
+    }
+
+    if !automerge {
+        if !quiet {
+            println!(
+                "Auto-merge disabled; leaving changes in worktree {} on branch {}.",
+                worktree_dir.display(),
+                branch
+            );
+            println!(
+                "You can review and manually merge from that branch into {current_branch} when ready."
+            );
+            println!("Summary: Auto-merge disabled.");
+        }
+        return Ok(ConcurrentRunResult {
+            branch,
+            worktree_dir,
+            log_file,
+            exec_exit_code,
+            _had_changes: had_changes,
+            _applied_changes: None,
+        });
+    }
+
+    // Bring the changes into the main working tree as UNSTAGED modifications.
+    // We generate a patch from the original HEAD to the worktree branch tip, then apply with 3-way merge.
+    if !quiet {
+        println!("Applying changes from {branch} onto {current_branch} as unstaged modifications");
+    }
+    let range = format!("{original_head}..{branch}");
+    let mut diff_bytes =
+        git_capture_stdout(&repo_root, &["diff", "--binary", "--full-index", &range])?;
+
+    // Fallback: if there is nothing in the commit range (e.g., commit didn't happen),
+    // try to capture uncommitted changes from the worktree working tree.
+    if diff_bytes.is_empty() && had_changes {
+        // If we saw changes earlier but no commit diff was produced, fall back to working tree diff.
+        // This captures unstaged changes relative to HEAD in the worktree.
+        diff_bytes =
+            git_capture_stdout(&worktree_dir, &["diff", "--binary", "--full-index", "HEAD"])?;
+    }
+
+    if diff_bytes.is_empty() {
+        if !quiet {
+            println!("Summary: 0 changes detected.");
+        }
+        return Ok(ConcurrentRunResult {
+            branch,
+            worktree_dir,
+            log_file,
+            exec_exit_code,
+            _had_changes: had_changes,
+            _applied_changes: Some(0),
+        });
+    }
+
+    let changed_files = count_files_in_patch(&diff_bytes);
+
+    let mut child = Command::new("git")
+        .arg("apply")
+        .arg("-3")
+        .stdin(Stdio::piped())
+        .stdout(Stdio::inherit())
+        .stderr(Stdio::inherit())
+        .current_dir(&repo_root)
+        .spawn()
+        .context("spawning git apply")?;
+    if let Some(stdin) = child.stdin.as_mut() {
+        stdin
+            .write_all(&diff_bytes)
+            .context("writing patch to git apply stdin")?;
+    }
+    let status = child.wait().context("waiting for git apply")?;
+    if !status.success() {
+        if !quiet {
+            eprintln!(
+                "Applying changes failed. You can manually inspect {} and apply diffs.",
+                worktree_dir.display()
+            );
+            println!("Summary: Apply failed.");
+        }
+    } else {
+        if !quiet {
+            println!("Changes applied to working tree (unstaged).");
+            println!("Summary: Applied {changed_files} files changed.");
+        }
+
+        // Cleanup: remove the worktree and delete the temporary branch.
+        if !quiet {
+            println!(
+                "Cleaning up worktree {} and branch {}",
+                worktree_dir.display(),
+                branch
+            );
+        }
+        let worktree_path_str = worktree_dir.to_string_lossy().to_string();
+        let remove_status = Command::new("git")
+            .args(["worktree", "remove", &worktree_path_str])
+            .current_dir(&repo_root)
+            .status();
+        match remove_status {
+            Ok(s) if s.success() => {
+                // removed
+            }
+            _ => {
+                if !quiet {
+                    eprintln!("git worktree remove failed; retrying with --force");
+                }
+                let _ = Command::new("git")
+                    .args(["worktree", "remove", "--force", &worktree_path_str])
+                    .current_dir(&repo_root)
+                    .status();
+            }
+        }
+
+        let del_status = Command::new("git")
+            .args(["branch", "-D", &branch])
+            .current_dir(&repo_root)
+            .status();
+        if let Ok(s) = del_status {
+            if !s.success() && !quiet {
+                eprintln!("Failed to delete branch {branch}");
+            }
+        } else if !quiet {
+            eprintln!("Error running git branch -D {branch}");
+        }
+    }
+
+    Ok(ConcurrentRunResult {
+        branch,
+        worktree_dir,
+        log_file,
+        exec_exit_code,
+        _had_changes: had_changes,
+        _applied_changes: Some(changed_files),
+    })
+}
+
+/// A Send-friendly variant used for best-of-n: run quietly (logs redirected) and do not auto-merge.
+/// This intentionally avoids referencing non-Send types from codex-exec.
+pub async fn run_concurrent_flow_quiet_no_automerge(
+    prompt: String,
+    cli_config_overrides: CliConfigOverrides,
+    _codex_linux_sandbox_exe: Option<PathBuf>,
+) -> anyhow::Result<ConcurrentRunResult> {
+    let cwd = std::env::current_dir()?;
+
+    let repo_root_str = git_output(&cwd, &["rev-parse", "--show-toplevel"]);
+    let repo_root = match repo_root_str {
+        Ok(p) => PathBuf::from(p),
+        Err(err) => {
+            eprintln!("Not inside a Git repo: {err}");
+            std::process::exit(1);
+        }
+    };
+
+    // Capture basic repo info (not used further in quiet/no-automerge flow).
+
+    let mut codex_home = compute_codex_home();
+    codex_home.push("worktrees");
+    let repo_name = repo_root
+        .file_name()
+        .map(|s| s.to_string_lossy().to_string())
+        .unwrap_or_else(|| "repo".to_string());
+    codex_home.push(repo_name.clone());
+
+    let slug = slugify_prompt(&prompt, 64);
+    let mut branch: String;
+    let worktree_dir: PathBuf;
+    // Serialize worktree creation to avoid git repo lock contention across tasks.
+    {
+        let semaphore = GIT_WORKTREE_ADD_SEMAPHORE.get_or_init(|| Semaphore::new(1));
+        let _permit = semaphore.acquire().await.expect("semaphore closed");
+
+        let mut attempt: u32 = 1;
+        loop {
+            branch = if attempt == 1 {
+                format!("codex/{slug}")
+            } else {
+                format!("codex/{slug}-{attempt}")
+            };
+
+            let mut candidate_dir = codex_home.clone();
+            candidate_dir.push(&branch);
+
+            if let Some(parent) = candidate_dir.parent() {
+                std::fs::create_dir_all(parent)?;
+            }
+
+            let worktree_path_str = candidate_dir.to_string_lossy().to_string();
+            let add_status = TokioCommand::new("git")
+                .arg("worktree")
+                .arg("add")
+                .arg("-b")
+                .arg(&branch)
+                .arg(&worktree_path_str)
+                .current_dir(&repo_root)
+                .status()
+                .await?;
+            if add_status.success() {
+                worktree_dir = candidate_dir;
+                break;
+            }
+            attempt += 1;
+            if attempt > 50 {
+                anyhow::bail!("Failed to create git worktree after multiple attempts");
+            }
+        }
+    }
+
+    // Run the CLI in quiet mode (logs redirected).
+    let exe = std::env::current_exe()
+        .map_err(|e| anyhow::anyhow!("failed to locate current executable: {e}"))?;
+
+    let mut logs_dir = compute_codex_home();
+    logs_dir.push("logs");
+    logs_dir.push(&repo_name);
+    std::fs::create_dir_all(&logs_dir)?;
+
+    let sanitized_branch = branch.replace('/', "_");
+    let log_path = logs_dir.join(format!("{sanitized_branch}.log"));
+    let log_f = File::create(&log_path)?;
+    let log_file = Some(log_path.clone());
+
+    let mut cmd = TokioCommand::new(exe);
+    cmd.arg("exec")
+        .arg("--full-auto")
+        .arg("--cd")
+        .arg(worktree_dir.as_os_str())
+        .stdout(Stdio::from(log_f.try_clone()?))
+        .stderr(Stdio::from(log_f));
+    for ov in cli_config_overrides.raw_overrides.iter() {
+        cmd.arg("-c").arg(ov);
+    }
+    cmd.arg(&prompt);
+
+    let status = cmd.status().await?;
+    let exec_exit_code = status.code();
+
+    // Auto-commit changes in the worktree if any
+    let status_out = TokioCommand::new("git")
+        .args(["status", "--porcelain"])
+        .current_dir(&worktree_dir)
+        .output()
+        .await?;
+    let status_text = String::from_utf8_lossy(&status_out.stdout);
+    let had_changes = !status_text.trim().is_empty();
+    if had_changes {
+        if !TokioCommand::new("git")
+            .args(["add", "-A"])
+            .current_dir(&worktree_dir)
+            .status()
+            .await?
+            .success()
+        {
+            anyhow::bail!("git add failed in worktree");
+        }
+        let commit_message = format!("Codex concurrent: {prompt}");
+        let _ = TokioCommand::new("git")
+            .args(["commit", "-m", &commit_message])
+            .current_dir(&worktree_dir)
+            .status()
+            .await?;
+    }
+
+    Ok(ConcurrentRunResult {
+        branch,
+        worktree_dir,
+        log_file,
+        exec_exit_code,
+        _had_changes: had_changes,
+        _applied_changes: None,
+    })
+}

codex-rs/cli/src/main.rs

@@ -17,6 +17,7 @@ use codex_tui::Cli as TuiCli;
 use std::path::PathBuf;
 
 use crate::proto::ProtoCli;
+mod concurrent;
 
 /// Codex CLI
 ///
@@ -32,6 +33,22 @@ struct MultitoolCli {
     #[clap(flatten)]
     pub config_overrides: CliConfigOverrides,
 
+    /// Experimental:Launch a concurrent task in a separate Git worktree using the given prompt.
+    /// Creates worktree under $CODEX_HOME/worktrees/<repo>/codex/<slug> and runs `codex exec` in full-auto mode.
+    #[arg(long = "concurrent", value_name = "PROMPT")]
+    pub concurrent: Option<String>,
+
+    /// When using --concurrent, also attempt to auto-merge the resulting changes
+    /// back into the current working tree as unstaged modifications via
+    /// a 3-way git apply. Disable with --automerge=false.
+    #[arg(long = "automerge", default_value_t = true, action = clap::ArgAction::Set)]
+    pub automerge: bool,
+
+    /// Run the same --concurrent prompt N times in separate worktrees and keep them all.
+    /// Intended to generate multiple candidate solutions without auto-merging.
+    #[arg(long = "best-of-n", value_name = "N", default_value_t = 1)]
+    pub best_of_n: usize,
+
     #[clap(flatten)]
     interactive: TuiCli,
 
@@ -116,6 +133,87 @@ fn main() -> anyhow::Result<()> {
 async fn cli_main(codex_linux_sandbox_exe: Option<PathBuf>) -> anyhow::Result<()> {
     let cli = MultitoolCli::parse();
 
+    // Handle --concurrent at the root level.
+    if let Some(prompt) = cli.concurrent.clone() {
+        if cli.subcommand.is_some() {
+            eprintln!("--concurrent cannot be used together with a subcommand");
+            std::process::exit(2);
+        }
+        let runs = if cli.best_of_n == 0 { 1 } else { cli.best_of_n };
+        if runs > 1 {
+            println!(
+                "Running best-of-n with {runs} runs; auto-merge will be disabled and worktrees kept."
+            );
+
+            // Launch all runs concurrently and collect results as they finish.
+            let mut join_set = tokio::task::JoinSet::new();
+            for _ in 0..runs {
+                let prompt = prompt.clone();
+                let overrides = cli.config_overrides.clone();
+                let sandbox = codex_linux_sandbox_exe.clone();
+                join_set.spawn(async move {
+                    concurrent::run_concurrent_flow_quiet_no_automerge(prompt, overrides, sandbox)
+                        .await
+                });
+            }
+
+            let mut results: Vec<concurrent::ConcurrentRunResult> = Vec::with_capacity(runs);
+            while let Some(join_result) = join_set.join_next().await {
+                match join_result {
+                    Ok(Ok(res)) => {
+                        println!(
+                            "task finished for branch: {}\n, directory: {}",
+                            res.branch,
+                            res.worktree_dir.display()
+                        );
+                        results.push(res);
+                    }
+                    Ok(Err(err)) => {
+                        eprintln!("concurrent task failed: {err}");
+                    }
+                    Err(join_err) => {
+                        eprintln!("failed to join concurrent task: {join_err}");
+                    }
+                }
+            }
+
+            println!("\nBest-of-n summary:");
+            for r in &results {
+                let status = match r.exec_exit_code {
+                    Some(0) => "OK",
+                    Some(_code) => "FAIL",
+                    None => "OK",
+                };
+                let log = r
+                    .log_file
+                    .as_ref()
+                    .map(|p| p.to_string_lossy().to_string())
+                    .unwrap_or_else(|| "<no log>".to_string());
+                println!(
+                    "[{status}] branch={} worktree={} log={}",
+                    r.branch,
+                    r.worktree_dir.display(),
+                    log
+                );
+            }
+        } else {
+            concurrent::run_concurrent_flow(
+                prompt,
+                cli.config_overrides,
+                codex_linux_sandbox_exe,
+                cli.automerge,
+                false,
+            )
+            .await?;
+        }
+        return Ok(());
+    }
+
+    if cli.best_of_n > 1 {
+        eprintln!("--best-of-n requires --concurrent <PROMPT>");
+        std::process::exit(2);
+    }
+
     match cli.subcommand {
         None => {
             let mut tui_cli = cli.interactive;

codex-rs/core/Cargo.toml

@@ -34,7 +34,6 @@ serde_json = "1"
 serde_bytes = "0.11"
 sha1 = "0.10.6"
 shlex = "1.3.0"
-similar = "2.7.0"
 strum_macros = "0.27.2"
 thiserror = "2.0.12"
 time = { version = "0.3", features = ["formatting", "local-offset", "macros"] }
@@ -46,7 +45,7 @@ tokio = { version = "1", features = [
     "signal",
 ] }
 tokio-util = "0.7.14"
-toml = "0.9.4"
+toml = "0.9.2"
 tracing = { version = "0.1.41", features = ["log"] }
 tree-sitter = "0.25.8"
 tree-sitter-bash = "0.25.0"

codex-rs/core/prompt.md

@@ -10,7 +10,7 @@ You MUST adhere to the following criteria when executing the task:
 - Showing user code and tool call details is allowed.
 - User instructions may overwrite the _CODING GUIDELINES_ section in this developer message.
 - Do not use \`ls -R\`, \`find\`, or \`grep\` - these are slow in large repos. Use \`rg\` and \`rg --files\`.
-- Use \`apply_patch\` to edit files: {"command":["apply_patch","*** Begin Patch\\n*** Update File: path/to/file.py\\n@@ def example():\\n- pass\\n+ return 123\\n*** End Patch"]}
+- Use \`apply_patch\` to edit files: {"cmd":["apply_patch","*** Begin Patch\\n*** Update File: path/to/file.py\\n@@ def example():\\n- pass\\n+ return 123\\n*** End Patch"]}
 - If completing the user's task requires writing or modifying files:
   - Your code and final answer should follow these _CODING GUIDELINES_:
     - Fix the problem at the root cause rather than applying surface-level patches, when possible.
@@ -40,16 +40,16 @@ You MUST adhere to the following criteria when executing the task:
 
 Your patch language is a stripped‑down, file‑oriented diff format designed to be easy to parse and safe to apply. You can think of it as a high‑level envelope:
 
-*** Begin Patch
+**_ Begin Patch
 [ one or more file sections ]
-*** End Patch
+_** End Patch
 
 Within that envelope, you get a sequence of file operations.
 You MUST include a header to specify the action you are taking.
 Each operation starts with one of three headers:
 
-*** Add File: <path> - create a new file. Every following line is a + line (the initial contents).
-*** Delete File: <path> - remove an existing file. Nothing follows.
+**_ Add File: <path> - create a new file. Every following line is a + line (the initial contents).
+_** Delete File: <path> - remove an existing file. Nothing follows.
 \*\*\* Update File: <path> - patch an existing file in place (optionally with a rename).
 
 May be immediately followed by \*\*\* Move to: <new path> if you want to rename the file.
@@ -63,28 +63,28 @@ Within a hunk each line starts with:
   At the end of a truncated hunk you can emit \*\*\* End of File.
 
 Patch := Begin { FileOp } End
-Begin := "*** Begin Patch" NEWLINE
-End := "*** End Patch" NEWLINE
+Begin := "**_ Begin Patch" NEWLINE
+End := "_** End Patch" NEWLINE
 FileOp := AddFile | DeleteFile | UpdateFile
-AddFile := "*** Add File: " path NEWLINE { "+" line NEWLINE }
-DeleteFile := "*** Delete File: " path NEWLINE
-UpdateFile := "*** Update File: " path NEWLINE [ MoveTo ] { Hunk }
-MoveTo := "*** Move to: " newPath NEWLINE
+AddFile := "**_ Add File: " path NEWLINE { "+" line NEWLINE }
+DeleteFile := "_** Delete File: " path NEWLINE
+UpdateFile := "**_ Update File: " path NEWLINE [ MoveTo ] { Hunk }
+MoveTo := "_** Move to: " newPath NEWLINE
 Hunk := "@@" [ header ] NEWLINE { HunkLine } [ "*** End of File" NEWLINE ]
 HunkLine := (" " | "-" | "+") text NEWLINE
 
 A full patch can combine several operations:
 
-*** Begin Patch
-*** Add File: hello.txt
+**_ Begin Patch
+_** Add File: hello.txt
 +Hello world
-*** Update File: src/app.py
-*** Move to: src/main.py
+**_ Update File: src/app.py
+_** Move to: src/main.py
 @@ def greet():
 -print("Hi")
 +print("Hello, world!")
-*** Delete File: obsolete.txt
-*** End Patch
+**_ Delete File: obsolete.txt
+_** End Patch
 
 It is important to remember:
 
@@ -101,7 +101,7 @@ Plan updates
 
 A tool named `update_plan` is available. Use it to keep an up‑to‑date, step‑by‑step plan for the task so you can follow your progress. When making your plans, keep in mind that you are a deployed coding agent - `update_plan` calls should not involve doing anything that you aren't capable of doing. For example, `update_plan` calls should NEVER contain tasks to merge your own pull requests. Only stop to ask the user if you genuinely need their feedback on a change.
 
-- At the start of any nontrivial task, call `update_plan` with an initial plan: a short list of 1‑sentence steps with a `status` for each step (`pending`, `in_progress`, or `completed`). There should always be exactly one `in_progress` step until everything is done.
+- At the start of the task, call `update_plan` with an initial plan: a short list of 1‑sentence steps with a `status` for each step (`pending`, `in_progress`, or `completed`). There should always be exactly one `in_progress` step until everything is done.
 - Whenever you finish a step, call `update_plan` again, marking the finished step as `completed` and the next step as `in_progress`.
 - If your plan needs to change, call `update_plan` with the revised steps and include an `explanation` describing the change.
 - When all steps are complete, make a final `update_plan` call with all steps marked `completed`.

codex-rs/core/src/chat_completions.rs

@@ -207,7 +207,6 @@ async fn process_chat_sse<S>(
     }
 
     let mut fn_call_state = FunctionCallState::default();
-    let mut assistant_text = String::new();
 
     loop {
         let sse = match timeout(idle_timeout, stream.next()).await {
@@ -255,42 +254,21 @@ async fn process_chat_sse<S>(
         let choice_opt = chunk.get("choices").and_then(|c| c.get(0));
 
         if let Some(choice) = choice_opt {
-            // Handle assistant content tokens as streaming deltas.
+            // Handle assistant content tokens.
             if let Some(content) = choice
                 .get("delta")
                 .and_then(|d| d.get("content"))
                 .and_then(|c| c.as_str())
             {
-                if !content.is_empty() {
-                    assistant_text.push_str(content);
-                    let _ = tx_event
-                        .send(Ok(ResponseEvent::OutputTextDelta(content.to_string())))
-                        .await;
-                }
-            }
+                let item = ResponseItem::Message {
+                    role: "assistant".to_string(),
+                    content: vec![ContentItem::OutputText {
+                        text: content.to_string(),
+                    }],
+                    id: None,
+                };
 
-            // Forward any reasoning/thinking deltas if present.
-            if let Some(reasoning) = choice
-                .get("delta")
-                .and_then(|d| d.get("reasoning"))
-                .and_then(|c| c.as_str())
-            {
-                let _ = tx_event
-                    .send(Ok(ResponseEvent::ReasoningSummaryDelta(
-                        reasoning.to_string(),
-                    )))
-                    .await;
-            }
-            if let Some(reasoning_content) = choice
-                .get("delta")
-                .and_then(|d| d.get("reasoning_content"))
-                .and_then(|c| c.as_str())
-            {
-                let _ = tx_event
-                    .send(Ok(ResponseEvent::ReasoningSummaryDelta(
-                        reasoning_content.to_string(),
-                    )))
-                    .await;
+                let _ = tx_event.send(Ok(ResponseEvent::OutputItemDone(item))).await;
             }
 
             // Handle streaming function / tool calls.
@@ -339,18 +317,7 @@ async fn process_chat_sse<S>(
                         let _ = tx_event.send(Ok(ResponseEvent::OutputItemDone(item))).await;
                     }
                     "stop" => {
-                        // Regular turn without tool-call. Emit the final assistant message
-                        // as a single OutputItemDone so non-delta consumers see the result.
-                        if !assistant_text.is_empty() {
-                            let item = ResponseItem::Message {
-                                role: "assistant".to_string(),
-                                content: vec![ContentItem::OutputText {
-                                    text: std::mem::take(&mut assistant_text),
-                                }],
-                                id: None,
-                            };
-                            let _ = tx_event.send(Ok(ResponseEvent::OutputItemDone(item))).await;
-                        }
+                        // Regular turn without tool-call.
                     }
                     _ => {}
                 }
@@ -391,10 +358,7 @@ async fn process_chat_sse<S>(
 pub(crate) struct AggregatedChatStream<S> {
     inner: S,
     cumulative: String,
-    cumulative_reasoning: String,
-    pending: std::collections::VecDeque<ResponseEvent>,
-    // When true, do not emit a cumulative assistant message at Completed.
-    streaming_mode: bool,
+    pending_completed: Option<ResponseEvent>,
 }
 
 impl<S> Stream for AggregatedChatStream<S>
@@ -406,8 +370,8 @@ where
     fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
         let this = self.get_mut();
 
-        // First, flush any buffered events from the previous call.
-        if let Some(ev) = this.pending.pop_front() {
+        // First, flush any buffered Completed event from the previous call.
+        if let Some(ev) = this.pending_completed.take() {
             return Poll::Ready(Some(Ok(ev)));
         }
 
@@ -424,21 +388,16 @@ where
                     let is_assistant_delta = matches!(&item, crate::models::ResponseItem::Message { role, .. } if role == "assistant");
 
                     if is_assistant_delta {
-                        // Only use the final assistant message if we have not
-                        // seen any deltas; otherwise, deltas already built the
-                        // cumulative text and this would duplicate it.
-                        if this.cumulative.is_empty() {
-                            if let crate::models::ResponseItem::Message { content, .. } = &item {
-                                if let Some(text) = content.iter().find_map(|c| match c {
-                                    crate::models::ContentItem::OutputText { text } => Some(text),
-                                    _ => None,
-                                }) {
-                                    this.cumulative.push_str(text);
-                                }
+                        if let crate::models::ResponseItem::Message { content, .. } = &item {
+                            if let Some(text) = content.iter().find_map(|c| match c {
+                                crate::models::ContentItem::OutputText { text } => Some(text),
+                                _ => None,
+                            }) {
+                                this.cumulative.push_str(text);
                             }
                         }
 
-                        // Swallow assistant message here; emit on Completed.
+                        // Swallow partial assistant chunk; keep polling.
                         continue;
                     }
 
@@ -449,48 +408,24 @@ where
                     response_id,
                     token_usage,
                 }))) => {
-                    // Build any aggregated items in the correct order: Reasoning first, then Message.
-                    let mut emitted_any = false;
-
-                    if !this.cumulative_reasoning.is_empty() {
-                        let aggregated_reasoning = crate::models::ResponseItem::Reasoning {
-                            id: String::new(),
-                            summary: vec![
-                                crate::models::ReasoningItemReasoningSummary::SummaryText {
-                                    text: std::mem::take(&mut this.cumulative_reasoning),
-                                },
-                            ],
-                            content: None,
-                            encrypted_content: None,
-                        };
-                        this.pending
-                            .push_back(ResponseEvent::OutputItemDone(aggregated_reasoning));
-                        emitted_any = true;
-                    }
-
                     if !this.cumulative.is_empty() {
-                        let aggregated_message = crate::models::ResponseItem::Message {
+                        let aggregated_item = crate::models::ResponseItem::Message {
                             id: None,
                             role: "assistant".to_string(),
                             content: vec![crate::models::ContentItem::OutputText {
                                 text: std::mem::take(&mut this.cumulative),
                             }],
                         };
-                        this.pending
-                            .push_back(ResponseEvent::OutputItemDone(aggregated_message));
-                        emitted_any = true;
-                    }
 
-                    // Always emit Completed last when anything was aggregated.
-                    if emitted_any {
-                        this.pending.push_back(ResponseEvent::Completed {
-                            response_id: response_id.clone(),
-                            token_usage: token_usage.clone(),
+                        // Buffer Completed so it is returned *after* the aggregated message.
+                        this.pending_completed = Some(ResponseEvent::Completed {
+                            response_id,
+                            token_usage,
                         });
-                        // Return the first pending event now.
-                        if let Some(ev) = this.pending.pop_front() {
-                            return Poll::Ready(Some(Ok(ev)));
-                        }
+
+                        return Poll::Ready(Some(Ok(ResponseEvent::OutputItemDone(
+                            aggregated_item,
+                        ))));
                     }
 
                     // Nothing aggregated – forward Completed directly.
@@ -504,25 +439,11 @@ where
                     // will never appear in a Chat Completions stream.
                     continue;
                 }
-                Poll::Ready(Some(Ok(ResponseEvent::OutputTextDelta(delta)))) => {
-                    // Always accumulate deltas so we can emit a final OutputItemDone at Completed.
-                    this.cumulative.push_str(&delta);
-                    if this.streaming_mode {
-                        // In streaming mode, also forward the delta immediately.
-                        return Poll::Ready(Some(Ok(ResponseEvent::OutputTextDelta(delta))));
-                    } else {
-                        continue;
-                    }
-                }
-                Poll::Ready(Some(Ok(ResponseEvent::ReasoningSummaryDelta(delta)))) => {
-                    // Always accumulate reasoning deltas so we can emit a final Reasoning item at Completed.
-                    this.cumulative_reasoning.push_str(&delta);
-                    if this.streaming_mode {
-                        // In streaming mode, also forward the delta immediately.
-                        return Poll::Ready(Some(Ok(ResponseEvent::ReasoningSummaryDelta(delta))));
-                    } else {
-                        continue;
-                    }
+                Poll::Ready(Some(Ok(ResponseEvent::OutputTextDelta(_))))
+                | Poll::Ready(Some(Ok(ResponseEvent::ReasoningSummaryDelta(_)))) => {
+                    // Deltas are ignored here since aggregation waits for the
+                    // final OutputItemDone.
+                    continue;
                 }
             }
         }
@@ -554,23 +475,9 @@ pub(crate) trait AggregateStreamExt: Stream<Item = Result<ResponseEvent>> + Size
         AggregatedChatStream {
             inner: self,
             cumulative: String::new(),
-            cumulative_reasoning: String::new(),
-            pending: std::collections::VecDeque::new(),
-            streaming_mode: false,
+            pending_completed: None,
         }
     }
 }
 
 impl<T> AggregateStreamExt for T where T: Stream<Item = Result<ResponseEvent>> + Sized {}
-
-impl<S> AggregatedChatStream<S> {
-    pub(crate) fn streaming_mode(inner: S) -> Self {
-        AggregatedChatStream {
-            inner,
-            cumulative: String::new(),
-            cumulative_reasoning: String::new(),
-            pending: std::collections::VecDeque::new(),
-            streaming_mode: true,
-        }
-    }
-}

codex-rs/core/src/client.rs

@@ -93,11 +93,7 @@ impl ModelClient {
                 // Wrap it with the aggregation adapter so callers see *only*
                 // the final assistant message per turn (matching the
                 // behaviour of the Responses API).
-                let mut aggregated = if !self.config.hide_agent_reasoning {
-                    crate::chat_completions::AggregatedChatStream::streaming_mode(response_stream)
-                } else {
-                    response_stream.aggregate()
-                };
+                let mut aggregated = response_stream.aggregate();
 
                 // Bridge the aggregated stream back into a standard
                 // `ResponseStream` by forwarding events through a channel.
@@ -442,7 +438,7 @@ async fn process_sse<S>(
                     }
                 }
             }
-            "response.reasoning_summary_text.delta" | "response.reasoning_text.delta" => {
+            "response.reasoning_summary_text.delta" => {
                 if let Some(delta) = event.delta {
                     let event = ResponseEvent::ReasoningSummaryDelta(delta);
                     if tx_event.send(Ok(event)).await.is_err() {

codex-rs/core/src/codex.rs

@@ -56,7 +56,6 @@ use crate::mcp_tool_call::handle_mcp_tool_call;
 use crate::models::ContentItem;
 use crate::models::FunctionCallOutputPayload;
 use crate::models::LocalShellAction;
-use crate::models::ReasoningItemContent;
 use crate::models::ReasoningItemReasoningSummary;
 use crate::models::ResponseInputItem;
 use crate::models::ResponseItem;
@@ -65,7 +64,6 @@ use crate::plan_tool::handle_update_plan;
 use crate::project_doc::get_user_instructions;
 use crate::protocol::AgentMessageDeltaEvent;
 use crate::protocol::AgentMessageEvent;
-use crate::protocol::AgentReasoningContentEvent;
 use crate::protocol::AgentReasoningDeltaEvent;
 use crate::protocol::AgentReasoningEvent;
 use crate::protocol::ApplyPatchApprovalRequestEvent;
@@ -87,13 +85,11 @@ use crate::protocol::SandboxPolicy;
 use crate::protocol::SessionConfiguredEvent;
 use crate::protocol::Submission;
 use crate::protocol::TaskCompleteEvent;
-use crate::protocol::TurnDiffEvent;
 use crate::rollout::RolloutRecorder;
 use crate::safety::SafetyCheck;
 use crate::safety::assess_command_safety;
 use crate::safety::assess_safety_for_untrusted_command;
 use crate::shell;
-use crate::turn_diff_tracker::TurnDiffTracker;
 use crate::user_notification::UserNotification;
 use crate::util::backoff;
 
@@ -229,7 +225,6 @@ pub(crate) struct Session {
     state: Mutex<State>,
     codex_linux_sandbox_exe: Option<PathBuf>,
     user_shell: shell::Shell,
-    hide_agent_reasoning: bool,
 }
 
 impl Session {
@@ -367,11 +362,7 @@ impl Session {
         }
     }
 
-    async fn on_exec_command_begin(
-        &self,
-        turn_diff_tracker: &mut TurnDiffTracker,
-        exec_command_context: ExecCommandContext,
-    ) {
+    async fn notify_exec_command_begin(&self, exec_command_context: ExecCommandContext) {
         let ExecCommandContext {
             sub_id,
             call_id,
@@ -383,15 +374,11 @@ impl Session {
             Some(ApplyPatchCommandContext {
                 user_explicitly_approved_this_action,
                 changes,
-            }) => {
-                turn_diff_tracker.on_patch_begin(&changes);
-
-                EventMsg::PatchApplyBegin(PatchApplyBeginEvent {
-                    call_id,
-                    auto_approved: !user_explicitly_approved_this_action,
-                    changes,
-                })
-            }
+            }) => EventMsg::PatchApplyBegin(PatchApplyBeginEvent {
+                call_id,
+                auto_approved: !user_explicitly_approved_this_action,
+                changes,
+            }),
             None => EventMsg::ExecCommandBegin(ExecCommandBeginEvent {
                 call_id,
                 command: command_for_display.clone(),
@@ -405,21 +392,15 @@ impl Session {
         let _ = self.tx_event.send(event).await;
     }
 
-    #[allow(clippy::too_many_arguments)]
-    async fn on_exec_command_end(
+    async fn notify_exec_command_end(
         &self,
-        turn_diff_tracker: &mut TurnDiffTracker,
         sub_id: &str,
         call_id: &str,
-        output: &ExecToolCallOutput,
+        stdout: &str,
+        stderr: &str,
+        exit_code: i32,
         is_apply_patch: bool,
     ) {
-        let ExecToolCallOutput {
-            stdout,
-            stderr,
-            duration,
-            exit_code,
-        } = output;
         // Because stdout and stderr could each be up to 100 KiB, we send
         // truncated versions.
         const MAX_STREAM_OUTPUT: usize = 5 * 1024; // 5KiB
@@ -431,15 +412,14 @@ impl Session {
                 call_id: call_id.to_string(),
                 stdout,
                 stderr,
-                success: *exit_code == 0,
+                success: exit_code == 0,
             })
         } else {
             EventMsg::ExecCommandEnd(ExecCommandEndEvent {
                 call_id: call_id.to_string(),
                 stdout,
                 stderr,
-                duration: *duration,
-                exit_code: *exit_code,
+                exit_code,
             })
         };
 
@@ -448,20 +428,6 @@ impl Session {
             msg,
         };
         let _ = self.tx_event.send(event).await;
-
-        // If this is an apply_patch, after we emit the end patch, emit a second event
-        // with the full turn diff if there is one.
-        if is_apply_patch {
-            let unified_diff = turn_diff_tracker.get_unified_diff();
-            if let Ok(Some(unified_diff)) = unified_diff {
-                let msg = EventMsg::TurnDiff(TurnDiffEvent { unified_diff });
-                let event = Event {
-                    id: sub_id.into(),
-                    msg,
-                };
-                let _ = self.tx_event.send(event).await;
-            }
-        }
     }
 
     /// Helper that emits a BackgroundEvent with the given message. This keeps
@@ -825,7 +791,6 @@ async fn submission_loop(
                     codex_linux_sandbox_exe: config.codex_linux_sandbox_exe.clone(),
                     disable_response_storage,
                     user_shell: default_shell,
-                    hide_agent_reasoning: config.hide_agent_reasoning,
                 }));
 
                 // Patch restored state into the newly created session.
@@ -1036,10 +1001,6 @@ async fn run_task(sess: Arc<Session>, sub_id: String, input: Vec<InputItem>) {
         .await;
 
     let last_agent_message: Option<String>;
-    // Although from the perspective of codex.rs, TurnDiffTracker has the lifecycle of a Task which contains
-    // many turns, from the perspective of the user, it is a single turn.
-    let mut turn_diff_tracker = TurnDiffTracker::new();
-
     loop {
         // Note that pending_input would be something like a message the user
         // submitted through the UI while the model was running. Though the UI
@@ -1071,7 +1032,7 @@ async fn run_task(sess: Arc<Session>, sub_id: String, input: Vec<InputItem>) {
                 })
             })
             .collect();
-        match run_turn(&sess, &mut turn_diff_tracker, sub_id.clone(), turn_input).await {
+        match run_turn(&sess, sub_id.clone(), turn_input).await {
             Ok(turn_output) => {
                 let mut items_to_record_in_conversation_history = Vec::<ResponseItem>::new();
                 let mut responses = Vec::<ResponseInputItem>::new();
@@ -1136,7 +1097,6 @@ async fn run_task(sess: Arc<Session>, sub_id: String, input: Vec<InputItem>) {
                             ResponseItem::Reasoning {
                                 id,
                                 summary,
-                                content,
                                 encrypted_content,
                             },
                             None,
@@ -1144,7 +1104,6 @@ async fn run_task(sess: Arc<Session>, sub_id: String, input: Vec<InputItem>) {
                             items_to_record_in_conversation_history.push(ResponseItem::Reasoning {
                                 id: id.clone(),
                                 summary: summary.clone(),
-                                content: content.clone(),
                                 encrypted_content: encrypted_content.clone(),
                             });
                         }
@@ -1199,7 +1158,6 @@ async fn run_task(sess: Arc<Session>, sub_id: String, input: Vec<InputItem>) {
 
 async fn run_turn(
     sess: &Session,
-    turn_diff_tracker: &mut TurnDiffTracker,
     sub_id: String,
     input: Vec<ResponseItem>,
 ) -> CodexResult<Vec<ProcessedResponseItem>> {
@@ -1214,7 +1172,7 @@ async fn run_turn(
 
     let mut retries = 0;
     loop {
-        match try_run_turn(sess, turn_diff_tracker, &sub_id, &prompt).await {
+        match try_run_turn(sess, &sub_id, &prompt).await {
             Ok(output) => return Ok(output),
             Err(CodexErr::Interrupted) => return Err(CodexErr::Interrupted),
             Err(CodexErr::EnvVar(var)) => return Err(CodexErr::EnvVar(var)),
@@ -1260,7 +1218,6 @@ struct ProcessedResponseItem {
 
 async fn try_run_turn(
     sess: &Session,
-    turn_diff_tracker: &mut TurnDiffTracker,
     sub_id: &str,
     prompt: &Prompt,
 ) -> CodexResult<Vec<ProcessedResponseItem>> {
@@ -1348,8 +1305,7 @@ async fn try_run_turn(
         match event {
             ResponseEvent::Created => {}
             ResponseEvent::OutputItemDone(item) => {
-                let response =
-                    handle_response_item(sess, turn_diff_tracker, sub_id, item.clone()).await?;
+                let response = handle_response_item(sess, sub_id, item.clone()).await?;
 
                 output.push(ProcessedResponseItem { item, response });
             }
@@ -1367,16 +1323,6 @@ async fn try_run_turn(
                         .ok();
                 }
 
-                let unified_diff = turn_diff_tracker.get_unified_diff();
-                if let Ok(Some(unified_diff)) = unified_diff {
-                    let msg = EventMsg::TurnDiff(TurnDiffEvent { unified_diff });
-                    let event = Event {
-                        id: sub_id.to_string(),
-                        msg,
-                    };
-                    let _ = sess.tx_event.send(event).await;
-                }
-
                 return Ok(output);
             }
             ResponseEvent::OutputTextDelta(delta) => {
@@ -1387,13 +1333,11 @@ async fn try_run_turn(
                 sess.tx_event.send(event).await.ok();
             }
             ResponseEvent::ReasoningSummaryDelta(delta) => {
-                if !sess.hide_agent_reasoning {
-                    let event = Event {
-                        id: sub_id.to_string(),
-                        msg: EventMsg::AgentReasoningDelta(AgentReasoningDeltaEvent { delta }),
-                    };
-                    sess.tx_event.send(event).await.ok();
-                }
+                let event = Event {
+                    id: sub_id.to_string(),
+                    msg: EventMsg::AgentReasoningDelta(AgentReasoningDeltaEvent { delta }),
+                };
+                sess.tx_event.send(event).await.ok();
             }
         }
     }
@@ -1483,7 +1427,6 @@ async fn run_compact_task(
 
 async fn handle_response_item(
     sess: &Session,
-    turn_diff_tracker: &mut TurnDiffTracker,
     sub_id: &str,
     item: ResponseItem,
 ) -> CodexResult<Option<ResponseInputItem>> {
@@ -1501,36 +1444,16 @@ async fn handle_response_item(
             }
             None
         }
-        ResponseItem::Reasoning {
-            id: _,
-            summary,
-            content,
-            encrypted_content: _,
-        } => {
-            if !sess.hide_agent_reasoning {
-                for item in summary {
-                    let text = match item {
-                        ReasoningItemReasoningSummary::SummaryText { text } => text,
-                    };
-                    let event = Event {
-                        id: sub_id.to_string(),
-                        msg: EventMsg::AgentReasoning(AgentReasoningEvent { text }),
-                    };
-                    sess.tx_event.send(event).await.ok();
-                }
-            }
-            if !sess.hide_agent_reasoning && content.is_some() {
-                let content = content.unwrap();
-                for item in content {
-                    let text = match item {
-                        ReasoningItemContent::ReasoningText { text } => text,
-                    };
-                    let event = Event {
-                        id: sub_id.to_string(),
-                        msg: EventMsg::AgentReasoningContent(AgentReasoningContentEvent { text }),
-                    };
-                    sess.tx_event.send(event).await.ok();
-                }
+        ResponseItem::Reasoning { summary, .. } => {
+            for item in summary {
+                let text = match item {
+                    ReasoningItemReasoningSummary::SummaryText { text } => text,
+                };
+                let event = Event {
+                    id: sub_id.to_string(),
+                    msg: EventMsg::AgentReasoning(AgentReasoningEvent { text }),
+                };
+                sess.tx_event.send(event).await.ok();
             }
             None
         }
@@ -1541,17 +1464,7 @@ async fn handle_response_item(
             ..
         } => {
             info!("FunctionCall: {arguments}");
-            Some(
-                handle_function_call(
-                    sess,
-                    turn_diff_tracker,
-                    sub_id.to_string(),
-                    name,
-                    arguments,
-                    call_id,
-                )
-                .await,
-            )
+            Some(handle_function_call(sess, sub_id.to_string(), name, arguments, call_id).await)
         }
         ResponseItem::LocalShellCall {
             id,
@@ -1586,7 +1499,6 @@ async fn handle_response_item(
                 handle_container_exec_with_params(
                     exec_params,
                     sess,
-                    turn_diff_tracker,
                     sub_id.to_string(),
                     effective_call_id,
                 )
@@ -1604,7 +1516,6 @@ async fn handle_response_item(
 
 async fn handle_function_call(
     sess: &Session,
-    turn_diff_tracker: &mut TurnDiffTracker,
     sub_id: String,
     name: String,
     arguments: String,
@@ -1618,8 +1529,7 @@ async fn handle_function_call(
                     return *output;
                 }
             };
-            handle_container_exec_with_params(params, sess, turn_diff_tracker, sub_id, call_id)
-                .await
+            handle_container_exec_with_params(params, sess, sub_id, call_id).await
         }
         "update_plan" => handle_update_plan(sess, arguments, sub_id, call_id).await,
         _ => {
@@ -1693,7 +1603,6 @@ fn maybe_run_with_user_profile(params: ExecParams, sess: &Session) -> ExecParams
 async fn handle_container_exec_with_params(
     params: ExecParams,
     sess: &Session,
-    turn_diff_tracker: &mut TurnDiffTracker,
     sub_id: String,
     call_id: String,
 ) -> ResponseInputItem {
@@ -1841,7 +1750,7 @@ async fn handle_container_exec_with_params(
             },
         ),
     };
-    sess.on_exec_command_begin(turn_diff_tracker, exec_command_context.clone())
+    sess.notify_exec_command_begin(exec_command_context.clone())
         .await;
 
     let params = maybe_run_with_user_profile(params, sess);
@@ -1866,22 +1775,23 @@ async fn handle_container_exec_with_params(
                 stdout,
                 stderr,
                 duration,
-            } = &output;
+            } = output;
 
-            sess.on_exec_command_end(
-                turn_diff_tracker,
+            sess.notify_exec_command_end(
                 &sub_id,
                 &call_id,
-                &output,
+                &stdout,
+                &stderr,
+                exit_code,
                 exec_command_context.apply_patch.is_some(),
             )
             .await;
 
-            let is_success = *exit_code == 0;
+            let is_success = exit_code == 0;
             let content = format_exec_output(
-                if is_success { stdout } else { stderr },
-                *exit_code,
-                *duration,
+                if is_success { &stdout } else { &stderr },
+                exit_code,
+                duration,
             );
 
             ResponseInputItem::FunctionCallOutput {
@@ -1893,15 +1803,7 @@ async fn handle_container_exec_with_params(
             }
         }
         Err(CodexErr::Sandbox(error)) => {
-            handle_sandbox_error(
-                turn_diff_tracker,
-                params,
-                exec_command_context,
-                error,
-                sandbox_type,
-                sess,
-            )
-            .await
+            handle_sandbox_error(params, exec_command_context, error, sandbox_type, sess).await
         }
         Err(e) => {
             // Handle non-sandbox errors
@@ -1917,7 +1819,6 @@ async fn handle_container_exec_with_params(
 }
 
 async fn handle_sandbox_error(
-    turn_diff_tracker: &mut TurnDiffTracker,
     params: ExecParams,
     exec_command_context: ExecCommandContext,
     error: SandboxErr,
@@ -1974,8 +1875,7 @@ async fn handle_sandbox_error(
             sess.notify_background_event(&sub_id, "retrying command without sandbox")
                 .await;
 
-            sess.on_exec_command_begin(turn_diff_tracker, exec_command_context)
-                .await;
+            sess.notify_exec_command_begin(exec_command_context).await;
 
             // This is an escalated retry; the policy will not be
             // examined and the sandbox has been set to `None`.
@@ -2000,22 +1900,23 @@ async fn handle_sandbox_error(
                         stdout,
                         stderr,
                         duration,
-                    } = &retry_output;
+                    } = retry_output;
 
-                    sess.on_exec_command_end(
-                        turn_diff_tracker,
+                    sess.notify_exec_command_end(
                         &sub_id,
                         &call_id,
-                        &retry_output,
+                        &stdout,
+                        &stderr,
+                        exit_code,
                         is_apply_patch,
                     )
                     .await;
 
-                    let is_success = *exit_code == 0;
+                    let is_success = exit_code == 0;
                     let content = format_exec_output(
-                        if is_success { stdout } else { stderr },
-                        *exit_code,
-                        *duration,
+                        if is_success { &stdout } else { &stderr },
+                        exit_code,
+                        duration,
                     );
 
                     ResponseInputItem::FunctionCallOutput {

codex-rs/core/src/config.rs

@@ -480,18 +480,12 @@ impl Config {
         // Load base instructions override from a file if specified. If the
         // path is relative, resolve it against the effective cwd so the
         // behaviour matches other path-like config values.
-        let experimental_instructions_path = config_profile
-            .experimental_instructions_file
-            .as_ref()
-            .or(cfg.experimental_instructions_file.as_ref());
-        let file_base_instructions =
-            Self::get_base_instructions(experimental_instructions_path, &resolved_cwd)?;
+        let file_base_instructions = Self::get_base_instructions(
+            cfg.experimental_instructions_file.as_ref(),
+            &resolved_cwd,
+        )?;
         let base_instructions = base_instructions.or(file_base_instructions);
 
-        // Resolve hide/show reasoning flags with consistent precedence:
-        // if hide is true, force show_reasoning_content to false.
-        let hide_agent_reasoning_val = cfg.hide_agent_reasoning.unwrap_or(false);
-
         let config = Self {
             model,
             model_context_window,
@@ -521,7 +515,7 @@ impl Config {
             tui: cfg.tui.unwrap_or_default(),
             codex_linux_sandbox_exe,
 
-            hide_agent_reasoning: hide_agent_reasoning_val,
+            hide_agent_reasoning: cfg.hide_agent_reasoning.unwrap_or(false),
             model_reasoning_effort: config_profile
                 .model_reasoning_effort
                 .or(cfg.model_reasoning_effort)

codex-rs/core/src/config_profile.rs

@@ -1,5 +1,4 @@
 use serde::Deserialize;
-use std::path::PathBuf;
 
 use crate::config_types::ReasoningEffort;
 use crate::config_types::ReasoningSummary;
@@ -18,5 +17,4 @@ pub struct ConfigProfile {
     pub model_reasoning_effort: Option<ReasoningEffort>,
     pub model_reasoning_summary: Option<ReasoningSummary>,
     pub chatgpt_base_url: Option<String>,
-    pub experimental_instructions_file: Option<PathBuf>,
 }

codex-rs/core/src/exec.rs

@@ -140,7 +140,11 @@ pub async fn process_exec_tool_call(
 
             let exit_code = raw_output.exit_status.code().unwrap_or(-1);
 
-            if exit_code != 0 && is_likely_sandbox_denied(sandbox_type, exit_code) {
+            // NOTE(ragona): This is much less restrictive than the previous check. If we exec
+            // a command, and it returns anything other than success, we assume that it may have
+            // been a sandboxing error and allow the user to retry. (The user of course may choose
+            // not to retry, or in a non-interactive mode, would automatically reject the approval.)
+            if exit_code != 0 && sandbox_type != SandboxType::None {
                 return Err(CodexErr::Sandbox(SandboxErr::Denied(
                     exit_code, stdout, stderr,
                 )));
@@ -219,26 +223,6 @@ fn create_linux_sandbox_command_args(
     linux_cmd
 }
 
-/// We don't have a fully deterministic way to tell if our command failed
-/// because of the sandbox - a command in the user's zshrc file might hit an
-/// error, but the command itself might fail or succeed for other reasons.
-/// For now, we conservatively check for 'command not found' (exit code 127),
-/// and can add additional cases as necessary.
-fn is_likely_sandbox_denied(sandbox_type: SandboxType, exit_code: i32) -> bool {
-    if sandbox_type == SandboxType::None {
-        return false;
-    }
-
-    // Quick rejects: well-known non-sandbox shell exit codes
-    // 127: command not found, 2: misuse of shell builtins
-    if exit_code == 127 {
-        return false;
-    }
-
-    // For all other cases, we assume the sandbox is the cause
-    true
-}
-
 #[derive(Debug)]
 pub struct RawExecToolCallOutput {
     pub exit_status: ExitStatus,

codex-rs/core/src/lib.rs

@@ -38,14 +38,12 @@ pub mod plan_tool;
 mod project_doc;
 pub mod protocol;
 mod rollout;
-pub(crate) mod safety;
+mod safety;
 pub mod seatbelt;
 pub mod shell;
 pub mod spawn;
-pub mod turn_diff_tracker;
 mod user_notification;
 pub mod util;
 
 pub use apply_patch::CODEX_APPLY_PATCH_ARG1;
 pub use client_common::model_supports_reasoning_summaries;
-pub use safety::get_platform_sandbox;

codex-rs/core/src/models.rs

@@ -45,8 +45,6 @@ pub enum ResponseItem {
     Reasoning {
         id: String,
         summary: Vec<ReasoningItemReasoningSummary>,
-        #[serde(default, skip_serializing_if = "Option::is_none")]
-        content: Option<Vec<ReasoningItemContent>>,
         encrypted_content: Option<String>,
     },
     LocalShellCall {
@@ -138,12 +136,6 @@ pub enum ReasoningItemReasoningSummary {
     SummaryText { text: String },
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
-#[serde(tag = "type", rename_all = "snake_case")]
-pub enum ReasoningItemContent {
-    ReasoningText { text: String },
-}
-
 impl From<Vec<InputItem>> for ResponseInputItem {
     fn from(items: Vec<InputItem>) -> Self {
         Self::Message {

codex-rs/core/src/protocol.rs

@@ -359,9 +359,6 @@ pub enum EventMsg {
     /// Agent reasoning delta event from agent.
     AgentReasoningDelta(AgentReasoningDeltaEvent),
 
-    /// Raw chain-of-thought from agent.
-    AgentReasoningContent(AgentReasoningContentEvent),
-
     /// Ack the client's configure message.
     SessionConfigured(SessionConfiguredEvent),
 
@@ -390,8 +387,6 @@ pub enum EventMsg {
     /// Notification that a patch application has finished.
     PatchApplyEnd(PatchApplyEndEvent),
 
-    TurnDiff(TurnDiffEvent),
-
     /// Response to GetHistoryEntryRequest.
     GetHistoryEntryResponse(GetHistoryEntryResponseEvent),
 
@@ -467,11 +462,6 @@ pub struct AgentReasoningEvent {
     pub text: String,
 }
 
-#[derive(Debug, Clone, Deserialize, Serialize)]
-pub struct AgentReasoningContentEvent {
-    pub text: String,
-}
-
 #[derive(Debug, Clone, Deserialize, Serialize)]
 pub struct AgentReasoningDeltaEvent {
     pub delta: String,
@@ -533,8 +523,6 @@ pub struct ExecCommandEndEvent {
     pub stderr: String,
     /// The command's exit code.
     pub exit_code: i32,
-    /// The duration of the command execution.
-    pub duration: Duration,
 }
 
 #[derive(Debug, Clone, Deserialize, Serialize)]
@@ -608,11 +596,6 @@ pub struct PatchApplyEndEvent {
     pub success: bool,
 }
 
-#[derive(Debug, Clone, Deserialize, Serialize)]
-pub struct TurnDiffEvent {
-    pub unified_diff: String,
-}
-
 #[derive(Debug, Clone, Deserialize, Serialize)]
 pub struct GetHistoryEntryResponseEvent {
     pub offset: usize,

codex-rs/core/src/seatbelt_base_policy.sbpl

@@ -65,7 +65,3 @@
   (sysctl-name "sysctl.proc_cputype")
   (sysctl-name-prefix "hw.perflevel")
 )
-
-; Added on top of Chrome profile
-; Needed for python multiprocessing on MacOS for the SemLock
-(allow ipc-posix-sem)

codex-rs/core/src/turn_diff_tracker.rs

@@ -1,887 +0,0 @@
-use std::collections::HashMap;
-use std::fs;
-use std::path::Path;
-use std::path::PathBuf;
-use std::process::Command;
-
-use anyhow::Context;
-use anyhow::Result;
-use anyhow::anyhow;
-use sha1::digest::Output;
-use uuid::Uuid;
-
-use crate::protocol::FileChange;
-
-const ZERO_OID: &str = "0000000000000000000000000000000000000000";
-const DEV_NULL: &str = "/dev/null";
-
-struct BaselineFileInfo {
-    path: PathBuf,
-    content: Vec<u8>,
-    mode: FileMode,
-    oid: String,
-}
-
-/// Tracks sets of changes to files and exposes the overall unified diff.
-/// Internally, the way this works is now:
-/// 1. Maintain an in-memory baseline snapshot of files when they are first seen.
-///    For new additions, do not create a baseline so that diffs are shown as proper additions (using /dev/null).
-/// 2. Keep a stable internal filename (uuid) per external path for rename tracking.
-/// 3. To compute the aggregated unified diff, compare each baseline snapshot to the current file on disk entirely in-memory
-///    using the `similar` crate and emit unified diffs with rewritten external paths.
-#[derive(Default)]
-pub struct TurnDiffTracker {
-    /// Map external path -> internal filename (uuid).
-    external_to_temp_name: HashMap<PathBuf, String>,
-    /// Internal filename -> baseline file info.
-    baseline_file_info: HashMap<String, BaselineFileInfo>,
-    /// Internal filename -> external path as of current accumulated state (after applying all changes).
-    /// This is where renames are tracked.
-    temp_name_to_current_path: HashMap<String, PathBuf>,
-    /// Cache of known git worktree roots to avoid repeated filesystem walks.
-    git_root_cache: Vec<PathBuf>,
-}
-
-impl TurnDiffTracker {
-    pub fn new() -> Self {
-        Self::default()
-    }
-
-    /// Front-run apply patch calls to track the starting contents of any modified files.
-    /// - Creates an in-memory baseline snapshot for files that already exist on disk when first seen.
-    /// - For additions, we intentionally do not create a baseline snapshot so that diffs are proper additions.
-    /// - Also updates internal mappings for move/rename events.
-    pub fn on_patch_begin(&mut self, changes: &HashMap<PathBuf, FileChange>) {
-        for (path, change) in changes.iter() {
-            // Ensure a stable internal filename exists for this external path.
-            if !self.external_to_temp_name.contains_key(path) {
-                let internal = Uuid::new_v4().to_string();
-                self.external_to_temp_name
-                    .insert(path.clone(), internal.clone());
-                self.temp_name_to_current_path
-                    .insert(internal.clone(), path.clone());
-
-                // If the file exists on disk now, snapshot as baseline; else leave missing to represent /dev/null.
-                let baseline_file_info = if path.exists() {
-                    let mode = file_mode_for_path(path);
-                    let mode_val = mode.unwrap_or(FileMode::Regular);
-                    let content = blob_bytes(path, &mode_val).unwrap_or_default();
-                    let oid = if mode == Some(FileMode::Symlink) {
-                        format!("{:x}", git_blob_sha1_hex_bytes(&content))
-                    } else {
-                        self.git_blob_oid_for_path(path)
-                            .unwrap_or_else(|| format!("{:x}", git_blob_sha1_hex_bytes(&content)))
-                    };
-                    Some(BaselineFileInfo {
-                        path: path.clone(),
-                        content,
-                        mode: mode_val,
-                        oid,
-                    })
-                } else {
-                    Some(BaselineFileInfo {
-                        path: path.clone(),
-                        content: vec![],
-                        mode: FileMode::Regular,
-                        oid: ZERO_OID.to_string(),
-                    })
-                };
-
-                if let Some(baseline_file_info) = baseline_file_info {
-                    self.baseline_file_info
-                        .insert(internal.clone(), baseline_file_info);
-                }
-            }
-
-            // Track rename/move in current mapping if provided in an Update.
-            if let FileChange::Update {
-                move_path: Some(dest),
-                ..
-            } = change
-            {
-                let uuid_filename = match self.external_to_temp_name.get(path) {
-                    Some(i) => i.clone(),
-                    None => {
-                        // This should be rare, but if we haven't mapped the source, create it with no baseline.
-                        let i = Uuid::new_v4().to_string();
-                        self.baseline_file_info.insert(
-                            i.clone(),
-                            BaselineFileInfo {
-                                path: path.clone(),
-                                content: vec![],
-                                mode: FileMode::Regular,
-                                oid: ZERO_OID.to_string(),
-                            },
-                        );
-                        i
-                    }
-                };
-                // Update current external mapping for temp file name.
-                self.temp_name_to_current_path
-                    .insert(uuid_filename.clone(), dest.clone());
-                // Update forward file_mapping: external current -> internal name.
-                self.external_to_temp_name.remove(path);
-                self.external_to_temp_name
-                    .insert(dest.clone(), uuid_filename);
-            };
-        }
-    }
-
-    fn get_path_for_internal(&self, internal: &str) -> Option<PathBuf> {
-        self.temp_name_to_current_path
-            .get(internal)
-            .cloned()
-            .or_else(|| {
-                self.baseline_file_info
-                    .get(internal)
-                    .map(|info| info.path.clone())
-            })
-    }
-
-    /// Find the git worktree root for a file/directory by walking up to the first ancestor containing a `.git` entry.
-    /// Uses a simple cache of known roots and avoids negative-result caching for simplicity.
-    fn find_git_root_cached(&mut self, start: &Path) -> Option<PathBuf> {
-        let dir = if start.is_dir() {
-            start
-        } else {
-            start.parent()?
-        };
-
-        // Fast path: if any cached root is an ancestor of this path, use it.
-        if let Some(root) = self
-            .git_root_cache
-            .iter()
-            .find(|r| dir.starts_with(r))
-            .cloned()
-        {
-            return Some(root);
-        }
-
-        // Walk up to find a `.git` marker.
-        let mut cur = dir.to_path_buf();
-        loop {
-            let git_marker = cur.join(".git");
-            if git_marker.is_dir() || git_marker.is_file() {
-                if !self.git_root_cache.iter().any(|r| r == &cur) {
-                    self.git_root_cache.push(cur.clone());
-                }
-                return Some(cur);
-            }
-
-            // On Windows, avoid walking above the drive or UNC share root.
-            #[cfg(windows)]
-            {
-                if is_windows_drive_or_unc_root(&cur) {
-                    return None;
-                }
-            }
-
-            if let Some(parent) = cur.parent() {
-                cur = parent.to_path_buf();
-            } else {
-                return None;
-            }
-        }
-    }
-
-    /// Return a display string for `path` relative to its git root if found, else absolute.
-    fn relative_to_git_root_str(&mut self, path: &Path) -> String {
-        let s = if let Some(root) = self.find_git_root_cached(path) {
-            if let Ok(rel) = path.strip_prefix(&root) {
-                rel.display().to_string()
-            } else {
-                path.display().to_string()
-            }
-        } else {
-            path.display().to_string()
-        };
-        s.replace('\\', "/")
-    }
-
-    /// Ask git to compute the blob SHA-1 for the file at `path` within its repository.
-    /// Returns None if no repository is found or git invocation fails.
-    fn git_blob_oid_for_path(&mut self, path: &Path) -> Option<String> {
-        let root = self.find_git_root_cached(path)?;
-        // Compute a path relative to the repo root for better portability across platforms.
-        let rel = path.strip_prefix(&root).unwrap_or(path);
-        let output = Command::new("git")
-            .arg("-C")
-            .arg(&root)
-            .arg("hash-object")
-            .arg("--")
-            .arg(rel)
-            .output()
-            .ok()?;
-        if !output.status.success() {
-            return None;
-        }
-        let s = String::from_utf8_lossy(&output.stdout).trim().to_string();
-        if s.len() == 40 { Some(s) } else { None }
-    }
-
-    /// Recompute the aggregated unified diff by comparing all of the in-memory snapshots that were
-    /// collected before the first time they were touched by apply_patch during this turn with
-    /// the current repo state.
-    pub fn get_unified_diff(&mut self) -> Result<Option<String>> {
-        let mut aggregated = String::new();
-
-        // Compute diffs per tracked internal file in a stable order by external path.
-        let mut baseline_file_names: Vec<String> =
-            self.baseline_file_info.keys().cloned().collect();
-        // Sort lexicographically by full repo-relative path to match git behavior.
-        baseline_file_names.sort_by_key(|internal| {
-            self.get_path_for_internal(internal)
-                .map(|p| self.relative_to_git_root_str(&p))
-                .unwrap_or_default()
-        });
-
-        for internal in baseline_file_names {
-            aggregated.push_str(self.get_file_diff(&internal).as_str());
-            if !aggregated.ends_with('\n') {
-                aggregated.push('\n');
-            }
-        }
-
-        if aggregated.trim().is_empty() {
-            Ok(None)
-        } else {
-            Ok(Some(aggregated))
-        }
-    }
-
-    fn get_file_diff(&mut self, internal_file_name: &str) -> String {
-        let mut aggregated = String::new();
-
-        // Snapshot lightweight fields only.
-        let (baseline_external_path, baseline_mode, left_oid) = {
-            if let Some(info) = self.baseline_file_info.get(internal_file_name) {
-                (info.path.clone(), info.mode, info.oid.clone())
-            } else {
-                (PathBuf::new(), FileMode::Regular, ZERO_OID.to_string())
-            }
-        };
-        let current_external_path = match self.get_path_for_internal(internal_file_name) {
-            Some(p) => p,
-            None => return aggregated,
-        };
-
-        let current_mode = file_mode_for_path(&current_external_path).unwrap_or(FileMode::Regular);
-        let right_bytes = blob_bytes(&current_external_path, &current_mode);
-
-        // Compute displays with &mut self before borrowing any baseline content.
-        let left_display = self.relative_to_git_root_str(&baseline_external_path);
-        let right_display = self.relative_to_git_root_str(&current_external_path);
-
-        // Compute right oid before borrowing baseline content.
-        let right_oid = if let Some(b) = right_bytes.as_ref() {
-            if current_mode == FileMode::Symlink {
-                format!("{:x}", git_blob_sha1_hex_bytes(b))
-            } else {
-                self.git_blob_oid_for_path(&current_external_path)
-                    .unwrap_or_else(|| format!("{:x}", git_blob_sha1_hex_bytes(b)))
-            }
-        } else {
-            ZERO_OID.to_string()
-        };
-
-        // Borrow baseline content only after all &mut self uses are done.
-        let left_present = left_oid.as_str() != ZERO_OID;
-        let left_bytes: Option<&[u8]> = if left_present {
-            self.baseline_file_info
-                .get(internal_file_name)
-                .map(|i| i.content.as_slice())
-        } else {
-            None
-        };
-
-        // Fast path: identical bytes or both missing.
-        if left_bytes == right_bytes.as_deref() {
-            return aggregated;
-        }
-
-        aggregated.push_str(&format!("diff --git a/{left_display} b/{right_display}\n"));
-
-        let is_add = !left_present && right_bytes.is_some();
-        let is_delete = left_present && right_bytes.is_none();
-
-        if is_add {
-            aggregated.push_str(&format!("new file mode {current_mode}\n"));
-        } else if is_delete {
-            aggregated.push_str(&format!("deleted file mode {baseline_mode}\n"));
-        } else if baseline_mode != current_mode {
-            aggregated.push_str(&format!("old mode {baseline_mode}\n"));
-            aggregated.push_str(&format!("new mode {current_mode}\n"));
-        }
-
-        let left_text = left_bytes.and_then(|b| std::str::from_utf8(b).ok());
-        let right_text = right_bytes
-            .as_deref()
-            .and_then(|b| std::str::from_utf8(b).ok());
-
-        let can_text_diff = matches!(
-            (left_text, right_text, is_add, is_delete),
-            (Some(_), Some(_), _, _) | (_, Some(_), true, _) | (Some(_), _, _, true)
-        );
-
-        if can_text_diff {
-            let l = left_text.unwrap_or("");
-            let r = right_text.unwrap_or("");
-
-            aggregated.push_str(&format!("index {left_oid}..{right_oid}\n"));
-
-            let old_header = if left_present {
-                format!("a/{left_display}")
-            } else {
-                DEV_NULL.to_string()
-            };
-            let new_header = if right_bytes.is_some() {
-                format!("b/{right_display}")
-            } else {
-                DEV_NULL.to_string()
-            };
-
-            let diff = similar::TextDiff::from_lines(l, r);
-            let unified = diff
-                .unified_diff()
-                .context_radius(3)
-                .header(&old_header, &new_header)
-                .to_string();
-
-            aggregated.push_str(&unified);
-        } else {
-            aggregated.push_str(&format!("index {left_oid}..{right_oid}\n"));
-            let old_header = if left_present {
-                format!("a/{left_display}")
-            } else {
-                DEV_NULL.to_string()
-            };
-            let new_header = if right_bytes.is_some() {
-                format!("b/{right_display}")
-            } else {
-                DEV_NULL.to_string()
-            };
-            aggregated.push_str(&format!("--- {old_header}\n"));
-            aggregated.push_str(&format!("+++ {new_header}\n"));
-            aggregated.push_str("Binary files differ\n");
-        }
-        aggregated
-    }
-}
-
-/// Compute the Git SHA-1 blob object ID for the given content (bytes).
-fn git_blob_sha1_hex_bytes(data: &[u8]) -> Output<sha1::Sha1> {
-    // Git blob hash is sha1 of: "blob <len>\0<data>"
-    let header = format!("blob {}\0", data.len());
-    use sha1::Digest;
-    let mut hasher = sha1::Sha1::new();
-    hasher.update(header.as_bytes());
-    hasher.update(data);
-    hasher.finalize()
-}
-
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-enum FileMode {
-    Regular,
-    #[cfg(unix)]
-    Executable,
-    Symlink,
-}
-
-impl FileMode {
-    fn as_str(&self) -> &'static str {
-        match self {
-            FileMode::Regular => "100644",
-            #[cfg(unix)]
-            FileMode::Executable => "100755",
-            FileMode::Symlink => "120000",
-        }
-    }
-}
-
-impl std::fmt::Display for FileMode {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.write_str(self.as_str())
-    }
-}
-
-#[cfg(unix)]
-fn file_mode_for_path(path: &Path) -> Option<FileMode> {
-    use std::os::unix::fs::PermissionsExt;
-    let meta = fs::symlink_metadata(path).ok()?;
-    let ft = meta.file_type();
-    if ft.is_symlink() {
-        return Some(FileMode::Symlink);
-    }
-    let mode = meta.permissions().mode();
-    let is_exec = (mode & 0o111) != 0;
-    Some(if is_exec {
-        FileMode::Executable
-    } else {
-        FileMode::Regular
-    })
-}
-
-#[cfg(not(unix))]
-fn file_mode_for_path(_path: &Path) -> Option<FileMode> {
-    // Default to non-executable on non-unix.
-    Some(FileMode::Regular)
-}
-
-fn blob_bytes(path: &Path, mode: &FileMode) -> Option<Vec<u8>> {
-    if path.exists() {
-        let contents = if *mode == FileMode::Symlink {
-            symlink_blob_bytes(path)
-                .ok_or_else(|| anyhow!("failed to read symlink target for {}", path.display()))
-        } else {
-            fs::read(path)
-                .with_context(|| format!("failed to read current file for diff {}", path.display()))
-        };
-        contents.ok()
-    } else {
-        None
-    }
-}
-
-#[cfg(unix)]
-fn symlink_blob_bytes(path: &Path) -> Option<Vec<u8>> {
-    use std::os::unix::ffi::OsStrExt;
-    let target = std::fs::read_link(path).ok()?;
-    Some(target.as_os_str().as_bytes().to_vec())
-}
-
-#[cfg(not(unix))]
-fn symlink_blob_bytes(_path: &Path) -> Option<Vec<u8>> {
-    None
-}
-
-#[cfg(windows)]
-fn is_windows_drive_or_unc_root(p: &std::path::Path) -> bool {
-    use std::path::Component;
-    let mut comps = p.components();
-    matches!(
-        (comps.next(), comps.next(), comps.next()),
-        (Some(Component::Prefix(_)), Some(Component::RootDir), None)
-    )
-}
-
-#[cfg(test)]
-mod tests {
-    #![allow(clippy::unwrap_used)]
-    use super::*;
-    use pretty_assertions::assert_eq;
-    use tempfile::tempdir;
-
-    /// Compute the Git SHA-1 blob object ID for the given content (string).
-    /// This delegates to the bytes version to avoid UTF-8 lossy conversions here.
-    fn git_blob_sha1_hex(data: &str) -> String {
-        format!("{:x}", git_blob_sha1_hex_bytes(data.as_bytes()))
-    }
-
-    fn normalize_diff_for_test(input: &str, root: &Path) -> String {
-        let root_str = root.display().to_string().replace('\\', "/");
-        let replaced = input.replace(&root_str, "<TMP>");
-        // Split into blocks on lines starting with "diff --git ", sort blocks for determinism, and rejoin
-        let mut blocks: Vec<String> = Vec::new();
-        let mut current = String::new();
-        for line in replaced.lines() {
-            if line.starts_with("diff --git ") && !current.is_empty() {
-                blocks.push(current);
-                current = String::new();
-            }
-            if !current.is_empty() {
-                current.push('\n');
-            }
-            current.push_str(line);
-        }
-        if !current.is_empty() {
-            blocks.push(current);
-        }
-        blocks.sort();
-        let mut out = blocks.join("\n");
-        if !out.ends_with('\n') {
-            out.push('\n');
-        }
-        out
-    }
-
-    #[test]
-    fn accumulates_add_and_update() {
-        let mut acc = TurnDiffTracker::new();
-
-        let dir = tempdir().unwrap();
-        let file = dir.path().join("a.txt");
-
-        // First patch: add file (baseline should be /dev/null).
-        let add_changes = HashMap::from([(
-            file.clone(),
-            FileChange::Add {
-                content: "foo\n".to_string(),
-            },
-        )]);
-        acc.on_patch_begin(&add_changes);
-
-        // Simulate apply: create the file on disk.
-        fs::write(&file, "foo\n").unwrap();
-        let first = acc.get_unified_diff().unwrap().unwrap();
-        let first = normalize_diff_for_test(&first, dir.path());
-        let expected_first = {
-            let mode = file_mode_for_path(&file).unwrap_or(FileMode::Regular);
-            let right_oid = git_blob_sha1_hex("foo\n");
-            format!(
-                r#"diff --git a/<TMP>/a.txt b/<TMP>/a.txt
-new file mode {mode}
-index {ZERO_OID}..{right_oid}
---- {DEV_NULL}
-+++ b/<TMP>/a.txt
-@@ -0,0 +1 @@
-+foo
-"#,
-            )
-        };
-        assert_eq!(first, expected_first);
-
-        // Second patch: update the file on disk.
-        let update_changes = HashMap::from([(
-            file.clone(),
-            FileChange::Update {
-                unified_diff: "".to_owned(),
-                move_path: None,
-            },
-        )]);
-        acc.on_patch_begin(&update_changes);
-
-        // Simulate apply: append a new line.
-        fs::write(&file, "foo\nbar\n").unwrap();
-        let combined = acc.get_unified_diff().unwrap().unwrap();
-        let combined = normalize_diff_for_test(&combined, dir.path());
-        let expected_combined = {
-            let mode = file_mode_for_path(&file).unwrap_or(FileMode::Regular);
-            let right_oid = git_blob_sha1_hex("foo\nbar\n");
-            format!(
-                r#"diff --git a/<TMP>/a.txt b/<TMP>/a.txt
-new file mode {mode}
-index {ZERO_OID}..{right_oid}
---- {DEV_NULL}
-+++ b/<TMP>/a.txt
-@@ -0,0 +1,2 @@
-+foo
-+bar
-"#,
-            )
-        };
-        assert_eq!(combined, expected_combined);
-    }
-
-    #[test]
-    fn accumulates_delete() {
-        let dir = tempdir().unwrap();
-        let file = dir.path().join("b.txt");
-        fs::write(&file, "x\n").unwrap();
-
-        let mut acc = TurnDiffTracker::new();
-        let del_changes = HashMap::from([(file.clone(), FileChange::Delete)]);
-        acc.on_patch_begin(&del_changes);
-
-        // Simulate apply: delete the file from disk.
-        let baseline_mode = file_mode_for_path(&file).unwrap_or(FileMode::Regular);
-        fs::remove_file(&file).unwrap();
-        let diff = acc.get_unified_diff().unwrap().unwrap();
-        let diff = normalize_diff_for_test(&diff, dir.path());
-        let expected = {
-            let left_oid = git_blob_sha1_hex("x\n");
-            format!(
-                r#"diff --git a/<TMP>/b.txt b/<TMP>/b.txt
-deleted file mode {baseline_mode}
-index {left_oid}..{ZERO_OID}
---- a/<TMP>/b.txt
-+++ {DEV_NULL}
-@@ -1 +0,0 @@
--x
-"#,
-            )
-        };
-        assert_eq!(diff, expected);
-    }
-
-    #[test]
-    fn accumulates_move_and_update() {
-        let dir = tempdir().unwrap();
-        let src = dir.path().join("src.txt");
-        let dest = dir.path().join("dst.txt");
-        fs::write(&src, "line\n").unwrap();
-
-        let mut acc = TurnDiffTracker::new();
-        let mv_changes = HashMap::from([(
-            src.clone(),
-            FileChange::Update {
-                unified_diff: "".to_owned(),
-                move_path: Some(dest.clone()),
-            },
-        )]);
-        acc.on_patch_begin(&mv_changes);
-
-        // Simulate apply: move and update content.
-        fs::rename(&src, &dest).unwrap();
-        fs::write(&dest, "line2\n").unwrap();
-
-        let out = acc.get_unified_diff().unwrap().unwrap();
-        let out = normalize_diff_for_test(&out, dir.path());
-        let expected = {
-            let left_oid = git_blob_sha1_hex("line\n");
-            let right_oid = git_blob_sha1_hex("line2\n");
-            format!(
-                r#"diff --git a/<TMP>/src.txt b/<TMP>/dst.txt
-index {left_oid}..{right_oid}
---- a/<TMP>/src.txt
-+++ b/<TMP>/dst.txt
-@@ -1 +1 @@
--line
-+line2
-"#
-            )
-        };
-        assert_eq!(out, expected);
-    }
-
-    #[test]
-    fn move_without_1change_yields_no_diff() {
-        let dir = tempdir().unwrap();
-        let src = dir.path().join("moved.txt");
-        let dest = dir.path().join("renamed.txt");
-        fs::write(&src, "same\n").unwrap();
-
-        let mut acc = TurnDiffTracker::new();
-        let mv_changes = HashMap::from([(
-            src.clone(),
-            FileChange::Update {
-                unified_diff: "".to_owned(),
-                move_path: Some(dest.clone()),
-            },
-        )]);
-        acc.on_patch_begin(&mv_changes);
-
-        // Simulate apply: move only, no content change.
-        fs::rename(&src, &dest).unwrap();
-
-        let diff = acc.get_unified_diff().unwrap();
-        assert_eq!(diff, None);
-    }
-
-    #[test]
-    fn move_declared_but_file_only_appears_at_dest_is_add() {
-        let dir = tempdir().unwrap();
-        let src = dir.path().join("src.txt");
-        let dest = dir.path().join("dest.txt");
-        let mut acc = TurnDiffTracker::new();
-        let mv = HashMap::from([(
-            src.clone(),
-            FileChange::Update {
-                unified_diff: "".into(),
-                move_path: Some(dest.clone()),
-            },
-        )]);
-        acc.on_patch_begin(&mv);
-        // No file existed initially; create only dest
-        fs::write(&dest, "hello\n").unwrap();
-        let diff = acc.get_unified_diff().unwrap().unwrap();
-        let diff = normalize_diff_for_test(&diff, dir.path());
-        let expected = {
-            let mode = file_mode_for_path(&dest).unwrap_or(FileMode::Regular);
-            let right_oid = git_blob_sha1_hex("hello\n");
-            format!(
-                r#"diff --git a/<TMP>/src.txt b/<TMP>/dest.txt
-new file mode {mode}
-index {ZERO_OID}..{right_oid}
---- {DEV_NULL}
-+++ b/<TMP>/dest.txt
-@@ -0,0 +1 @@
-+hello
-"#,
-            )
-        };
-        assert_eq!(diff, expected);
-    }
-
-    #[test]
-    fn update_persists_across_new_baseline_for_new_file() {
-        let dir = tempdir().unwrap();
-        let a = dir.path().join("a.txt");
-        let b = dir.path().join("b.txt");
-        fs::write(&a, "foo\n").unwrap();
-        fs::write(&b, "z\n").unwrap();
-
-        let mut acc = TurnDiffTracker::new();
-
-        // First: update existing a.txt (baseline snapshot is created for a).
-        let update_a = HashMap::from([(
-            a.clone(),
-            FileChange::Update {
-                unified_diff: "".to_owned(),
-                move_path: None,
-            },
-        )]);
-        acc.on_patch_begin(&update_a);
-        // Simulate apply: modify a.txt on disk.
-        fs::write(&a, "foo\nbar\n").unwrap();
-        let first = acc.get_unified_diff().unwrap().unwrap();
-        let first = normalize_diff_for_test(&first, dir.path());
-        let expected_first = {
-            let left_oid = git_blob_sha1_hex("foo\n");
-            let right_oid = git_blob_sha1_hex("foo\nbar\n");
-            format!(
-                r#"diff --git a/<TMP>/a.txt b/<TMP>/a.txt
-index {left_oid}..{right_oid}
---- a/<TMP>/a.txt
-+++ b/<TMP>/a.txt
-@@ -1 +1,2 @@
- foo
-+bar
-"#
-            )
-        };
-        assert_eq!(first, expected_first);
-
-        // Next: introduce a brand-new path b.txt into baseline snapshots via a delete change.
-        let del_b = HashMap::from([(b.clone(), FileChange::Delete)]);
-        acc.on_patch_begin(&del_b);
-        // Simulate apply: delete b.txt.
-        let baseline_mode = file_mode_for_path(&b).unwrap_or(FileMode::Regular);
-        fs::remove_file(&b).unwrap();
-
-        let combined = acc.get_unified_diff().unwrap().unwrap();
-        let combined = normalize_diff_for_test(&combined, dir.path());
-        let expected = {
-            let left_oid_a = git_blob_sha1_hex("foo\n");
-            let right_oid_a = git_blob_sha1_hex("foo\nbar\n");
-            let left_oid_b = git_blob_sha1_hex("z\n");
-            format!(
-                r#"diff --git a/<TMP>/a.txt b/<TMP>/a.txt
-index {left_oid_a}..{right_oid_a}
---- a/<TMP>/a.txt
-+++ b/<TMP>/a.txt
-@@ -1 +1,2 @@
- foo
-+bar
-diff --git a/<TMP>/b.txt b/<TMP>/b.txt
-deleted file mode {baseline_mode}
-index {left_oid_b}..{ZERO_OID}
---- a/<TMP>/b.txt
-+++ {DEV_NULL}
-@@ -1 +0,0 @@
--z
-"#,
-            )
-        };
-        assert_eq!(combined, expected);
-    }
-
-    #[test]
-    fn binary_files_differ_update() {
-        let dir = tempdir().unwrap();
-        let file = dir.path().join("bin.dat");
-
-        // Initial non-UTF8 bytes
-        let left_bytes: Vec<u8> = vec![0xff, 0xfe, 0xfd, 0x00];
-        // Updated non-UTF8 bytes
-        let right_bytes: Vec<u8> = vec![0x01, 0x02, 0x03, 0x00];
-
-        fs::write(&file, &left_bytes).unwrap();
-
-        let mut acc = TurnDiffTracker::new();
-        let update_changes = HashMap::from([(
-            file.clone(),
-            FileChange::Update {
-                unified_diff: "".to_owned(),
-                move_path: None,
-            },
-        )]);
-        acc.on_patch_begin(&update_changes);
-
-        // Apply update on disk
-        fs::write(&file, &right_bytes).unwrap();
-
-        let diff = acc.get_unified_diff().unwrap().unwrap();
-        let diff = normalize_diff_for_test(&diff, dir.path());
-        let expected = {
-            let left_oid = format!("{:x}", git_blob_sha1_hex_bytes(&left_bytes));
-            let right_oid = format!("{:x}", git_blob_sha1_hex_bytes(&right_bytes));
-            format!(
-                r#"diff --git a/<TMP>/bin.dat b/<TMP>/bin.dat
-index {left_oid}..{right_oid}
---- a/<TMP>/bin.dat
-+++ b/<TMP>/bin.dat
-Binary files differ
-"#
-            )
-        };
-        assert_eq!(diff, expected);
-    }
-
-    #[test]
-    fn filenames_with_spaces_add_and_update() {
-        let mut acc = TurnDiffTracker::new();
-
-        let dir = tempdir().unwrap();
-        let file = dir.path().join("name with spaces.txt");
-
-        // First patch: add file (baseline should be /dev/null).
-        let add_changes = HashMap::from([(
-            file.clone(),
-            FileChange::Add {
-                content: "foo\n".to_string(),
-            },
-        )]);
-        acc.on_patch_begin(&add_changes);
-
-        // Simulate apply: create the file on disk.
-        fs::write(&file, "foo\n").unwrap();
-        let first = acc.get_unified_diff().unwrap().unwrap();
-        let first = normalize_diff_for_test(&first, dir.path());
-        let expected_first = {
-            let mode = file_mode_for_path(&file).unwrap_or(FileMode::Regular);
-            let right_oid = git_blob_sha1_hex("foo\n");
-            format!(
-                r#"diff --git a/<TMP>/name with spaces.txt b/<TMP>/name with spaces.txt
-new file mode {mode}
-index {ZERO_OID}..{right_oid}
---- {DEV_NULL}
-+++ b/<TMP>/name with spaces.txt
-@@ -0,0 +1 @@
-+foo
-"#,
-            )
-        };
-        assert_eq!(first, expected_first);
-
-        // Second patch: update the file on disk.
-        let update_changes = HashMap::from([(
-            file.clone(),
-            FileChange::Update {
-                unified_diff: "".to_owned(),
-                move_path: None,
-            },
-        )]);
-        acc.on_patch_begin(&update_changes);
-
-        // Simulate apply: append a new line with a space.
-        fs::write(&file, "foo\nbar baz\n").unwrap();
-        let combined = acc.get_unified_diff().unwrap().unwrap();
-        let combined = normalize_diff_for_test(&combined, dir.path());
-        let expected_combined = {
-            let mode = file_mode_for_path(&file).unwrap_or(FileMode::Regular);
-            let right_oid = git_blob_sha1_hex("foo\nbar baz\n");
-            format!(
-                r#"diff --git a/<TMP>/name with spaces.txt b/<TMP>/name with spaces.txt
-new file mode {mode}
-index {ZERO_OID}..{right_oid}
---- {DEV_NULL}
-+++ b/<TMP>/name with spaces.txt
-@@ -0,0 +1,2 @@
-+foo
-+bar baz
-"#,
-            )
-        };
-        assert_eq!(combined, expected_combined);
-    }
-}

codex-rs/core/tests/exec.rs

@@ -1,69 +0,0 @@
-#![cfg(target_os = "macos")]
-#![expect(clippy::expect_used)]
-
-use std::collections::HashMap;
-use std::sync::Arc;
-
-use codex_core::exec::ExecParams;
-use codex_core::exec::SandboxType;
-use codex_core::exec::process_exec_tool_call;
-use codex_core::protocol::SandboxPolicy;
-use codex_core::spawn::CODEX_SANDBOX_ENV_VAR;
-use tempfile::TempDir;
-use tokio::sync::Notify;
-
-use codex_core::get_platform_sandbox;
-
-async fn run_test_cmd(tmp: TempDir, cmd: Vec<&str>, should_be_ok: bool) {
-    if std::env::var(CODEX_SANDBOX_ENV_VAR) == Ok("seatbelt".to_string()) {
-        eprintln!("{CODEX_SANDBOX_ENV_VAR} is set to 'seatbelt', skipping test.");
-        return;
-    }
-
-    let sandbox_type = get_platform_sandbox().expect("should be able to get sandbox type");
-    assert_eq!(sandbox_type, SandboxType::MacosSeatbelt);
-
-    let params = ExecParams {
-        command: cmd.iter().map(|s| s.to_string()).collect(),
-        cwd: tmp.path().to_path_buf(),
-        timeout_ms: Some(1000),
-        env: HashMap::new(),
-    };
-
-    let ctrl_c = Arc::new(Notify::new());
-    let policy = SandboxPolicy::new_read_only_policy();
-
-    let result = process_exec_tool_call(params, sandbox_type, ctrl_c, &policy, &None, None).await;
-
-    assert!(result.is_ok() == should_be_ok);
-}
-
-/// Command succeeds with exit code 0 normally
-#[tokio::test]
-async fn exit_code_0_succeeds() {
-    let tmp = TempDir::new().expect("should be able to create temp dir");
-    let cmd = vec!["echo", "hello"];
-
-    run_test_cmd(tmp, cmd, true).await
-}
-
-/// Command not found returns exit code 127, this is not considered a sandbox error
-#[tokio::test]
-async fn exit_command_not_found_is_ok() {
-    let tmp = TempDir::new().expect("should be able to create temp dir");
-    let cmd = vec!["/bin/bash", "-c", "nonexistent_command_12345"];
-    run_test_cmd(tmp, cmd, true).await
-}
-
-/// Writing a file fails and should be considered a sandbox error
-#[tokio::test]
-async fn write_file_fails_as_sandbox_error() {
-    let tmp = TempDir::new().expect("should be able to create temp dir");
-    let path = tmp.path().join("test.txt");
-    let cmd = vec![
-        "/user/bin/touch",
-        path.to_str().expect("should be able to get path"),
-    ];
-
-    run_test_cmd(tmp, cmd, false).await;
-}

codex-rs/core/tests/live_agent.rs

@@ -177,7 +177,8 @@ async fn live_shell_function_call() {
         match ev.msg {
             EventMsg::ExecCommandBegin(codex_core::protocol::ExecCommandBeginEvent {
                 command,
-                ..
+                call_id: _,
+                cwd: _,
             }) => {
                 assert_eq!(command, vec!["echo", MARKER]);
                 saw_begin = true;
@@ -185,7 +186,8 @@ async fn live_shell_function_call() {
             EventMsg::ExecCommandEnd(codex_core::protocol::ExecCommandEndEvent {
                 stdout,
                 exit_code,
-                ..
+                call_id: _,
+                stderr: _,
             }) => {
                 assert_eq!(exit_code, 0, "echo returned non‑zero exit code");
                 assert!(stdout.contains(MARKER));

codex-rs/exec/src/event_processor.rs

@@ -44,14 +44,20 @@ pub(crate) fn create_config_summary_entries(config: &Config) -> Vec<(&'static st
     entries
 }
 
-pub(crate) fn handle_last_message(last_agent_message: Option<&str>, output_file: &Path) {
-    let message = last_agent_message.unwrap_or_default();
-    write_last_message_file(message, Some(output_file));
-    if last_agent_message.is_none() {
-        eprintln!(
-            "Warning: no last agent message; wrote empty content to {}",
-            output_file.display()
-        );
+pub(crate) fn handle_last_message(
+    last_agent_message: Option<&str>,
+    last_message_path: Option<&Path>,
+) {
+    match (last_message_path, last_agent_message) {
+        (Some(path), Some(msg)) => write_last_message_file(msg, Some(path)),
+        (Some(path), None) => {
+            write_last_message_file("", Some(path));
+            eprintln!(
+                "Warning: no last agent message; wrote empty content to {}",
+                path.display()
+            );
+        }
+        (None, _) => eprintln!("Warning: no file to write last message to."),
     }
 }
 

codex-rs/exec/src/event_processor_with_human_output.rs

@@ -4,7 +4,6 @@ use codex_core::config::Config;
 use codex_core::plan_tool::UpdatePlanArgs;
 use codex_core::protocol::AgentMessageDeltaEvent;
 use codex_core::protocol::AgentMessageEvent;
-use codex_core::protocol::AgentReasoningContentEvent;
 use codex_core::protocol::AgentReasoningDeltaEvent;
 use codex_core::protocol::BackgroundEventEvent;
 use codex_core::protocol::ErrorEvent;
@@ -21,7 +20,6 @@ use codex_core::protocol::PatchApplyEndEvent;
 use codex_core::protocol::SessionConfiguredEvent;
 use codex_core::protocol::TaskCompleteEvent;
 use codex_core::protocol::TokenUsage;
-use codex_core::protocol::TurnDiffEvent;
 use owo_colors::OwoColorize;
 use owo_colors::Style;
 use shlex::try_join;
@@ -108,6 +106,7 @@ impl EventProcessorWithHumanOutput {
 
 struct ExecCommandBegin {
     command: Vec<String>,
+    start_time: Instant,
 }
 
 struct PatchApplyBegin {
@@ -171,9 +170,10 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                 // Ignore.
             }
             EventMsg::TaskComplete(TaskCompleteEvent { last_agent_message }) => {
-                if let Some(output_file) = self.last_message_path.as_deref() {
-                    handle_last_message(last_agent_message.as_deref(), output_file);
-                }
+                handle_last_message(
+                    last_agent_message.as_deref(),
+                    self.last_message_path.as_deref(),
+                );
                 return CodexStatus::InitiateShutdown;
             }
             EventMsg::TokenCount(TokenUsage { total_tokens, .. }) => {
@@ -204,14 +204,6 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                 #[allow(clippy::expect_used)]
                 std::io::stdout().flush().expect("could not flush stdout");
             }
-            EventMsg::AgentReasoningContent(AgentReasoningContentEvent { text }) => {
-                if !self.show_agent_reasoning {
-                    return CodexStatus::Running;
-                }
-                print!("{text}");
-                #[allow(clippy::expect_used)]
-                std::io::stdout().flush().expect("could not flush stdout");
-            }
             EventMsg::AgentMessage(AgentMessageEvent { message }) => {
                 // if answer_started is false, this means we haven't received any
                 // delta. Thus, we need to print the message as a new answer.
@@ -236,6 +228,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                     call_id.clone(),
                     ExecCommandBegin {
                         command: command.clone(),
+                        start_time: Instant::now(),
                     },
                 );
                 ts_println!(
@@ -251,14 +244,16 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                 call_id,
                 stdout,
                 stderr,
-                duration,
                 exit_code,
             }) => {
                 let exec_command = self.call_id_to_command.remove(&call_id);
-                let (duration, call) = if let Some(ExecCommandBegin { command, .. }) = exec_command
+                let (duration, call) = if let Some(ExecCommandBegin {
+                    command,
+                    start_time,
+                }) = exec_command
                 {
                     (
-                        format!(" in {}", format_duration(duration)),
+                        format!(" in {}", format_elapsed(start_time)),
                         format!("{}", escape_command(&command).style(self.bold)),
                     )
                 } else {
@@ -408,7 +403,6 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                 stdout,
                 stderr,
                 success,
-                ..
             }) => {
                 let patch_begin = self.call_id_to_patch.remove(&call_id);
 
@@ -438,10 +432,6 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                     println!("{}", line.style(self.dimmed));
                 }
             }
-            EventMsg::TurnDiff(TurnDiffEvent { unified_diff }) => {
-                ts_println!(self, "{}", "turn diff:".style(self.magenta));
-                println!("{unified_diff}");
-            }
             EventMsg::ExecApprovalRequest(_) => {
                 // Should we exit?
             }

codex-rs/exec/src/event_processor_with_json_output.rs

@@ -46,9 +46,10 @@ impl EventProcessor for EventProcessorWithJsonOutput {
                 CodexStatus::Running
             }
             EventMsg::TaskComplete(TaskCompleteEvent { last_agent_message }) => {
-                if let Some(output_file) = self.last_message_path.as_deref() {
-                    handle_last_message(last_agent_message.as_deref(), output_file);
-                }
+                handle_last_message(
+                    last_agent_message.as_deref(),
+                    self.last_message_path.as_deref(),
+                );
                 CodexStatus::InitiateShutdown
             }
             EventMsg::ShutdownComplete => CodexStatus::Shutdown,

codex-rs/execpolicy/Cargo.toml

@@ -26,7 +26,7 @@ multimap = "0.10.0"
 path-absolutize = "3.1.1"
 regex-lite = "0.1"
 serde = { version = "1.0.194", features = ["derive"] }
-serde_json = "1.0.142"
+serde_json = "1.0.110"
 serde_with = { version = "3", features = ["macros"] }
 
 [dev-dependencies]

codex-rs/file-search/Cargo.toml

@@ -17,5 +17,5 @@ clap = { version = "4", features = ["derive"] }
 ignore = "0.4.23"
 nucleo-matcher = "0.3.1"
 serde = { version = "1", features = ["derive"] }
-serde_json = "1.0.142"
+serde_json = "1.0.110"
 tokio = { version = "1", features = ["full"] }

codex-rs/mcp-server/src/codex_tool_runner.rs

@@ -252,8 +252,7 @@ async fn run_codex_tool_session_inner(
                     EventMsg::AgentMessage(AgentMessageEvent { .. }) => {
                         // TODO: think how we want to support this in the MCP
                     }
-                    EventMsg::AgentReasoningContent(_)
-                    | EventMsg::TaskStarted
+                    EventMsg::TaskStarted
                     | EventMsg::TokenCount(_)
                     | EventMsg::AgentReasoning(_)
                     | EventMsg::McpToolCallBegin(_)
@@ -264,7 +263,6 @@ async fn run_codex_tool_session_inner(
                     | EventMsg::BackgroundEvent(_)
                     | EventMsg::PatchApplyBegin(_)
                     | EventMsg::PatchApplyEnd(_)
-                    | EventMsg::TurnDiff(_)
                     | EventMsg::GetHistoryEntryResponse(_)
                     | EventMsg::PlanUpdate(_)
                     | EventMsg::ShutdownComplete => {

codex-rs/mcp-server/src/conversation_loop.rs

@@ -90,15 +90,13 @@ pub async fn run_conversation_loop(
                     EventMsg::AgentMessage(AgentMessageEvent { .. }) => {
                         // TODO: think how we want to support this in the MCP
                     }
-                    EventMsg::AgentReasoningContent(_)
-                    | EventMsg::TaskStarted
+                    EventMsg::TaskStarted
                     | EventMsg::TokenCount(_)
                     | EventMsg::AgentReasoning(_)
                     | EventMsg::McpToolCallBegin(_)
                     | EventMsg::McpToolCallEnd(_)
                     | EventMsg::ExecCommandBegin(_)
                     | EventMsg::ExecCommandEnd(_)
-                    | EventMsg::TurnDiff(_)
                     | EventMsg::BackgroundEvent(_)
                     | EventMsg::ExecCommandOutputDelta(_)
                     | EventMsg::PatchApplyBegin(_)

codex-rs/mcp-server/src/exec_approval.rs

@@ -18,7 +18,7 @@ use crate::codex_tool_runner::INVALID_PARAMS_ERROR_CODE;
 
 /// Conforms to [`mcp_types::ElicitRequestParams`] so that it can be used as the
 /// `params` field of an [`ElicitRequest`].
-#[derive(Debug, Deserialize, Serialize)]
+#[derive(Debug, Serialize)]
 pub struct ExecApprovalElicitRequestParams {
     // These fields are required so that `params`
     // conforms to ElicitRequestParams.

codex-rs/mcp-server/tests/codex_tool.rs

@@ -89,18 +89,14 @@ async fn shell_command_approval_triggers_elicitation() -> anyhow::Result<()> {
     // This is the first request from the server, so the id should be 0 given
     // how things are currently implemented.
     let elicitation_request_id = RequestId::Integer(0);
-    let params = serde_json::from_value::<ExecApprovalElicitRequestParams>(
-        elicitation_request
-            .params
-            .clone()
-            .ok_or_else(|| anyhow::anyhow!("elicitation_request.params must be set"))?,
-    )?;
     let expected_elicitation_request = create_expected_elicitation_request(
         elicitation_request_id.clone(),
         shell_command.clone(),
         workdir_for_shell_function_call.path(),
         codex_request_id.to_string(),
-        params.codex_event_id.clone(),
+        // Internal Codex id: empirically it is 1, but this is
+        // admittedly an internal detail that could change.
+        "1".to_string(),
     )?;
     assert_eq!(expected_elicitation_request, elicitation_request);
 

codex-rs/tui/Cargo.toml

@@ -48,8 +48,6 @@ serde_json = { version = "1", features = ["preserve_order"] }
 shlex = "1.3.0"
 strum = "0.27.2"
 strum_macros = "0.27.2"
-supports-color = "3.0.2"
-textwrap = "0.16.2"
 tokio = { version = "1", features = [
     "io-std",
     "macros",
@@ -62,6 +60,7 @@ tracing-appender = "0.2.3"
 tracing-subscriber = { version = "0.3.19", features = ["env-filter"] }
 tui-input = "0.14.0"
 tui-markdown = "0.3.3"
+tui-textarea = "0.7.0"
 unicode-segmentation = "1.12.0"
 unicode-width = "0.1"
 uuid = "1"
@@ -71,5 +70,3 @@ uuid = "1"
 [dev-dependencies]
 insta = "1.43.1"
 pretty_assertions = "1"
-rand = "0.8"
-chrono = { version = "0.4", features = ["serde"] }

codex-rs/tui/src/app.rs

@@ -438,15 +438,14 @@ impl App<'_> {
             );
             self.pending_history_lines.clear();
         }
-        terminal.draw(|frame| match &mut self.app_state {
+        match &mut self.app_state {
             AppState::Chat { widget } => {
-                if let Some((x, y)) = widget.cursor_pos(frame.area()) {
-                    frame.set_cursor_position((x, y));
-                }
-                frame.render_widget_ref(&**widget, frame.area())
+                terminal.draw(|frame| frame.render_widget_ref(&**widget, frame.area()))?;
             }
-            AppState::GitWarning { screen } => frame.render_widget_ref(&*screen, frame.area()),
-        })?;
+            AppState::GitWarning { screen } => {
+                terminal.draw(|frame| frame.render_widget_ref(&*screen, frame.area()))?;
+            }
+        }
         Ok(())
     }
 

codex-rs/tui/src/bottom_pane/chat_composer.rs

@@ -1,11 +1,6 @@
 use codex_core::protocol::TokenUsage;
-use crossterm::event::KeyCode;
 use crossterm::event::KeyEvent;
-use crossterm::event::KeyModifiers;
 use ratatui::buffer::Buffer;
-use ratatui::layout::Constraint;
-use ratatui::layout::Layout;
-use ratatui::layout::Margin;
 use ratatui::layout::Rect;
 use ratatui::style::Color;
 use ratatui::style::Style;
@@ -13,11 +8,13 @@ use ratatui::style::Styled;
 use ratatui::style::Stylize;
 use ratatui::text::Line;
 use ratatui::text::Span;
-use ratatui::widgets::Block;
 use ratatui::widgets::BorderType;
 use ratatui::widgets::Borders;
-use ratatui::widgets::StatefulWidgetRef;
+use ratatui::widgets::Widget;
 use ratatui::widgets::WidgetRef;
+use tui_textarea::Input;
+use tui_textarea::Key;
+use tui_textarea::TextArea;
 
 use super::chat_composer_history::ChatComposerHistory;
 use super::command_popup::CommandPopup;
@@ -25,10 +22,7 @@ use super::file_search_popup::FileSearchPopup;
 
 use crate::app_event::AppEvent;
 use crate::app_event_sender::AppEventSender;
-use crate::bottom_pane::textarea::TextArea;
-use crate::bottom_pane::textarea::TextAreaState;
 use codex_file_search::FileMatch;
-use std::cell::RefCell;
 
 const BASE_PLACEHOLDER_TEXT: &str = "...";
 /// If the pasted content exceeds this number of characters, replace it with a
@@ -41,14 +35,8 @@ pub enum InputResult {
     None,
 }
 
-struct TokenUsageInfo {
-    token_usage: TokenUsage,
-    model_context_window: Option<u64>,
-}
-
-pub(crate) struct ChatComposer {
-    textarea: TextArea,
-    textarea_state: RefCell<TextAreaState>,
+pub(crate) struct ChatComposer<'a> {
+    textarea: TextArea<'a>,
     active_popup: ActivePopup,
     app_event_tx: AppEventSender,
     history: ChatComposerHistory,
@@ -57,8 +45,6 @@ pub(crate) struct ChatComposer {
     dismissed_file_popup_token: Option<String>,
     current_file_query: Option<String>,
     pending_pastes: Vec<(String, String)>,
-    token_usage_info: Option<TokenUsageInfo>,
-    has_focus: bool,
 }
 
 /// Popup state – at most one can be visible at any time.
@@ -68,17 +54,20 @@ enum ActivePopup {
     File(FileSearchPopup),
 }
 
-impl ChatComposer {
+impl ChatComposer<'_> {
     pub fn new(
         has_input_focus: bool,
         app_event_tx: AppEventSender,
         enhanced_keys_supported: bool,
     ) -> Self {
+        let mut textarea = TextArea::default();
+        textarea.set_placeholder_text(BASE_PLACEHOLDER_TEXT);
+        textarea.set_cursor_line_style(ratatui::style::Style::default());
+
         let use_shift_enter_hint = enhanced_keys_supported;
 
-        Self {
-            textarea: TextArea::new(),
-            textarea_state: RefCell::new(TextAreaState::default()),
+        let mut this = Self {
+            textarea,
             active_popup: ActivePopup::None,
             app_event_tx,
             history: ChatComposerHistory::new(),
@@ -87,13 +76,13 @@ impl ChatComposer {
             dismissed_file_popup_token: None,
             current_file_query: None,
             pending_pastes: Vec::new(),
-            token_usage_info: None,
-            has_focus: has_input_focus,
-        }
+        };
+        this.update_border(has_input_focus);
+        this
     }
 
-    pub fn desired_height(&self, width: u16) -> u16 {
-        self.textarea.desired_height(width - 1)
+    pub fn desired_height(&self) -> u16 {
+        self.textarea.lines().len().max(1) as u16
             + match &self.active_popup {
                 ActivePopup::None => 1u16,
                 ActivePopup::Command(c) => c.calculate_required_height(),
@@ -101,21 +90,6 @@ impl ChatComposer {
             }
     }
 
-    pub fn cursor_pos(&self, area: Rect) -> Option<(u16, u16)> {
-        let popup_height = match &self.active_popup {
-            ActivePopup::Command(popup) => popup.calculate_required_height(),
-            ActivePopup::File(popup) => popup.calculate_required_height(),
-            ActivePopup::None => 1,
-        };
-        let [textarea_rect, _] =
-            Layout::vertical([Constraint::Min(0), Constraint::Max(popup_height)]).areas(area);
-        let mut textarea_rect = textarea_rect;
-        textarea_rect.width = textarea_rect.width.saturating_sub(1);
-        textarea_rect.x += 1;
-        let state = self.textarea_state.borrow();
-        self.textarea.cursor_pos_with_state(textarea_rect, &state)
-    }
-
     /// Returns true if the composer currently contains no user input.
     pub(crate) fn is_empty(&self) -> bool {
         self.textarea.is_empty()
@@ -129,10 +103,28 @@ impl ChatComposer {
         token_usage: TokenUsage,
         model_context_window: Option<u64>,
     ) {
-        self.token_usage_info = Some(TokenUsageInfo {
-            token_usage,
-            model_context_window,
-        });
+        let placeholder = match (token_usage.total_tokens, model_context_window) {
+            (total_tokens, Some(context_window)) => {
+                let percent_remaining: u8 = if context_window > 0 {
+                    // Calculate the percentage of context left.
+                    let percent = 100.0 - (total_tokens as f32 / context_window as f32 * 100.0);
+                    percent.clamp(0.0, 100.0) as u8
+                } else {
+                    // If we don't have a context window, we cannot compute the
+                    // percentage.
+                    100
+                };
+                // When https://github.com/openai/codex/issues/1257 is resolved,
+                // check if `percent_remaining < 25`, and if so, recommend
+                // /compact.
+                format!("{BASE_PLACEHOLDER_TEXT} — {percent_remaining}% context left")
+            }
+            (total_tokens, None) => {
+                format!("{BASE_PLACEHOLDER_TEXT} — {total_tokens} tokens used")
+            }
+        };
+
+        self.textarea.set_placeholder_text(placeholder);
     }
 
     /// Record the history metadata advertised by `SessionConfiguredEvent` so
@@ -150,12 +142,8 @@ impl ChatComposer {
         offset: usize,
         entry: Option<String>,
     ) -> bool {
-        let Some(text) = self.history.on_entry_response(log_id, offset, entry) else {
-            return false;
-        };
-        self.textarea.set_text(&text);
-        self.textarea.set_cursor(0);
-        true
+        self.history
+            .on_entry_response(log_id, offset, entry, &mut self.textarea)
     }
 
     pub fn handle_paste(&mut self, pasted: String) -> bool {
@@ -191,7 +179,7 @@ impl ChatComposer {
 
     pub fn set_ctrl_c_quit_hint(&mut self, show: bool, has_focus: bool) {
         self.ctrl_c_quit_hint = show;
-        self.set_has_focus(has_focus);
+        self.update_border(has_focus);
     }
 
     /// Handle a key event coming from the main UI.
@@ -219,47 +207,49 @@ impl ChatComposer {
             unreachable!();
         };
 
-        match key_event {
-            KeyEvent {
-                code: KeyCode::Up, ..
-            } => {
+        match key_event.into() {
+            Input { key: Key::Up, .. } => {
                 popup.move_up();
                 (InputResult::None, true)
             }
-            KeyEvent {
-                code: KeyCode::Down,
-                ..
-            } => {
+            Input { key: Key::Down, .. } => {
                 popup.move_down();
                 (InputResult::None, true)
             }
-            KeyEvent {
-                code: KeyCode::Tab, ..
-            } => {
+            Input { key: Key::Tab, .. } => {
                 if let Some(cmd) = popup.selected_command() {
-                    let first_line = self.textarea.text().lines().next().unwrap_or("");
+                    let first_line = self
+                        .textarea
+                        .lines()
+                        .first()
+                        .map(|s| s.as_str())
+                        .unwrap_or("");
 
                     let starts_with_cmd = first_line
                         .trim_start()
                         .starts_with(&format!("/{}", cmd.command()));
 
                     if !starts_with_cmd {
-                        self.textarea.set_text(&format!("/{} ", cmd.command()));
+                        self.textarea.select_all();
+                        self.textarea.cut();
+                        let _ = self.textarea.insert_str(format!("/{} ", cmd.command()));
                     }
                 }
                 (InputResult::None, true)
             }
-            KeyEvent {
-                code: KeyCode::Enter,
-                modifiers: KeyModifiers::NONE,
-                ..
+            Input {
+                key: Key::Enter,
+                shift: false,
+                alt: false,
+                ctrl: false,
             } => {
                 if let Some(cmd) = popup.selected_command() {
                     // Send command to the app layer.
                     self.app_event_tx.send(AppEvent::DispatchCommand(*cmd));
 
                     // Clear textarea so no residual text remains.
-                    self.textarea.set_text("");
+                    self.textarea.select_all();
+                    self.textarea.cut();
 
                     // Hide popup since the command has been dispatched.
                     self.active_popup = ActivePopup::None;
@@ -278,23 +268,16 @@ impl ChatComposer {
             unreachable!();
         };
 
-        match key_event {
-            KeyEvent {
-                code: KeyCode::Up, ..
-            } => {
+        match key_event.into() {
+            Input { key: Key::Up, .. } => {
                 popup.move_up();
                 (InputResult::None, true)
             }
-            KeyEvent {
-                code: KeyCode::Down,
-                ..
-            } => {
+            Input { key: Key::Down, .. } => {
                 popup.move_down();
                 (InputResult::None, true)
             }
-            KeyEvent {
-                code: KeyCode::Esc, ..
-            } => {
+            Input { key: Key::Esc, .. } => {
                 // Hide popup without modifying text, remember token to avoid immediate reopen.
                 if let Some(tok) = Self::current_at_token(&self.textarea) {
                     self.dismissed_file_popup_token = Some(tok.to_string());
@@ -302,13 +285,12 @@ impl ChatComposer {
                 self.active_popup = ActivePopup::None;
                 (InputResult::None, true)
             }
-            KeyEvent {
-                code: KeyCode::Tab, ..
-            }
-            | KeyEvent {
-                code: KeyCode::Enter,
-                modifiers: KeyModifiers::NONE,
-                ..
+            Input { key: Key::Tab, .. }
+            | Input {
+                key: Key::Enter,
+                ctrl: false,
+                alt: false,
+                shift: false,
             } => {
                 if let Some(sel) = popup.selected_match() {
                     let sel_path = sel.to_string();
@@ -333,89 +315,46 @@ impl ChatComposer {
     /// - A token is delimited by ASCII whitespace (space, tab, newline).
     /// - If the token under the cursor starts with `@` and contains at least
     ///   one additional character, that token (without `@`) is returned.
-    fn current_at_token(textarea: &TextArea) -> Option<String> {
-        let cursor_offset = textarea.cursor();
-        let text = textarea.text();
+    fn current_at_token(textarea: &tui_textarea::TextArea) -> Option<String> {
+        let (row, col) = textarea.cursor();
 
-        // Adjust the provided byte offset to the nearest valid char boundary at or before it.
-        let mut safe_cursor = cursor_offset.min(text.len());
-        // If we're not on a char boundary, move back to the start of the current char.
-        if safe_cursor < text.len() && !text.is_char_boundary(safe_cursor) {
-            // Find the last valid boundary <= cursor_offset.
-            safe_cursor = text
-                .char_indices()
-                .map(|(i, _)| i)
-                .take_while(|&i| i <= cursor_offset)
-                .last()
-                .unwrap_or(0);
-        }
+        // Guard against out-of-bounds rows.
+        let line = textarea.lines().get(row)?.as_str();
 
-        // Split the line around the (now safe) cursor position.
-        let before_cursor = &text[..safe_cursor];
-        let after_cursor = &text[safe_cursor..];
+        // Calculate byte offset for cursor position
+        let cursor_byte_offset = line.chars().take(col).map(|c| c.len_utf8()).sum::<usize>();
 
-        // Detect whether we're on whitespace at the cursor boundary.
-        let at_whitespace = if safe_cursor < text.len() {
-            text[safe_cursor..]
-                .chars()
-                .next()
-                .map(|c| c.is_whitespace())
-                .unwrap_or(false)
-        } else {
-            false
-        };
+        // Split the line at the cursor position so we can search for word
+        // boundaries on both sides.
+        let before_cursor = &line[..cursor_byte_offset];
+        let after_cursor = &line[cursor_byte_offset..];
 
-        // Left candidate: token containing the cursor position.
-        let start_left = before_cursor
+        // Find start index (first character **after** the previous multi-byte whitespace).
+        let start_idx = before_cursor
             .char_indices()
             .rfind(|(_, c)| c.is_whitespace())
             .map(|(idx, c)| idx + c.len_utf8())
             .unwrap_or(0);
-        let end_left_rel = after_cursor
+
+        // Find end index (first multi-byte whitespace **after** the cursor position).
+        let end_rel_idx = after_cursor
             .char_indices()
             .find(|(_, c)| c.is_whitespace())
             .map(|(idx, _)| idx)
             .unwrap_or(after_cursor.len());
-        let end_left = safe_cursor + end_left_rel;
-        let token_left = if start_left < end_left {
-            Some(&text[start_left..end_left])
+        let end_idx = cursor_byte_offset + end_rel_idx;
+
+        if start_idx >= end_idx {
+            return None;
+        }
+
+        let token = &line[start_idx..end_idx];
+
+        if token.starts_with('@') && token.len() > 1 {
+            Some(token[1..].to_string())
         } else {
             None
-        };
-
-        // Right candidate: token immediately after any whitespace from the cursor.
-        let ws_len_right: usize = after_cursor
-            .chars()
-            .take_while(|c| c.is_whitespace())
-            .map(|c| c.len_utf8())
-            .sum();
-        let start_right = safe_cursor + ws_len_right;
-        let end_right_rel = text[start_right..]
-            .char_indices()
-            .find(|(_, c)| c.is_whitespace())
-            .map(|(idx, _)| idx)
-            .unwrap_or(text.len() - start_right);
-        let end_right = start_right + end_right_rel;
-        let token_right = if start_right < end_right {
-            Some(&text[start_right..end_right])
-        } else {
-            None
-        };
-
-        let left_at = token_left
-            .filter(|t| t.starts_with('@') && t.len() > 1)
-            .map(|t| t[1..].to_string());
-        let right_at = token_right
-            .filter(|t| t.starts_with('@') && t.len() > 1)
-            .map(|t| t[1..].to_string());
-
-        if at_whitespace {
-            return right_at.or(left_at);
         }
-        if after_cursor.starts_with('@') {
-            return right_at.or(left_at);
-        }
-        left_at.or(right_at)
     }
 
     /// Replace the active `@token` (the one under the cursor) with `path`.
@@ -424,73 +363,94 @@ impl ChatComposer {
     /// where the cursor is within the token and regardless of how many
     /// `@tokens` exist in the line.
     fn insert_selected_path(&mut self, path: &str) {
-        let cursor_offset = self.textarea.cursor();
-        let text = self.textarea.text();
+        let (row, col) = self.textarea.cursor();
 
-        let before_cursor = &text[..cursor_offset];
-        let after_cursor = &text[cursor_offset..];
+        // Materialize the textarea lines so we can mutate them easily.
+        let mut lines: Vec<String> = self.textarea.lines().to_vec();
 
-        // Determine token boundaries.
-        let start_idx = before_cursor
-            .char_indices()
-            .rfind(|(_, c)| c.is_whitespace())
-            .map(|(idx, c)| idx + c.len_utf8())
-            .unwrap_or(0);
+        if let Some(line) = lines.get_mut(row) {
+            // Calculate byte offset for cursor position
+            let cursor_byte_offset = line.chars().take(col).map(|c| c.len_utf8()).sum::<usize>();
 
-        let end_rel_idx = after_cursor
-            .char_indices()
-            .find(|(_, c)| c.is_whitespace())
-            .map(|(idx, _)| idx)
-            .unwrap_or(after_cursor.len());
-        let end_idx = cursor_offset + end_rel_idx;
+            let before_cursor = &line[..cursor_byte_offset];
+            let after_cursor = &line[cursor_byte_offset..];
 
-        // Replace the slice `[start_idx, end_idx)` with the chosen path and a trailing space.
-        let mut new_text =
-            String::with_capacity(text.len() - (end_idx - start_idx) + path.len() + 1);
-        new_text.push_str(&text[..start_idx]);
-        new_text.push_str(path);
-        new_text.push(' ');
-        new_text.push_str(&text[end_idx..]);
+            // Determine token boundaries.
+            let start_idx = before_cursor
+                .char_indices()
+                .rfind(|(_, c)| c.is_whitespace())
+                .map(|(idx, c)| idx + c.len_utf8())
+                .unwrap_or(0);
 
-        self.textarea.set_text(&new_text);
+            let end_rel_idx = after_cursor
+                .char_indices()
+                .find(|(_, c)| c.is_whitespace())
+                .map(|(idx, _)| idx)
+                .unwrap_or(after_cursor.len());
+            let end_idx = cursor_byte_offset + end_rel_idx;
+
+            // Replace the slice `[start_idx, end_idx)` with the chosen path and a trailing space.
+            let mut new_line =
+                String::with_capacity(line.len() - (end_idx - start_idx) + path.len() + 1);
+            new_line.push_str(&line[..start_idx]);
+            new_line.push_str(path);
+            new_line.push(' ');
+            new_line.push_str(&line[end_idx..]);
+
+            *line = new_line;
+
+            // Re-populate the textarea.
+            let new_text = lines.join("\n");
+            self.textarea.select_all();
+            self.textarea.cut();
+            let _ = self.textarea.insert_str(new_text);
+
+            // Note: tui-textarea currently exposes only relative cursor
+            // movements. Leaving the cursor position unchanged is acceptable
+            // as subsequent typing will move the cursor naturally.
+        }
     }
 
     /// Handle key event when no popup is visible.
     fn handle_key_event_without_popup(&mut self, key_event: KeyEvent) -> (InputResult, bool) {
-        match key_event {
+        let input: Input = key_event.into();
+        match input {
             // -------------------------------------------------------------
             // History navigation (Up / Down) – only when the composer is not
             // empty or when the cursor is at the correct position, to avoid
             // interfering with normal cursor movement.
             // -------------------------------------------------------------
-            KeyEvent {
-                code: KeyCode::Up | KeyCode::Down,
-                ..
-            } => {
-                if self
-                    .history
-                    .should_handle_navigation(self.textarea.text(), self.textarea.cursor())
-                {
-                    let replace_text = match key_event.code {
-                        KeyCode::Up => self.history.navigate_up(&self.app_event_tx),
-                        KeyCode::Down => self.history.navigate_down(&self.app_event_tx),
-                        _ => unreachable!(),
-                    };
-                    if let Some(text) = replace_text {
-                        self.textarea.set_text(&text);
-                        self.textarea.set_cursor(0);
+            Input { key: Key::Up, .. } => {
+                if self.history.should_handle_navigation(&self.textarea) {
+                    let consumed = self
+                        .history
+                        .navigate_up(&mut self.textarea, &self.app_event_tx);
+                    if consumed {
                         return (InputResult::None, true);
                     }
                 }
-                self.handle_input_basic(key_event)
+                self.handle_input_basic(input)
             }
-            KeyEvent {
-                code: KeyCode::Enter,
-                modifiers: KeyModifiers::NONE,
-                ..
+            Input { key: Key::Down, .. } => {
+                if self.history.should_handle_navigation(&self.textarea) {
+                    let consumed = self
+                        .history
+                        .navigate_down(&mut self.textarea, &self.app_event_tx);
+                    if consumed {
+                        return (InputResult::None, true);
+                    }
+                }
+                self.handle_input_basic(input)
+            }
+            Input {
+                key: Key::Enter,
+                shift: false,
+                alt: false,
+                ctrl: false,
             } => {
-                let mut text = self.textarea.text().to_string();
-                self.textarea.set_text("");
+                let mut text = self.textarea.lines().join("\n");
+                self.textarea.select_all();
+                self.textarea.cut();
 
                 // Replace all pending pastes in the text
                 for (placeholder, actual) in &self.pending_pastes {
@@ -507,15 +467,41 @@ impl ChatComposer {
                     (InputResult::Submitted(text), true)
                 }
             }
+            Input {
+                key: Key::Enter, ..
+            }
+            | Input {
+                key: Key::Char('j'),
+                ctrl: true,
+                alt: false,
+                shift: false,
+            } => {
+                self.textarea.insert_newline();
+                (InputResult::None, true)
+            }
+            Input {
+                key: Key::Char('d'),
+                ctrl: true,
+                alt: false,
+                shift: false,
+            } => {
+                self.textarea.input(Input {
+                    key: Key::Delete,
+                    ctrl: false,
+                    alt: false,
+                    shift: false,
+                });
+                (InputResult::None, true)
+            }
             input => self.handle_input_basic(input),
         }
     }
 
     /// Handle generic Input events that modify the textarea content.
-    fn handle_input_basic(&mut self, input: KeyEvent) -> (InputResult, bool) {
+    fn handle_input_basic(&mut self, input: Input) -> (InputResult, bool) {
         // Special handling for backspace on placeholders
-        if let KeyEvent {
-            code: KeyCode::Backspace,
+        if let Input {
+            key: Key::Backspace,
             ..
         } = input
         {
@@ -524,9 +510,20 @@ impl ChatComposer {
             }
         }
 
+        if let Input {
+            key: Key::Char('u'),
+            ctrl: true,
+            alt: false,
+            ..
+        } = input
+        {
+            self.textarea.delete_line_by_head();
+            return (InputResult::None, true);
+        }
+
         // Normal input handling
         self.textarea.input(input);
-        let text_after = self.textarea.text();
+        let text_after = self.textarea.lines().join("\n");
 
         // Check if any placeholders were removed and remove their corresponding pending pastes
         self.pending_pastes
@@ -538,16 +535,21 @@ impl ChatComposer {
     /// Attempts to remove a placeholder if the cursor is at the end of one.
     /// Returns true if a placeholder was removed.
     fn try_remove_placeholder_at_cursor(&mut self) -> bool {
-        let p = self.textarea.cursor();
-        let text = self.textarea.text();
+        let (row, col) = self.textarea.cursor();
+        let line = self
+            .textarea
+            .lines()
+            .get(row)
+            .map(|s| s.as_str())
+            .unwrap_or("");
 
         // Find any placeholder that ends at the cursor position
         let placeholder_to_remove = self.pending_pastes.iter().find_map(|(ph, _)| {
-            if p < ph.len() {
+            if col < ph.len() {
                 return None;
             }
-            let potential_ph_start = p - ph.len();
-            if text[potential_ph_start..p] == *ph {
+            let potential_ph_start = col - ph.len();
+            if line[potential_ph_start..col] == *ph {
                 Some(ph.clone())
             } else {
                 None
@@ -555,7 +557,17 @@ impl ChatComposer {
         });
 
         if let Some(placeholder) = placeholder_to_remove {
-            self.textarea.replace_range(p - placeholder.len()..p, "");
+            // Remove the entire placeholder from the text
+            let placeholder_len = placeholder.len();
+            for _ in 0..placeholder_len {
+                self.textarea.input(Input {
+                    key: Key::Backspace,
+                    ctrl: false,
+                    alt: false,
+                    shift: false,
+                });
+            }
+            // Remove from pending pastes
             self.pending_pastes.retain(|(ph, _)| ph != &placeholder);
             true
         } else {
@@ -567,7 +579,16 @@ impl ChatComposer {
     /// textarea. This must be called after every modification that can change
     /// the text so the popup is shown/updated/hidden as appropriate.
     fn sync_command_popup(&mut self) {
-        let first_line = self.textarea.text().lines().next().unwrap_or("");
+        // Inspect only the first line to decide whether to show the popup. In
+        // the common case (no leading slash) we avoid copying the entire
+        // textarea contents.
+        let first_line = self
+            .textarea
+            .lines()
+            .first()
+            .map(|s| s.as_str())
+            .unwrap_or("");
+
         let input_starts_with_slash = first_line.starts_with('/');
         match &mut self.active_popup {
             ActivePopup::Command(popup) => {
@@ -623,29 +644,74 @@ impl ChatComposer {
         self.dismissed_file_popup_token = None;
     }
 
-    fn set_has_focus(&mut self, has_focus: bool) {
-        self.has_focus = has_focus;
+    fn update_border(&mut self, has_focus: bool) {
+        let border_style = if has_focus {
+            Style::default().fg(Color::Cyan)
+        } else {
+            Style::default().dim()
+        };
+
+        self.textarea.set_block(
+            ratatui::widgets::Block::default()
+                .borders(Borders::LEFT)
+                .border_type(BorderType::QuadrantOutside)
+                .border_style(border_style),
+        );
     }
 }
 
-impl WidgetRef for &ChatComposer {
+impl WidgetRef for &ChatComposer<'_> {
     fn render_ref(&self, area: Rect, buf: &mut Buffer) {
-        let popup_height = match &self.active_popup {
-            ActivePopup::Command(popup) => popup.calculate_required_height(),
-            ActivePopup::File(popup) => popup.calculate_required_height(),
-            ActivePopup::None => 1,
-        };
-        let [textarea_rect, popup_rect] =
-            Layout::vertical([Constraint::Min(0), Constraint::Max(popup_height)]).areas(area);
         match &self.active_popup {
             ActivePopup::Command(popup) => {
-                popup.render_ref(popup_rect, buf);
+                let popup_height = popup.calculate_required_height();
+
+                // Split the provided rect so that the popup is rendered at the
+                // **bottom** and the textarea occupies the remaining space above.
+                let popup_height = popup_height.min(area.height);
+                let textarea_rect = Rect {
+                    x: area.x,
+                    y: area.y,
+                    width: area.width,
+                    height: area.height.saturating_sub(popup_height),
+                };
+                let popup_rect = Rect {
+                    x: area.x,
+                    y: area.y + textarea_rect.height,
+                    width: area.width,
+                    height: popup_height,
+                };
+
+                popup.render(popup_rect, buf);
+                self.textarea.render(textarea_rect, buf);
             }
             ActivePopup::File(popup) => {
-                popup.render_ref(popup_rect, buf);
+                let popup_height = popup.calculate_required_height();
+
+                let popup_height = popup_height.min(area.height);
+                let textarea_rect = Rect {
+                    x: area.x,
+                    y: area.y,
+                    width: area.width,
+                    height: area.height.saturating_sub(popup_height),
+                };
+                let popup_rect = Rect {
+                    x: area.x,
+                    y: area.y + textarea_rect.height,
+                    width: area.width,
+                    height: popup_height,
+                };
+
+                popup.render(popup_rect, buf);
+                self.textarea.render(textarea_rect, buf);
             }
             ActivePopup::None => {
-                let bottom_line_rect = popup_rect;
+                let mut textarea_rect = area;
+                textarea_rect.height = textarea_rect.height.saturating_sub(1);
+                self.textarea.render(textarea_rect, buf);
+                let mut bottom_line_rect = area;
+                bottom_line_rect.y += textarea_rect.height;
+                bottom_line_rect.height = 1;
                 let key_hint_style = Style::default().fg(Color::Cyan);
                 let hint = if self.ctrl_c_quit_hint {
                     vec![
@@ -674,56 +740,6 @@ impl WidgetRef for &ChatComposer {
                     .render_ref(bottom_line_rect, buf);
             }
         }
-        Block::default()
-            .border_style(Style::default().dim())
-            .borders(Borders::LEFT)
-            .border_type(BorderType::QuadrantOutside)
-            .border_style(Style::default().fg(if self.has_focus {
-                Color::Cyan
-            } else {
-                Color::Gray
-            }))
-            .render_ref(
-                Rect::new(textarea_rect.x, textarea_rect.y, 1, textarea_rect.height),
-                buf,
-            );
-        let mut textarea_rect = textarea_rect;
-        textarea_rect.width = textarea_rect.width.saturating_sub(1);
-        textarea_rect.x += 1;
-        let mut state = self.textarea_state.borrow_mut();
-        StatefulWidgetRef::render_ref(&(&self.textarea), textarea_rect, buf, &mut state);
-        if self.textarea.text().is_empty() {
-            let placeholder = if let Some(token_usage_info) = &self.token_usage_info {
-                let token_usage = &token_usage_info.token_usage;
-                let model_context_window = token_usage_info.model_context_window;
-                match (token_usage.total_tokens, model_context_window) {
-                    (total_tokens, Some(context_window)) => {
-                        let percent_remaining: u8 = if context_window > 0 {
-                            // Calculate the percentage of context left.
-                            let percent =
-                                100.0 - (total_tokens as f32 / context_window as f32 * 100.0);
-                            percent.clamp(0.0, 100.0) as u8
-                        } else {
-                            // If we don't have a context window, we cannot compute the
-                            // percentage.
-                            100
-                        };
-                        // When https://github.com/openai/codex/issues/1257 is resolved,
-                        // check if `percent_remaining < 25`, and if so, recommend
-                        // /compact.
-                        format!("{BASE_PLACEHOLDER_TEXT} — {percent_remaining}% context left")
-                    }
-                    (total_tokens, None) => {
-                        format!("{BASE_PLACEHOLDER_TEXT} — {total_tokens} tokens used")
-                    }
-                }
-            } else {
-                BASE_PLACEHOLDER_TEXT.to_string()
-            };
-            Line::from(placeholder)
-                .style(Style::default().dim())
-                .render_ref(textarea_rect.inner(Margin::new(1, 0)), buf);
-        }
     }
 }
 
@@ -733,7 +749,7 @@ mod tests {
     use crate::bottom_pane::ChatComposer;
     use crate::bottom_pane::InputResult;
     use crate::bottom_pane::chat_composer::LARGE_PASTE_CHAR_THRESHOLD;
-    use crate::bottom_pane::textarea::TextArea;
+    use tui_textarea::TextArea;
 
     #[test]
     fn test_current_at_token_basic_cases() {
@@ -776,9 +792,9 @@ mod tests {
         ];
 
         for (input, cursor_pos, expected, description) in test_cases {
-            let mut textarea = TextArea::new();
+            let mut textarea = TextArea::default();
             textarea.insert_str(input);
-            textarea.set_cursor(cursor_pos);
+            textarea.move_cursor(tui_textarea::CursorMove::Jump(0, cursor_pos));
 
             let result = ChatComposer::current_at_token(&textarea);
             assert_eq!(
@@ -810,9 +826,9 @@ mod tests {
         ];
 
         for (input, cursor_pos, expected, description) in test_cases {
-            let mut textarea = TextArea::new();
+            let mut textarea = TextArea::default();
             textarea.insert_str(input);
-            textarea.set_cursor(cursor_pos);
+            textarea.move_cursor(tui_textarea::CursorMove::Jump(0, cursor_pos));
 
             let result = ChatComposer::current_at_token(&textarea);
             assert_eq!(
@@ -847,13 +863,13 @@ mod tests {
             // Full-width space boundaries
             (
                 "test　@İstanbul",
-                8,
+                6,
                 Some("İstanbul".to_string()),
                 "@ token after full-width space",
             ),
             (
                 "@ЙЦУ　@诶",
-                10,
+                6,
                 Some("诶".to_string()),
                 "Full-width space between Unicode tokens",
             ),
@@ -867,9 +883,9 @@ mod tests {
         ];
 
         for (input, cursor_pos, expected, description) in test_cases {
-            let mut textarea = TextArea::new();
+            let mut textarea = TextArea::default();
             textarea.insert_str(input);
-            textarea.set_cursor(cursor_pos);
+            textarea.move_cursor(tui_textarea::CursorMove::Jump(0, cursor_pos));
 
             let result = ChatComposer::current_at_token(&textarea);
             assert_eq!(
@@ -891,7 +907,7 @@ mod tests {
 
         let needs_redraw = composer.handle_paste("hello".to_string());
         assert!(needs_redraw);
-        assert_eq!(composer.textarea.text(), "hello");
+        assert_eq!(composer.textarea.lines(), ["hello"]);
         assert!(composer.pending_pastes.is_empty());
 
         let (result, _) =
@@ -916,7 +932,7 @@ mod tests {
         let needs_redraw = composer.handle_paste(large.clone());
         assert!(needs_redraw);
         let placeholder = format!("[Pasted Content {} chars]", large.chars().count());
-        assert_eq!(composer.textarea.text(), placeholder);
+        assert_eq!(composer.textarea.lines(), [placeholder.as_str()]);
         assert_eq!(composer.pending_pastes.len(), 1);
         assert_eq!(composer.pending_pastes[0].0, placeholder);
         assert_eq!(composer.pending_pastes[0].1, large);
@@ -992,7 +1008,7 @@ mod tests {
                 composer.handle_paste("b".repeat(LARGE_PASTE_CHAR_THRESHOLD + 4));
                 composer.handle_paste("c".repeat(LARGE_PASTE_CHAR_THRESHOLD + 6));
                 // Move cursor to end and press backspace
-                composer.textarea.set_cursor(composer.textarea.text().len());
+                composer.textarea.move_cursor(tui_textarea::CursorMove::End);
                 composer.handle_key_event(KeyEvent::new(KeyCode::Backspace, KeyModifiers::NONE));
             }
 
@@ -1107,7 +1123,7 @@ mod tests {
                     current_pos += content.len();
                 }
                 (
-                    composer.textarea.text().to_string(),
+                    composer.textarea.lines().join("\n"),
                     composer.pending_pastes.len(),
                     current_pos,
                 )
@@ -1118,18 +1134,25 @@ mod tests {
         let mut deletion_states = vec![];
 
         // First deletion
-        composer.textarea.set_cursor(states[0].2);
+        composer
+            .textarea
+            .move_cursor(tui_textarea::CursorMove::Jump(0, states[0].2 as u16));
         composer.handle_key_event(KeyEvent::new(KeyCode::Backspace, KeyModifiers::NONE));
         deletion_states.push((
-            composer.textarea.text().to_string(),
+            composer.textarea.lines().join("\n"),
             composer.pending_pastes.len(),
         ));
 
         // Second deletion
-        composer.textarea.set_cursor(composer.textarea.text().len());
+        composer
+            .textarea
+            .move_cursor(tui_textarea::CursorMove::Jump(
+                0,
+                composer.textarea.lines().join("\n").len() as u16,
+            ));
         composer.handle_key_event(KeyEvent::new(KeyCode::Backspace, KeyModifiers::NONE));
         deletion_states.push((
-            composer.textarea.text().to_string(),
+            composer.textarea.lines().join("\n"),
             composer.pending_pastes.len(),
         ));
 
@@ -1168,13 +1191,17 @@ mod tests {
                 composer.handle_paste(paste.clone());
                 composer
                     .textarea
-                    .set_cursor((placeholder.len() - pos_from_end) as usize);
+                    .move_cursor(tui_textarea::CursorMove::Jump(
+                        0,
+                        (placeholder.len() - pos_from_end) as u16,
+                    ));
                 composer.handle_key_event(KeyEvent::new(KeyCode::Backspace, KeyModifiers::NONE));
                 let result = (
-                    composer.textarea.text().contains(&placeholder),
+                    composer.textarea.lines().join("\n").contains(&placeholder),
                     composer.pending_pastes.len(),
                 );
-                composer.textarea.set_text("");
+                composer.textarea.select_all();
+                composer.textarea.cut();
                 result
             })
             .collect();

codex-rs/tui/src/bottom_pane/chat_composer_history.rs

@@ -1,5 +1,8 @@
 use std::collections::HashMap;
 
+use tui_textarea::CursorMove;
+use tui_textarea::TextArea;
+
 use crate::app_event::AppEvent;
 use crate::app_event_sender::AppEventSender;
 use codex_core::protocol::Op;
@@ -64,52 +67,59 @@ impl ChatComposerHistory {
 
     /// Should Up/Down key presses be interpreted as history navigation given
     /// the current content and cursor position of `textarea`?
-    pub fn should_handle_navigation(&self, text: &str, cursor: usize) -> bool {
+    pub fn should_handle_navigation(&self, textarea: &TextArea) -> bool {
         if self.history_entry_count == 0 && self.local_history.is_empty() {
             return false;
         }
 
-        if text.is_empty() {
+        if textarea.is_empty() {
             return true;
         }
 
         // Textarea is not empty – only navigate when cursor is at start and
         // text matches last recalled history entry so regular editing is not
         // hijacked.
-        if cursor != 0 {
+        let (row, col) = textarea.cursor();
+        if row != 0 || col != 0 {
             return false;
         }
 
-        matches!(&self.last_history_text, Some(prev) if prev == text)
+        let lines = textarea.lines();
+        matches!(&self.last_history_text, Some(prev) if prev == &lines.join("\n"))
     }
 
     /// Handle <Up>. Returns true when the key was consumed and the caller
     /// should request a redraw.
-    pub fn navigate_up(&mut self, app_event_tx: &AppEventSender) -> Option<String> {
+    pub fn navigate_up(&mut self, textarea: &mut TextArea, app_event_tx: &AppEventSender) -> bool {
         let total_entries = self.history_entry_count + self.local_history.len();
         if total_entries == 0 {
-            return None;
+            return false;
         }
 
         let next_idx = match self.history_cursor {
             None => (total_entries as isize) - 1,
-            Some(0) => return None, // already at oldest
+            Some(0) => return true, // already at oldest
             Some(idx) => idx - 1,
         };
 
         self.history_cursor = Some(next_idx);
-        self.populate_history_at_index(next_idx as usize, app_event_tx)
+        self.populate_history_at_index(next_idx as usize, textarea, app_event_tx);
+        true
     }
 
     /// Handle <Down>.
-    pub fn navigate_down(&mut self, app_event_tx: &AppEventSender) -> Option<String> {
+    pub fn navigate_down(
+        &mut self,
+        textarea: &mut TextArea,
+        app_event_tx: &AppEventSender,
+    ) -> bool {
         let total_entries = self.history_entry_count + self.local_history.len();
         if total_entries == 0 {
-            return None;
+            return false;
         }
 
         let next_idx_opt = match self.history_cursor {
-            None => return None, // not browsing
+            None => return false, // not browsing
             Some(idx) if (idx as usize) + 1 >= total_entries => None,
             Some(idx) => Some(idx + 1),
         };
@@ -117,15 +127,16 @@ impl ChatComposerHistory {
         match next_idx_opt {
             Some(idx) => {
                 self.history_cursor = Some(idx);
-                self.populate_history_at_index(idx as usize, app_event_tx)
+                self.populate_history_at_index(idx as usize, textarea, app_event_tx);
             }
             None => {
                 // Past newest – clear and exit browsing mode.
                 self.history_cursor = None;
                 self.last_history_text = None;
-                Some(String::new())
+                self.replace_textarea_content(textarea, "");
             }
         }
+        true
     }
 
     /// Integrate a GetHistoryEntryResponse event.
@@ -134,18 +145,19 @@ impl ChatComposerHistory {
         log_id: u64,
         offset: usize,
         entry: Option<String>,
-    ) -> Option<String> {
+        textarea: &mut TextArea,
+    ) -> bool {
         if self.history_log_id != Some(log_id) {
-            return None;
+            return false;
         }
-        let text = entry?;
+        let Some(text) = entry else { return false };
         self.fetched_history.insert(offset, text.clone());
 
         if self.history_cursor == Some(offset as isize) {
-            self.last_history_text = Some(text.clone());
-            return Some(text);
+            self.replace_textarea_content(textarea, &text);
+            return true;
         }
-        None
+        false
     }
 
     // ---------------------------------------------------------------------
@@ -155,20 +167,21 @@ impl ChatComposerHistory {
     fn populate_history_at_index(
         &mut self,
         global_idx: usize,
+        textarea: &mut TextArea,
         app_event_tx: &AppEventSender,
-    ) -> Option<String> {
+    ) {
         if global_idx >= self.history_entry_count {
             // Local entry.
             if let Some(text) = self
                 .local_history
                 .get(global_idx - self.history_entry_count)
             {
-                self.last_history_text = Some(text.clone());
-                return Some(text.clone());
+                let t = text.clone();
+                self.replace_textarea_content(textarea, &t);
             }
         } else if let Some(text) = self.fetched_history.get(&global_idx) {
-            self.last_history_text = Some(text.clone());
-            return Some(text.clone());
+            let t = text.clone();
+            self.replace_textarea_content(textarea, &t);
         } else if let Some(log_id) = self.history_log_id {
             let op = Op::GetHistoryEntryRequest {
                 offset: global_idx,
@@ -176,7 +189,14 @@ impl ChatComposerHistory {
             };
             app_event_tx.send(AppEvent::CodexOp(op));
         }
-        None
+    }
+
+    fn replace_textarea_content(&mut self, textarea: &mut TextArea, text: &str) {
+        textarea.select_all();
+        textarea.cut();
+        let _ = textarea.insert_str(text);
+        textarea.move_cursor(CursorMove::Jump(0, 0));
+        self.last_history_text = Some(text.to_string());
     }
 }
 
@@ -197,9 +217,11 @@ mod tests {
         // Pretend there are 3 persistent entries.
         history.set_metadata(1, 3);
 
+        let mut textarea = TextArea::default();
+
         // First Up should request offset 2 (latest) and await async data.
-        assert!(history.should_handle_navigation("", 0));
-        assert!(history.navigate_up(&tx).is_none()); // don't replace the text yet
+        assert!(history.should_handle_navigation(&textarea));
+        assert!(history.navigate_up(&mut textarea, &tx));
 
         // Verify that an AppEvent::CodexOp with the correct GetHistoryEntryRequest was sent.
         let event = rx.try_recv().expect("expected AppEvent to be sent");
@@ -213,15 +235,14 @@ mod tests {
             },
             history_request1
         );
+        assert_eq!(textarea.lines().join("\n"), ""); // still empty
 
         // Inject the async response.
-        assert_eq!(
-            Some("latest".into()),
-            history.on_entry_response(1, 2, Some("latest".into()))
-        );
+        assert!(history.on_entry_response(1, 2, Some("latest".into()), &mut textarea));
+        assert_eq!(textarea.lines().join("\n"), "latest");
 
         // Next Up should move to offset 1.
-        assert!(history.navigate_up(&tx).is_none()); // don't replace the text yet
+        assert!(history.navigate_up(&mut textarea, &tx));
 
         // Verify second CodexOp event for offset 1.
         let event2 = rx.try_recv().expect("expected second event");
@@ -236,9 +257,7 @@ mod tests {
             history_request_2
         );
 
-        assert_eq!(
-            Some("older".into()),
-            history.on_entry_response(1, 1, Some("older".into()))
-        );
+        history.on_entry_response(1, 1, Some("older".into()), &mut textarea);
+        assert_eq!(textarea.lines().join("\n"), "older");
     }
 }

codex-rs/tui/src/bottom_pane/mod.rs

@@ -19,7 +19,6 @@ mod chat_composer_history;
 mod command_popup;
 mod file_search_popup;
 mod status_indicator_view;
-mod textarea;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub(crate) enum CancellationEvent {
@@ -37,7 +36,7 @@ use status_indicator_view::StatusIndicatorView;
 pub(crate) struct BottomPane<'a> {
     /// Composer is retained even when a BottomPaneView is displayed so the
     /// input state is retained when the view is closed.
-    composer: ChatComposer,
+    composer: ChatComposer<'a>,
 
     /// If present, this is displayed instead of the `composer`.
     active_view: Option<Box<dyn BottomPaneView<'a> + 'a>>,
@@ -75,19 +74,7 @@ impl BottomPane<'_> {
         self.active_view
             .as_ref()
             .map(|v| v.desired_height(width))
-            .unwrap_or(self.composer.desired_height(width))
-    }
-
-    pub fn cursor_pos(&self, area: Rect) -> Option<(u16, u16)> {
-        // Hide the cursor whenever an overlay view is active (e.g. the
-        // status indicator shown while a task is running, or approval modal).
-        // In these states the textarea is not interactable, so we should not
-        // show its caret.
-        if self.active_view.is_some() {
-            None
-        } else {
-            self.composer.cursor_pos(area)
-        }
+            .unwrap_or(self.composer.desired_height())
     }
 
     /// Forward a key event to the active view or the composer.

codex-rs/tui/src/chatwidget.rs

@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 use std::path::PathBuf;
 use std::sync::Arc;
+use std::time::Duration;
 
 use codex_core::codex_wrapper::CodexConversation;
 use codex_core::codex_wrapper::init_codex;
@@ -389,7 +390,6 @@ impl ChatWidget<'_> {
             EventMsg::ExecCommandEnd(ExecCommandEndEvent {
                 call_id,
                 exit_code,
-                duration,
                 stdout,
                 stderr,
             }) => {
@@ -400,7 +400,7 @@ impl ChatWidget<'_> {
                         exit_code,
                         stdout,
                         stderr,
-                        duration,
+                        duration: Duration::from_secs(0),
                     },
                 ));
             }
@@ -509,10 +509,6 @@ impl ChatWidget<'_> {
         self.bottom_pane
             .set_token_usage(self.token_usage.clone(), self.config.model_context_window);
     }
-
-    pub fn cursor_pos(&self, area: Rect) -> Option<(u16, u16)> {
-        self.bottom_pane.cursor_pos(area)
-    }
 }
 
 impl WidgetRef for &ChatWidget<'_> {

codex-rs/tui/src/status_indicator_widget.rs

@@ -57,7 +57,7 @@ impl StatusIndicatorWidget {
             thread::spawn(move || {
                 let mut counter = 0usize;
                 while running_clone.load(Ordering::Relaxed) {
-                    std::thread::sleep(Duration::from_millis(100));
+                    std::thread::sleep(Duration::from_millis(200));
                     counter = counter.wrapping_add(1);
                     frame_idx_clone.store(counter, Ordering::Relaxed);
                     app_event_tx_clone.send(AppEvent::RequestRedraw);
@@ -98,51 +98,46 @@ impl WidgetRef for StatusIndicatorWidget {
             .borders(Borders::LEFT)
             .border_type(BorderType::QuadrantOutside)
             .border_style(widget_style.dim());
+        // Animated 3‑dot pattern inside brackets. The *active* dot is bold
+        // white, the others are dim.
+        const DOT_COUNT: usize = 3;
         let idx = self.frame_idx.load(std::sync::atomic::Ordering::Relaxed);
-        let header_text = "Working";
-        let header_chars: Vec<char> = header_text.chars().collect();
-
-        let padding = 4usize; // virtual padding around the word for smoother loop
-        let period = header_chars.len() + padding * 2;
-        let pos = idx % period;
-
-        let has_true_color = supports_color::on_cached(supports_color::Stream::Stdout)
-            .map(|level| level.has_16m)
-            .unwrap_or(false);
-
-        // Width of the bright band (in characters).
-        let band_half_width = 2.0;
+        let phase = idx % (DOT_COUNT * 2 - 2);
+        let active = if phase < DOT_COUNT {
+            phase
+        } else {
+            (DOT_COUNT * 2 - 2) - phase
+        };
 
         let mut header_spans: Vec<Span<'static>> = Vec::new();
-        for (i, ch) in header_chars.iter().enumerate() {
-            let i_pos = i as isize + padding as isize;
-            let pos = pos as isize;
-            let dist = (i_pos - pos).abs() as f32;
 
-            let t = if dist <= band_half_width {
-                let x = std::f32::consts::PI * (dist / band_half_width);
-                0.5 * (1.0 + x.cos())
-            } else {
-                0.0
-            };
+        header_spans.push(Span::styled(
+            "Working ",
+            Style::default()
+                .fg(Color::White)
+                .add_modifier(Modifier::BOLD),
+        ));
 
-            let brightness = 0.4 + 0.6 * t;
-            let level = (brightness * 255.0).clamp(0.0, 255.0) as u8;
-            let style = if has_true_color {
+        header_spans.push(Span::styled(
+            "[",
+            Style::default()
+                .fg(Color::White)
+                .add_modifier(Modifier::BOLD),
+        ));
+
+        for i in 0..DOT_COUNT {
+            let style = if i == active {
                 Style::default()
-                    .fg(Color::Rgb(level, level, level))
+                    .fg(Color::White)
                     .add_modifier(Modifier::BOLD)
             } else {
-                // Bold makes dark gray and gray look the same, so don't use it
-                // when true color is not supported.
-                Style::default().fg(color_for_level(level))
+                Style::default().dim()
             };
-
-            header_spans.push(Span::styled(ch.to_string(), style));
+            header_spans.push(Span::styled(".", style));
         }
 
         header_spans.push(Span::styled(
-            " ",
+            "] ",
             Style::default()
                 .fg(Color::White)
                 .add_modifier(Modifier::BOLD),
@@ -194,13 +189,3 @@ impl WidgetRef for StatusIndicatorWidget {
         paragraph.render_ref(area, buf);
     }
 }
-
-fn color_for_level(level: u8) -> Color {
-    if level < 128 {
-        Color::DarkGray
-    } else if level < 192 {
-        Color::Gray
-    } else {
-        Color::White
-    }
-}