## Why
`--profile-v2 <name>` gives launchers and runtime entry points a named
profile config without making each profile duplicate the base user
config. The base `$CODEX_HOME/config.toml` still loads first, then
`$CODEX_HOME/<name>.config.toml` layers above it and becomes the active
writable user config for that session.
That keeps shared defaults, plugin/MCP setup, and managed/user
constraints in one place while letting a named profile override only the
pieces that need to differ.
## What Changed
- Added the shared `--profile-v2 <name>` runtime option with validated
plain names, now represented by `ProfileV2Name`.
- Extended config layer state so the base user config and selected
profile config are both `User` layers; APIs expose the active user layer
and merged effective user config.
- Threaded profile selection through runtime entry points: `codex`,
`codex exec`, `codex review`, `codex resume`, `codex fork`, and `codex
debug prompt-input`.
- Made user-facing config writes go to the selected profile file when
active, including TUI/settings persistence, app-server config writes,
and MCP/app tool approval persistence.
- Made plugin, marketplace, MCP, hooks, and config reload paths read
from the merged user config so base and profile layers both participate.
- Updated app-server config layer schemas to mark profile-backed user
layers.
## Limits
`--profile-v2` is still rejected for config-management subcommands such
as feature, MCP, and marketplace edits. Those paths remain tied to the
base `config.toml` until they have explicit profile-selection semantics.
Some adjacent background writes may still update base or global state
rather than the selected profile:
- marketplace auto-upgrade metadata
- automatic MCP dependency installs from skills
- remote plugin sync or uninstall config edits
- personality migration marker/default writes
## Verification
Added targeted coverage for profile name validation, layer
ordering/merging, selected-profile writes, app-server config writes,
session hot reload, plugin config merging, hooks/config fixture updates,
and MCP/app approval persistence.
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
Codex intentionally ignores unknown `config.toml` fields by default so
older and newer config files keep working across versions. That leniency
also makes typo detection hard because misspelled or misplaced keys
disappear silently.
This change adds an opt-in strict config mode so users and tooling can
fail fast on unrecognized config fields without changing the default
permissive behavior.
This feature is possible because `serde_ignored` exposes the exact
signal Codex needs: it lets Codex run ordinary Serde deserialization
while recording fields Serde would otherwise ignore. That avoids
requiring `#[serde(deny_unknown_fields)]` across every config type and
keeps strict validation opt-in around the existing config model.
## What Changed
### Added strict config validation
- Added `serde_ignored`-based validation for `ConfigToml` in
`codex-rs/config/src/strict_config.rs`.
- Combined `serde_ignored` with `serde_path_to_error` so strict mode
preserves typed config error paths while also collecting fields Serde
would otherwise ignore.
- Added strict-mode validation for unknown `[features]` keys, including
keys that would otherwise be accepted by `FeaturesToml`'s flattened
boolean map.
- Kept typed config errors ahead of ignored-field reporting, so
malformed known fields are reported before unknown-field diagnostics.
- Added source-range diagnostics for top-level and nested unknown config
fields, including non-file managed preference source names.
### Kept parsing single-pass per source
- Reworked file and managed-config loading so strict validation reuses
the already parsed `TomlValue` for that source.
- For actual config files and managed config strings, the loader now
reads once, parses once, and validates that same parsed value instead of
deserializing multiple times.
- Validated `-c` / `--config` override layers with the same
base-directory context used for normal relative-path resolution, so
unknown override keys are still reported when another override contains
a relative path.
### Scoped `--strict-config` to config-heavy entry points
- Added support for `--strict-config` on the main config-loading entry
points where it is most useful:
- `codex`
- `codex resume`
- `codex fork`
- `codex exec`
- `codex review`
- `codex mcp-server`
- `codex app-server` when running the server itself
- the standalone `codex-app-server` binary
- the standalone `codex-exec` binary
- Commands outside that set now reject `--strict-config` early with
targeted errors instead of accepting it everywhere through shared CLI
plumbing.
- `codex app-server` subcommands such as `proxy`, `daemon`, and
`generate-*` are intentionally excluded from the first rollout.
- When app-server strict mode sees invalid config, app-server exits with
the config error instead of logging a warning and continuing with
defaults.
- Introduced a dedicated `ReviewCommand` wrapper in `codex-rs/cli`
instead of extending shared `ReviewArgs`, so `--strict-config` stays on
the outer config-loading command surface and does not become part of the
reusable review payload used by `codex exec review`.
### Coverage
- Added tests for top-level and nested unknown config fields, unknown
`[features]` keys, typed-error precedence, source-location reporting,
and non-file managed preference source names.
- Added CLI coverage showing invalid `--enable`, invalid `--disable`,
and unknown `-c` overrides still error when `--strict-config` is
present, including compound-looking feature names such as
`multi_agent_v2.subagent_usage_hint_text`.
- Added integration coverage showing both `codex app-server
--strict-config` and standalone `codex-app-server --strict-config` exit
with an error for unknown config fields instead of starting with
fallback defaults.
- Added coverage showing unsupported command surfaces reject
`--strict-config` with explicit errors.
## Example Usage
Run Codex with strict config validation enabled:
```shell
codex --strict-config
```
Strict config mode is also available on the supported config-heavy
subcommands:
```shell
codex --strict-config exec "explain this repository"
codex review --strict-config --uncommitted
codex mcp-server --strict-config
codex app-server --strict-config --listen off
codex-app-server --strict-config --listen off
```
For example, if `~/.codex/config.toml` contains a typo in a key name:
```toml
model = "gpt-5"
approval_polic = "on-request"
```
then `codex --strict-config` reports the misspelled key instead of
silently ignoring it. The path is shortened to `~` here for readability:
```text
$ codex --strict-config
Error loading config.toml:
~/.codex/config.toml:2:1: unknown configuration field `approval_polic`
|
2 | approval_polic = "on-request"
| ^^^^^^^^^^^^^^
```
Without `--strict-config`, Codex keeps the existing permissive behavior
and ignores the unknown key.
Strict config mode also validates ad-hoc `-c` / `--config` overrides:
```text
$ codex --strict-config -c foo=bar
Error: unknown configuration field `foo` in -c/--config override
$ codex --strict-config -c features.foo=true
Error: unknown configuration field `features.foo` in -c/--config override
```
Invalid feature toggles are rejected too, including values that look
like nested config paths:
```text
$ codex --strict-config --enable does_not_exist
Error: Unknown feature flag: does_not_exist
$ codex --strict-config --disable does_not_exist
Error: Unknown feature flag: does_not_exist
$ codex --strict-config --enable multi_agent_v2.subagent_usage_hint_text
Error: Unknown feature flag: multi_agent_v2.subagent_usage_hint_text
```
Unsupported commands reject the flag explicitly:
```text
$ codex --strict-config cloud list
Error: `--strict-config` is not supported for `codex cloud`
```
## Verification
The `codex-cli` `strict_config` tests cover invalid `--enable`, invalid
`--disable`, the compound `multi_agent_v2.subagent_usage_hint_text`
case, unknown `-c` overrides, app-server strict startup failure through
`codex app-server`, and rejection for unsupported commands such as
`codex cloud`, `codex mcp`, `codex remote-control`, and `codex
app-server proxy`.
The config and config-loader tests cover unknown top-level fields,
unknown nested fields, unknown `[features]` keys, source-location
reporting, non-file managed config sources, and `-c` validation for keys
such as `features.foo`.
The app-server test suite covers standalone `codex-app-server
--strict-config` startup failure for an unknown config field.
## Documentation
The Codex CLI docs on developers.openai.com/codex should mention
`--strict-config` as an opt-in validation mode for supported
config-heavy entry points once this ships.
# Overview
MCP refreshes were rebuilding active threads from fresh disk-backed
config only, which dropped thread-start session overlays such as
app-injected MCP servers. This keeps refreshes current with disk config
while preserving the thread-local config that only the active thread
knows about.
# Changes
- Rebuild refreshed config per active thread using that thread's current
`cwd`, rather than fanning out one app-server config to every thread.
- Preserve each thread's `SessionFlags` layer while replacing reloadable
config layers with freshly loaded config, then derive the MCP refresh
payload from the rebuilt result.
- Move MCP refresh orchestration into app-server so manual refreshes
fail loudly while background refreshes remain best-effort, and route
plugin-triggered refreshes through the same per-thread reload path.
- Add regression coverage for session overlays, fresh project config,
plugin-derived MCP config, current requirements, and strict vs
best-effort refresh behavior.
# Verification
- Passed focused Rust coverage for the thread-config rebuild behavior
and deferred MCP refresh flow, plus `cargo test -p codex-app-server
--lib`.
- Verified end to end in the Codex dev app against the locally built
CLI: registered an MCP via thread config, verified that it could be used
successfully before refresh, manually triggered MCP refresh, and
verified that it continued to be available afterward.
# Why
Requirements support host-specific
`remote_sandbox_config.hostname_patterns`, but config loading previously
resolved and passed the system hostname through every config-loading
path even when no requirements layer used `remote_sandbox_config`. On
machines where hostname lookup is slow, startup and app-server config
reads paid for a feature that was not active.
We only need the hostname when a requirements layer actually declares
`remote_sandbox_config`, so this moves hostname resolution to the single
requirements merge point and keeps all other config callers unaware of
hostname matching.
# What
- Removed the eager `host_name` plumbing from
`load_config_layers_state`, `load_requirements_toml`, `ConfigBuilder`,
app-server `ConfigManager`, network proxy loading, and related call
sites.
- Resolve the hostname inside
`merge_requirements_with_remote_sandbox_config` only when the incoming
requirements contain `remote_sandbox_config`.
## Why
Config loading had become split across crates: `codex-config` owned the
config types and merge logic, while `codex-core` still owned the loader
that assembled the layer stack. This change consolidates that
responsibility in `codex-config`, so the crate that defines config
behavior also owns how configs are discovered and loaded.
To make that move possible without reintroducing the old dependency
cycle, the shell-environment policy types and helpers that
`codex-exec-server` needs now live in `codex-protocol` instead of
flowing through `codex-config`.
This also makes the migrated loader tests more deterministic on machines
that already have managed or system Codex config installed by letting
tests override the system config and requirements paths instead of
reading the host's `/etc/codex`.
## What Changed
- moved the config loader implementation from `codex-core` into
`codex-config::loader` and deleted the old `core::config_loader` module
instead of leaving a compatibility shim
- moved shell-environment policy types and helpers into
`codex-protocol`, then updated `codex-exec-server` and other downstream
crates to import them from their new home
- updated downstream callers to use loader/config APIs from
`codex-config`
- added test-only loader overrides for system config and requirements
paths so loader-focused tests do not depend on host-managed config state
- cleaned up now-unused dependency entries and platform-specific cfgs
that were surfaced by post-push CI
## Testing
- `cargo test -p codex-config`
- `cargo test -p codex-core config_loader_tests::`
- `cargo test -p codex-protocol -p codex-exec-server -p
codex-cloud-requirements -p codex-rmcp-client --lib`
- `cargo test --lib -p codex-app-server-client -p codex-exec`
- `cargo test --no-run --lib -p codex-app-server`
- `cargo test -p codex-linux-sandbox --lib`
- `cargo shear`
- `just bazel-lock-check`
## Notes
- I did not chase unrelated full-suite failures outside the migrated
loader surface.
- `cargo test -p codex-core --lib` still hits unrelated proxy-sensitive
failures on this machine, and Windows CI still shows unrelated
long-running/timeouting test noise outside the loader migration itself.
## Why
App-server needs a way to fetch thread-scoped config from the remote
thread config service when the user config opts into that behavior. This
mirrors the existing experimental remote thread store endpoint while
keeping local/noop behavior as the default.
Startup paths also need to avoid silently dropping the remote config
endpoint after the first config load. The stdio app-server path
discovers the endpoint from the initial config and installs the real
thread config loader for later config builds, while in-process clients
used by TUI/exec now select the same remote loader directly from their
provided config.
## What changed
- Added `experimental_thread_config_endpoint` to `ConfigToml`, `Config`,
and `core/config.schema.json`.
- Added config parsing coverage for the new setting.
- Updated app-server startup to select `RemoteThreadConfigLoader` from
the initially loaded config, falling back to `NoopThreadConfigLoader`
when unset.
- Let `ConfigManager` replace its thread config loader after startup
discovery so later config loads use the selected loader.
- Updated in-process app-server client startup to pass
`RemoteThreadConfigLoader` when its config has
`experimental_thread_config_endpoint` set.
## Verification
- Added `experimental_thread_config_endpoint_loads_from_config_toml`.
- Added
`runtime_start_args_use_remote_thread_config_loader_when_configured`.
- Ran `cargo check -p codex-app-server --lib`.
- Ran `cargo test -p codex-app-server-client`.