## Why
The first auto-review currently creates its Guardian child session on
demand, adding avoidable latency before the review can begin. Creating
the ordinary Guardian child during parent-session initialization lets
that child use the existing session startup WebSocket prewarm before the
first escalation. This does not introduce a Guardian-specific prewarm
mechanism.
## What changed
- initialize the existing Guardian review-session manager owned by
`Session` when a thread starts with auto-review enabled and an approval
policy that routes to Guardian
- use the standard Guardian child-session construction and the existing
session startup WebSocket prewarm
- preserve the existing reuse-key invalidation and lazy creation
fallback when startup initialization fails or the effective review
configuration changes
- add an integration test that verifies normal root-session startup
emits a Guardian `generate=false` prewarm request
## Benchmark
I compared release builds against main. Each prompt first ran a
non-escalated `sleep 3`, then requested an escalated marker command.
| binary | count | avg Guardian duration | median Guardian duration |
avg Guardian TTFT |
|---|---:|---:|---:|---:|
| origin-main | 10 | 4008.7 ms | 3949.5 ms | 3746.5 ms |
| session-fix | 10 | 2865.0 ms | 2594.0 ms | 2492.7 ms |
Guardian duration fell by 28.5% and Guardian TTFT fell by 33.5%. These
measurements cover Guardian review latency; they do not measure parent
thread-start latency.
## Why
Thread cwd and environment selections are a single logical setting in
core: updating one without the other can silently desynchronize the
next-turn execution context. This change makes that relationship
explicit in the internal thread settings flow while preserving the
existing app-server public API shape.
## What changed
- Moved the cwd/environment pair through internal
`ThreadSettingsOverrides.environment_settings` instead of a top-level
internal `cwd` field.
- Kept `thread/settings/update` public params unchanged, with app-server
translating top-level `cwd` into the paired internal settings shape.
- Moved `Op::UserInput` environment overrides into thread settings so
user turns and settings updates use the same core path.
- Updated core, app-server, MCP, memories, sample, and test callsites to
construct the paired settings shape.
## Verification
- `git diff --check`
- Local test run starting after PR creation.
## Why
Thread settings cwd overrides are expected to be resolved before they
enter core. Keeping this boundary as a plain `PathBuf` made it easy for
core/session code to keep fallback normalization and relative-path
resolution logic in places that should only receive an already-resolved
cwd.
This is intentionally the absolute-cwd-only slice: it does not change
environment selection stickiness or cwd-to-default-environment fallback
behavior.
## What changed
- Changes `ThreadSettingsOverrides.cwd`,
`CodexThreadSettingsOverrides.cwd`, and `SessionSettingsUpdate.cwd` to
use `AbsolutePathBuf`.
- Removes core-side cwd normalization/resolution from session settings
updates.
- Updates affected core/app-server test helpers and callsites to pass
existing absolute cwd values or use `abs()` helpers.
## Validation
Opening as draft so CI can start while local validation continues.
## Summary
- Add the missing additional_context field to the guardian review
Op::UserInput test initializer.
## Test plan
- just fmt
- just test -p codex-core guardian_review
- just test -p codex-core (compiles, then fails on local environment
issues: sandbox-exec Operation not permitted, missing test_stdio_server
helper binary, and unrelated timeouts)
## Summary
Clear inherited legacy `notify` from Guardian review session config,
since we should not be passing auto review threads into `notify`
targets. Keeps legacy notify payload and hook runtime behavior unchanged
for normal user turns.
## Testing
- [x] add a Guardian config regression and dedicated Guardian
integration test so review sessions cannot inherit parent notify hooks
jgershen-oai ·
pakrym-oai ·
jif-oai ·
Dylan Hurd ·