Stop hooks now receive `stop_hook_active` and enable stop hooks to loop
forever if they'd like to. In the initial hooks PR, we implemented a
simpler mechanic that the stop-blocking could only happen once in a row
- support stop hook adding a continuation prompt to add a further task
- if multiple stop-blocks happen that have continuation prompts, they
are concatenated
example run:
```
› hey :)
• Running SessionStart hook: lighting the observatory
SessionStart hook (completed)
warning: Hi, I'm a session start hook for wizard-tower (startup).
hook context: Startup context: A wimboltine stonpet is an exotic cuisine from hyperspace
• Aloha :) Happy to jam with you. What are we building today?
• Running Stop hook: updating the guards
Stop hook (blocked)
warning: Wizard Tower Stop hook continuing conversation
feedback: cook the stonpet
• Aloha, here’s the hyperspace move for cooking a wimboltine stonpet:
1. Sear the stonpet in a hot pan with moon-oil until the edges shimmer.
2. Add star-lime, black salt, and a little fermented nebula paste.
3. Lower the heat and let it braise for 8 cosmic minutes with a splash of comet broth.
4. Finish with sky herbs and serve over warm asteroid rice.
The vibe: crispy outside, tender center, deep interdimensional savor.
• Running Stop hook: updating the guards
Stop hook (completed)
warning: Wizard Tower Stop hook saw a second pass and stayed calm to avoid a loop.
```
.codex/config.toml
```
[features]
codex_hooks = true
```
.codex/hooks.json
```
{
"hooks": {
"SessionStart": [
{
"matcher": "startup|resume",
"hooks": [
{
"type": "command",
"command": "/usr/bin/python3 .codex/hooks/session_start_demo.py",
"timeoutSec": 10,
"statusMessage": "lighting the observatory"
}
]
}
],
"Stop": [
{
"hooks": [
{
"type": "command",
"command": "/usr/bin/python3 .codex/hooks/stop_demo_block.py",
"timeoutSec": 10,
"statusMessage": "updating the guards"
}
]
}
]
}
}
```
.codex/hooks/session_start_demo.py
```
#!/usr/bin/env python3
import json
import sys
from pathlib import Path
def main() -> int:
payload = json.load(sys.stdin)
cwd = Path(payload.get("cwd", ".")).name or "wizard-tower"
source = payload.get("source", "startup")
source_label = "resume" if source == "resume" else "startup"
source_prefix = (
"Resume context:"
if source == "resume"
else "Startup context:"
)
output = {
"systemMessage": (
f"Hi, I'm a session start hook for {cwd} ({source_label})."
),
"hookSpecificOutput": {
"hookEventName": "SessionStart",
"additionalContext": (
f"{source_prefix} A wimboltine stonpet is an exotic cuisine from hyperspace"
),
},
}
print(json.dumps(output))
return 0
if __name__ == "__main__":
raise SystemExit(main())
```
.codex/hooks/stop_demo_block.py
```
#!/usr/bin/env python3
import json
import sys
def main() -> int:
payload = json.load(sys.stdin)
stop_hook_active = payload.get("stop_hook_active", False)
last_assistant_message = payload.get("last_assistant_message") or ""
char_count = len(last_assistant_message.strip())
if stop_hook_active:
system_message = (
"Wizard Tower Stop hook saw a second pass and stayed calm to avoid a loop."
)
print(json.dumps({"systemMessage": system_message}))
else:
system_message = (
f"Wizard Tower Stop hook continuing conversation"
)
print(json.dumps({"systemMessage": system_message, "decision": "block", "reason": "cook the stonpet"}))
return 0
if __name__ == "__main__":
raise SystemExit(main())
```
(Experimental)
This PR adds a first MVP for hooks, with SessionStart and Stop
The core design is:
- hooks live in a dedicated engine under codex-rs/hooks
- each hook type has its own event-specific file
- hook execution is synchronous and blocks normal turn progression while
running
- matching hooks run in parallel, then their results are aggregated into
a normalized HookRunSummary
On the AppServer side, hooks are exposed as operational metadata rather
than transcript-native items:
- new live notifications: hook/started, hook/completed
- persisted/replayed hook results live on Turn.hookRuns
- we intentionally did not add hook-specific ThreadItem variants
Hooks messages are not persisted, they remain ephemeral. The context
changes they add are (they get appended to the user's prompt)
## Why
The `notify` hook payload did not identify which Codex client started
the turn. That meant downstream notification hooks could not distinguish
between completions coming from the TUI and completions coming from
app-server clients such as VS Code or Xcode. Now that the Codex App
provides its own desktop notifications, it would be nice to be able to
filter those out.
This change adds that context without changing the existing payload
shape for callers that do not know the client name, and keeps the new
end-to-end test cross-platform.
## What changed
- added an optional top-level `client` field to the legacy `notify` JSON
payload
- threaded that value through `core` and `hooks`; the internal session
and turn state now carries it as `app_server_client_name`
- set the field to `codex-tui` for TUI turns
- captured `initialize.clientInfo.name` in the app server and applied it
to subsequent turns before dispatching hooks
- replaced the notify integration test hook with a `python3` script so
the test does not rely on Unix shell permissions or `bash`
- documented the new field in `docs/config.md`
## Testing
- `cargo test -p codex-hooks`
- `cargo test -p codex-tui`
- `cargo test -p codex-app-server
suite::v2::initialize::turn_start_notify_payload_includes_initialize_client_name
-- --exact --nocapture`
- `cargo test -p codex-core` (`src/lib.rs` passed; `core/tests/all.rs`
still has unrelated existing failures in this environment)
## Docs
The public config reference on `developers.openai.com/codex` should
mention that the legacy `notify` payload may include a top-level
`client` field. The TUI reports `codex-tui`, and the app server reports
`initialize.clientInfo.name` when it is available.
Summary
- move `core/src/hooks` implementation into a new `codex-hooks` crate
with its own manifest
- update `codex-rs` workspace and `codex-core` crate to depend on the
extracted `hooks` crate and wire up the shared APIs
- ensure references, modules, and lockfile reflect the new crate layout
Testing
- Not run (not requested)
