## Description
Adding an extension to the spec that exposes the turn_id to hook
scripts. This is a codex-specific mechanic that allows connecting the
hook runs with particular turns
## Testing
hooks config / sample hooks to use. Extract this, rename codex ->
.codex, and place this into a repo or your home folder. It includes:
config.toml that enables hooks, hooks.json, and sample python hooks:
[codex.zip](https://github.com/user-attachments/files/26102671/codex.zip)
example run (note the turn_ids change between turns):
```
› hello
• 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
• Running UserPromptSubmit hook: lighting the observatory lanterns
UserPromptSubmit hook (completed)
warning: wizard-tower UserPromptSubmit demo inspected: hello for turn: 019d036d-c7fa-72d2-b6fd-
78878bfe34e4
hook context: Wizard Tower UserPromptSubmit demo fired. For this reply only, include the exact
phrase 'observatory lanterns lit' near the end.
• Aloha! Grateful to be here and ready to build with you. Show me what you want to tackle in wizard-
tower, and we’ll surf the next wave together. observatory lanterns lit
• Running Stop hook: back to shore
Stop hook (completed)
warning: Wizard Tower Stop hook reviewed the completed reply (170 chars) for turn: 019d036d-c7fa-
72d2-b6fd-78878bfe34e4
› what's a stonpet?
• Running UserPromptSubmit hook: lighting the observatory lanterns
UserPromptSubmit hook (completed)
warning: wizard-tower UserPromptSubmit demo inspected: what's a stonpet? for turn: 019d036e-3164-
72c3-a170-98925564c4fc
hook context: Wizard Tower UserPromptSubmit demo fired. For this reply only, include the exact
phrase 'observatory lanterns lit' near the end.
• A stonpet isn’t a standard real-world word, brah. In our shared context here, a wimboltine stonpet
is an exotic cuisine from hyperspace, so “stonpet” sounds like the dish or food itself.
If you want, we can totally invent the lore for it next. observatory lanterns lit
• Running Stop hook: back to shore
Stop hook (completed)
warning: Wizard Tower Stop hook reviewed the completed reply (271 chars) for turn: 019d036e-3164-
72c3-a170-98925564c4fc
```
(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)