# Why
`plugin_hook_sources_run_with_plugin_env_and_plugin_source` can still
fail on Windows after the earlier file-based assertion cleanup because
the hook process itself occasionally exceeds the old 5s timeout under CI
load. When that happens, the hook run ends as `Failed` before the test
can inspect its structured output.
The Windows Bazel failure showed the hook run itself failing after
nearly 8 seconds:
```text
---- engine::tests::plugin_hook_sources_run_with_plugin_env_and_plugin_source stdout ----
thread 'engine::tests::plugin_hook_sources_run_with_plugin_env_and_plugin_source' panicked at hooks/src\engine\mod_tests.rs:428:5:
assertion failed: `(left == right)`
Diff < left / right > :
<Failed
>Completed
...
test result: FAILED. 78 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 7.96s
```
# What
- raise the flaky plugin hook env test timeout from 5s to 10s so it
matches the other executed hook tests in this module
# Validation
- `cargo test -p codex-hooks`
The test was flaky because it was checking the right thing in a
roundabout way.
What it wanted to prove:
- plugin hooks receive the right environment variables.
What it actually did:
1. Run a plugin hook.
2. Have that hook write those env vars into a temporary `env.json` file.
3. After the hook finished, read `env.json` back from disk.
On Windows, that last file was sometimes not there when the test tried
to read it, so the test failed with `read env log: file not found`. The
hook system itself was not what the test failure was directly proving;
the test was failing on the extra filesystem side effect it introduced.
The fix is to stop using a temp file as the proof mechanism. The hook
now prints the env values in its normal structured output, and the test
asserts on the output that the hook engine already captures. So we still
verify the same behavior, but without depending on a separate file being
created and read back correctly on Windows.
## Why
Plugins can bundle lifecycle hooks, but Codex previously only discovered
hooks from user, project, and managed config layers. This adds the
plugin discovery and runtime plumbing needed for plugin-bundled hooks
while keeping execution behind the `plugin_hooks` feature flag.
## What
- Discovers plugin hook sources from each plugin's default
`hooks/hooks.json`.
- Supports `plugin.json` manifest `hooks` entries as either relative
paths or inline hook objects.
- Plumbs discovered plugin hook sources through plugin loading into the
hook runtime when `plugin_hooks` is enabled.
- Marks plugin-originated hook runs as `HookSource::Plugin`.
- Injects `PLUGIN_ROOT` and `CLAUDE_PLUGIN_ROOT` into plugin hook
command environments.
- Updates generated schemas and hook source metadata for the plugin hook
source.
## Stack
1. This PR - openai/codex#19705
2. openai/codex#19778
3. openai/codex#19840
4. openai/codex#19882
## Reviewer Notes
- Core logic is in `codex-rs/core-plugins/src/loader.rs` and
`codex-rs/hooks/src/engine/discovery.rs`
- Moved existing / adding new tests to
`codex-rs/core-plugins/src/loader_tests.rs` hence the large diff there
- Otherwise mostly plumbing and minor schema updates
### Core Changes
The `codex-rs/core` changes are limited to wiring plugin hook support
into existing core flows:
- `core/src/session/session.rs` conditionally pulls effective plugin
hook sources and plugin hook load warnings from `PluginsManager` when
`plugin_hooks` is enabled, then passes them into `HooksConfig`.
- `core/src/hook_runtime.rs` adds the `plugin` metric tag for
`HookSource::Plugin`.
- `core/config.schema.json` picks up the new `plugin_hooks` feature
flag, and `core/src/plugins/manager_tests.rs` updates fixtures for the
added plugin hook fields.
---------
Co-authored-by: Codex <noreply@openai.com>
## Summary
Lifecycle hooks currently treat `PreToolUse`, `PostToolUse`, and
`PermissionRequest` as Bash-only flows
- hook schema constrains `tool_name` to `Bash`
- hook input assumes a command-shaped `tool_input`
- core hook dispatch path passes only shell command strings
That means hooks cannot target MCP tools even though MCP tool names are
model-visible and stable
This change generalizes those hook paths so they can match and receive
payloads for MCP tools while preserving the existing Bash behavior.
## Reviewer Notes
I think these are the key files
- `codex-rs/core/src/tools/handlers/mcp.rs`
- `codex-rs/core/src/mcp_tool_call.rs`
Otherwise the changes across apply_patch, shell, and unified_exec are
mainly to rewire everything to be `tool_input` based instead of just
`command` so that it'll make sense for MCP tools.
## Changes
- Allow `PreToolUse`, `PostToolUse`, and `PermissionRequest` hook inputs
to carry arbitrary `tool_name` and `tool_input` values instead of
hard-coding `Bash` and command-only payloads.
- Add MCP hook payload support through `McpHandler`, using the
model-visible tool name from `ToolInvocation` and the raw MCP arguments
as `tool_input`.
- Include MCP tool responses in `PostToolUse` by serializing
`McpToolOutput` into the hook response payload.
- Run `PermissionRequest` hooks for MCP approval requests after
remembered approval checks and before falling back to user-facing MCP
elicitation.
- Preserve exact matching for literal hook matchers like `Bash` and
`mcp__memory__create_entities`, while keeping regex matcher support for
patterns like `mcp__memory__.*` and `mcp__.*__write.*`.
---------
Co-authored-by: Andrei Eternal <eternal@openai.com>
Co-authored-by: Codex <noreply@openai.com>
## Summary
Support the existing hooks schema in inline TOML so hooks can be
configured from both `config.toml` and enterprise-managed
`requirements.toml` without requiring a separate `hooks.json` payload.
This gives enterprise admins a way to ship managed hook policy through
the existing requirements channel while still leaving script delivery to
MDM or other device-management tooling, and it keeps `hooks.json`
working unchanged for existing users.
This also lays the groundwork for follow-on managed filtering work such
as #15937, while continuing to respect project trust gating from #14718.
It does **not** implement `allow_managed_hooks_only` itself.
NOTE: yes, it's a bit unfortunate that the toml isn't formatted as
closely as normal to our default styling. This is because we're trying
to stay compatible with the spec for plugins/hooks that we'll need to
support & the main usecase here is embedding into requirements.toml
## What changed
- moved the shared hook serde model out of `codex-rs/hooks` into
`codex-rs/config` so the same schema can power `hooks.json`, inline
`config.toml` hooks, and managed `requirements.toml` hooks
- added `hooks` support to both `ConfigToml` and
`ConfigRequirementsToml`, including requirements-side `managed_dir` /
`windows_managed_dir`
- treated requirements-managed hooks as one constrained value via
`Constrained`, so managed hook policy is merged atomically and cannot
drift across requirement sources
- updated hook discovery to load requirements-managed hooks first, then
per-layer `hooks.json`, then per-layer inline TOML hooks, with a warning
when a single layer defines both representations
- threaded managed hook metadata through discovered handlers and exposed
requirements hooks in app-server responses, generated schemas, and
`/debug-config`
- added hook/config coverage in `codex-rs/config`, `codex-rs/hooks`,
`codex-rs/core/src/config_loader/tests.rs`, and
`codex-rs/core/tests/suite/hooks.rs`
## Testing
- `cargo test -p codex-config`
- `cargo test -p codex-hooks`
- `cargo test -p codex-app-server config_api`
## Documentation
Companion updates are needed in the developers website repo for:
- the hooks guide
- the config reference, sample, basic, and advanced pages
- the enterprise managed configuration guide
---------
Co-authored-by: Michael Bolin <mbolin@openai.com>
Fixes https://github.com/openai/codex/issues/16732.
## Why
`apply_patch` is Codex's primary file edit path, but it was not emitting
`PreToolUse` or `PostToolUse` hook events. That meant hook-based policy,
auditing, and write coordination could observe shell commands while
missing the actual file mutation performed by `apply_patch`.
The issue also exposed that the hook runtime serialized command hook
payloads with `tool_name: "Bash"` unconditionally. Even if `apply_patch`
supplied hook payloads, hooks would either fail to match it directly or
receive misleading stdin that identified the edit as a Bash tool call.
## What Changed
- Added `PreToolUse` and `PostToolUse` payload support to
`ApplyPatchHandler`.
- Exposed the raw patch body as `tool_input.command` for both
JSON/function and freeform `apply_patch` calls.
- Taught tool hook payloads to carry a handler-supplied hook-facing
`tool_name`.
- Preserved existing shell compatibility by continuing to emit `Bash`
for shell-like tools.
- Serialized the selected hook `tool_name` into hook stdin instead of
hardcoding `Bash`.
- Relaxed the generated hook command input schema so `tool_name` can
represent tools other than `Bash`.
## Verification
Added focused handler coverage for:
- JSON/function `apply_patch` calls producing a `PreToolUse` payload.
- Freeform `apply_patch` calls producing a `PreToolUse` payload.
- Successful `apply_patch` output producing a `PostToolUse` payload.
- Shell and `exec_command` handlers continuing to expose `Bash`.
Added end-to-end hook coverage for:
- A `PreToolUse` hook matching `^apply_patch$` blocking the patch before
the target file is created.
- A `PostToolUse` hook matching `^apply_patch$` receiving the patch
input and tool response, then adding context to the follow-up model
request.
- Non-participating tools such as the plan tool continuing not to emit
`PreToolUse`/`PostToolUse` hook events.
Also validated manually with a live `codex exec` smoke test using an
isolated temp workspace and temp `CODEX_HOME`. The smoke test confirmed
that a real `apply_patch` edit emits `PreToolUse`/`PostToolUse` with
`tool_name: "apply_patch"`, a shell command still emits `tool_name:
"Bash"`, and a denying `PreToolUse` hook prevents the blocked patch file
from being created.
## Why
We need `PermissionRequest` hook support!
Also addresses:
- https://github.com/openai/codex/issues/16301
- run a script on Hook to do things like play a sound to draw attention
but actually no-op so user can still approve
- can omit the `decision` object from output or just have the script
exit 0 and print nothing
- https://github.com/openai/codex/issues/15311
- let the script approve/deny on its own
- external UI what will run on Hook and relay decision back to codex
## Reviewer Note
There's a lot of plumbing for the new hook, key files to review are:
- New hook added in `codex-rs/hooks/src/events/permission_request.rs`
- Wiring for network approvals
`codex-rs/core/src/tools/network_approval.rs`
- Wiring for tool orchestrator `codex-rs/core/src/tools/orchestrator.rs`
- Wiring for execve
`codex-rs/core/src/tools/runtimes/shell/unix_escalation.rs`
## What
- Wires shell, unified exec, and network approval prompts into the
`PermissionRequest` hook flow.
- Lets hooks allow or deny approval prompts; quiet or invalid hooks fall
back to the normal approval path.
- Uses `tool_input.description` for user-facing context when it helps:
- shell / `exec_command`: the request justification, when present
- network approvals: `network-access <domain>`
- Uses `tool_name: Bash` for shell, unified exec, and network approval
permission-request hooks.
- For network approvals, passes the originating command in
`tool_input.command` when there is a single owning call; otherwise falls
back to the synthetic `network-access ...` command.
<details>
<summary>Example `PermissionRequest` hook input for a shell
approval</summary>
```json
{
"session_id": "<session-id>",
"turn_id": "<turn-id>",
"transcript_path": "/path/to/transcript.jsonl",
"cwd": "/path/to/cwd",
"hook_event_name": "PermissionRequest",
"model": "gpt-5",
"permission_mode": "default",
"tool_name": "Bash",
"tool_input": {
"command": "rm -f /tmp/example"
}
}
```
</details>
<details>
<summary>Example `PermissionRequest` hook input for an escalated
`exec_command` request</summary>
```json
{
"session_id": "<session-id>",
"turn_id": "<turn-id>",
"transcript_path": "/path/to/transcript.jsonl",
"cwd": "/path/to/cwd",
"hook_event_name": "PermissionRequest",
"model": "gpt-5",
"permission_mode": "default",
"tool_name": "Bash",
"tool_input": {
"command": "cp /tmp/source.json /Users/alice/export/source.json",
"description": "Need to copy a generated file outside the workspace"
}
}
```
</details>
<details>
<summary>Example `PermissionRequest` hook input for a network
approval</summary>
```json
{
"session_id": "<session-id>",
"turn_id": "<turn-id>",
"transcript_path": "/path/to/transcript.jsonl",
"cwd": "/path/to/cwd",
"hook_event_name": "PermissionRequest",
"model": "gpt-5",
"permission_mode": "default",
"tool_name": "Bash",
"tool_input": {
"command": "curl http://codex-network-test.invalid",
"description": "network-access http://codex-network-test.invalid"
}
}
```
</details>
## Follow-ups
- Implement the `PermissionRequest` semantics for `updatedInput`,
`updatedPermissions`, `interrupt`, and suggestions /
`permission_suggestions`
- Add `PermissionRequest` support for the `request_permissions` tool
path
---------
Co-authored-by: Codex <noreply@openai.com>
# Why
Add product analytics for hook handler executions so we can understand
which hooks are running, where they came from, and whether they
completed, failed, stopped, or blocked work.
# What
- add the new `codex_hook_run` analytics event and payload plumbing in
`codex-rs/analytics`
- emit hook-run analytics from the shared hook completion path in
`codex-rs/core`
- classify hook source from the loaded hook path as `system`, `user`,
`project`, or `unknown`
```
{
"event_type": "codex_hook_run",
"event_params": {
"thread_id": "string",
"turn_id": "string",
"model_slug": "string",
"hook_name": "string, // any HookEventName
"hook_source": "system | user | project | unknown",
"status": "completed | failed | stopped | blocked"
}
}
```
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
`argument-comment-lint` was green in CI even though the repo still had
many uncommented literal arguments. The main gap was target coverage:
the repo wrapper did not force Cargo to inspect test-only call sites, so
examples like the `latest_session_lookup_params(true, ...)` tests in
`codex-rs/tui_app_server/src/lib.rs` never entered the blocking CI path.
This change cleans up the existing backlog, makes the default repo lint
path cover all Cargo targets, and starts rolling that stricter CI
enforcement out on the platform where it is currently validated.
## What changed
- mechanically fixed existing `argument-comment-lint` violations across
the `codex-rs` workspace, including tests, examples, and benches
- updated `tools/argument-comment-lint/run-prebuilt-linter.sh` and
`tools/argument-comment-lint/run.sh` so non-`--fix` runs default to
`--all-targets` unless the caller explicitly narrows the target set
- fixed both wrappers so forwarded cargo arguments after `--` are
preserved with a single separator
- documented the new default behavior in
`tools/argument-comment-lint/README.md`
- updated `rust-ci` so the macOS lint lane keeps the plain wrapper
invocation and therefore enforces `--all-targets`, while Linux and
Windows temporarily pass `-- --lib --bins`
That temporary CI split keeps the stricter all-targets check where it is
already cleaned up, while leaving room to finish the remaining Linux-
and Windows-specific target-gated cleanup before enabling
`--all-targets` on those runners. The Linux and Windows failures on the
intermediate revision were caused by the wrapper forwarding bug, not by
additional lint findings in those lanes.
## Validation
- `bash -n tools/argument-comment-lint/run.sh`
- `bash -n tools/argument-comment-lint/run-prebuilt-linter.sh`
- shell-level wrapper forwarding check for `-- --lib --bins`
- shell-level wrapper forwarding check for `-- --tests`
- `just argument-comment-lint`
- `cargo test` in `tools/argument-comment-lint`
- `cargo test -p codex-terminal-detection`
## Follow-up
- Clean up remaining Linux-only target-gated callsites, then switch the
Linux lint lane back to the plain wrapper invocation.
- Clean up remaining Windows-only target-gated callsites, then switch
the Windows lint lane back to the plain wrapper invocation.
CHAINED PR - note that base is eternal/hooks-pretooluse-bash, not main
-- so the following PR should be first
Matching post-tool hook to the pre-tool functionality here:
https://github.com/openai/codex/pull/15211
So, PreToolUse calls for plain shell calls, allows blocking. This
PostToolUse call runs after the command executed
example run:
```
› as a test, run in parallel the following commands:
- echo 'one'
- echo '[block-pre-tool-use]'
- echo '[block-post-tool-use]'
⚠ MCP startup incomplete (failed: notion, linear)
• Cruising through those three commands in parallel now, and I’ll share the exact outputs right after
they land.
• Running PreToolUse hook: checking the observatory runes
• Running PreToolUse hook: checking the observatory runes
• Running PreToolUse hook: checking the observatory runes
PreToolUse hook (blocked)
warning: wizard-tower PreToolUse demo blocked a Bash command on purpose.
feedback: PreToolUse demo blocked the command. Remove [block-pre-tool-use] to continue.
PreToolUse hook (completed)
warning: wizard-tower PreToolUse demo inspected Bash: echo 'one'
PreToolUse hook (completed)
warning: wizard-tower PreToolUse demo inspected Bash: echo '[block-post-tool-use]'
• Ran echo '[block-post-tool-use]'
└ [block-post-tool-use]
• Ran echo 'one'
└ one
• Running PostToolUse hook: reading the observatory aftermath
• Running PostToolUse hook: reading the observatory aftermath
PostToolUse hook (blocked)
warning: wizard-tower PostToolUse demo blocked the Bash follow-through on purpose.
feedback: PostToolUse demo blocked the result after execution. Remove [block-post-tool-use] to
continue.
PostToolUse hook (completed)
warning: wizard-tower PostToolUse demo inspected Bash: echo 'one'
hook context: PostToolUse demo saw the Bash result. Response preview: one
──────────────────────────────────────────────────────────────────────────────────────────────────────
• Ran them in parallel. Little wave report:
- echo 'one' completed and returned one.
- echo '[block-pre-tool-use]' was blocked before execution by the PreToolUse hook.
- echo '[block-post-tool-use]' ran, but its result was blocked afterward by the PostToolUse hook.
The hook messages were:
- PreToolUse demo blocked the command. Remove [block-pre-tool-use] to continue.
- PostToolUse demo blocked the result after execution. Remove [block-post-tool-use] to continue.
› for the blocked messages (correctly blocked in this test) did the tool output land back into
context?
• Yeah, from this run:
- PreToolUse block: the command itself did not execute, so no command output landed in context. Only
the block message did.
- PostToolUse block: the command did execute, but the actual stdout did not come back into context.
Only the post-tool block message did.
So the blocked notifications landed in context, but the blocked command payloads themselves did not.
Nice clean guardrail, aloha.
```
- add `PreToolUse` hook for bash-like tool execution only at first
- block shell execution before dispatch with deny-only hook behavior
- introduces common.rs matcher framework for matching when hooks are run
example run:
```
› run three parallel echo commands, and the second one should echo "[block-pre-tool-use]" as a test
• Running the three echo commands in parallel now and I’ll report the output directly.
• Running PreToolUse hook: name for demo pre tool use hook
• Running PreToolUse hook: name for demo pre tool use hook
• Running PreToolUse hook: name for demo pre tool use hook
PreToolUse hook (completed)
warning: wizard-tower PreToolUse demo inspected Bash: echo "first parallel echo"
PreToolUse hook (blocked)
warning: wizard-tower PreToolUse demo blocked a Bash command on purpose.
feedback: PreToolUse demo blocked the command. Remove [block-pre-tool-use] to continue.
PreToolUse hook (completed)
warning: wizard-tower PreToolUse demo inspected Bash: echo "third parallel echo"
• Ran echo "first parallel echo"
└ first parallel echo
• Ran echo "third parallel echo"
└ third parallel echo
• Three little waves went out in parallel.
1. printed first parallel echo
2. was blocked before execution because it contained the exact test string [block-pre-tool-use]
3. printed third parallel echo
There was also an unrelated macOS defaults warning around the successful commands, but the echoes
themselves worked fine. If you want, I can rerun the second one with a slightly modified string so
it passes cleanly.
```
- this allows blocking the user's prompts from executing, and also
prevents them from entering history
- handles the edge case where you can both prevent the user's prompt AND
add n amount of additionalContexts
- refactors some old code into common.rs where hooks overlap
functionality
- refactors additionalContext being previously added to user messages,
instead we use developer messages for them
- handles queued messages correctly
Sample hook for testing - if you write "[block-user-submit]" this hook
will stop the thread:
example run
```
› sup
• Running UserPromptSubmit hook: reading the observatory notes
UserPromptSubmit hook (completed)
warning: wizard-tower UserPromptSubmit demo inspected: sup
hook context: Wizard Tower UserPromptSubmit demo fired. For this reply only, include the exact
phrase 'observatory lanterns lit' exactly once near the end.
• Just riding the cosmic wave and ready to help, my friend. What are we building today? observatory
lanterns lit
› and [block-user-submit]
• Running UserPromptSubmit hook: reading the observatory notes
UserPromptSubmit hook (stopped)
warning: wizard-tower UserPromptSubmit demo blocked the prompt on purpose.
stop: Wizard Tower demo block: remove [block-user-submit] to continue.
```
.codex/config.toml
```
[features]
codex_hooks = true
```
.codex/hooks.json
```
{
"hooks": {
"UserPromptSubmit": [
{
"hooks": [
{
"type": "command",
"command": "/usr/bin/python3 .codex/hooks/user_prompt_submit_demo.py",
"timeoutSec": 10,
"statusMessage": "reading the observatory notes"
}
]
}
]
}
}
```
.codex/hooks/user_prompt_submit_demo.py
```
#!/usr/bin/env python3
import json
import sys
from pathlib import Path
def prompt_from_payload(payload: dict) -> str:
prompt = payload.get("prompt")
if isinstance(prompt, str) and prompt.strip():
return prompt.strip()
event = payload.get("event")
if isinstance(event, dict):
user_prompt = event.get("user_prompt")
if isinstance(user_prompt, str):
return user_prompt.strip()
return ""
def main() -> int:
payload = json.load(sys.stdin)
prompt = prompt_from_payload(payload)
cwd = Path(payload.get("cwd", ".")).name or "wizard-tower"
if "[block-user-submit]" in prompt:
print(
json.dumps(
{
"systemMessage": (
f"{cwd} UserPromptSubmit demo blocked the prompt on purpose."
),
"decision": "block",
"reason": (
"Wizard Tower demo block: remove [block-user-submit] to continue."
),
}
)
)
return 0
prompt_preview = prompt or "(empty prompt)"
if len(prompt_preview) > 80:
prompt_preview = f"{prompt_preview[:77]}..."
print(
json.dumps(
{
"systemMessage": (
f"{cwd} UserPromptSubmit demo inspected: {prompt_preview}"
),
"hookSpecificOutput": {
"hookEventName": "UserPromptSubmit",
"additionalContext": (
"Wizard Tower UserPromptSubmit demo fired. "
"For this reply only, include the exact phrase "
"'observatory lanterns lit' exactly once near the end."
),
},
}
)
)
return 0
if __name__ == "__main__":
raise SystemExit(main())
```
## Why
Once the repo-local lint exists, `codex-rs` needs to follow the
checked-in convention and CI needs to keep it from drifting. This commit
applies the fallback `/*param*/` style consistently across existing
positional literal call sites without changing those APIs.
The longer-term preference is still to avoid APIs that require comments
by choosing clearer parameter types and call shapes. This PR is
intentionally the mechanical follow-through for the places where the
existing signatures stay in place.
After rebasing onto newer `main`, the rollout also had to cover newly
introduced `tui_app_server` call sites. That made it clear the first cut
of the CI job was too expensive for the common path: it was spending
almost as much time installing `cargo-dylint` and re-testing the lint
crate as a representative test job spends running product tests. The CI
update keeps the full workspace enforcement but trims that extra
overhead from ordinary `codex-rs` PRs.
## What changed
- keep a dedicated `argument_comment_lint` job in `rust-ci`
- mechanically annotate remaining opaque positional literals across
`codex-rs` with exact `/*param*/` comments, including the rebased
`tui_app_server` call sites that now fall under the lint
- keep the checked-in style aligned with the lint policy by using
`/*param*/` and leaving string and char literals uncommented
- cache `cargo-dylint`, `dylint-link`, and the relevant Cargo
registry/git metadata in the lint job
- split changed-path detection so the lint crate's own `cargo test` step
runs only when `tools/argument-comment-lint/*` or `rust-ci.yml` changes
- continue to run the repo wrapper over the `codex-rs` workspace, so
product-code enforcement is unchanged
Most of the code changes in this commit are intentionally mechanical
comment rewrites or insertions driven by the lint itself.
## Verification
- `./tools/argument-comment-lint/run.sh --workspace`
- `cargo test -p codex-tui-app-server -p codex-tui`
- parsed `.github/workflows/rust-ci.yml` locally with PyYAML
---
* -> #14652
* #14651
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)
