## 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.
**Motivation**
The `originator` header is important for codex-backend’s Responses API
proxy because it identifies the real end client (codex cli, codex vscode
extension, codex exec, future IDEs) and is used to categorize requests
by client for our enterprise compliance API.
Today the `originator` header is set by either:
- the `CODEX_INTERNAL_ORIGINATOR_OVERRIDE` env var (our VSCode extension
does this)
- calling `set_default_originator()` which sets a global immutable
singleton (`codex exec` does this)
For `codex app-server`, we want the `initialize` JSON-RPC request to set
that header because it is a natural place to do so. Example:
```json
{
"method": "initialize",
"id": 0,
"params": {
"clientInfo": {
"name": "codex_vscode",
"title": "Codex VS Code Extension",
"version": "0.1.0"
}
}
}
```
and when app-server receives that request, it can call
`set_default_originator()`. This is a much more natural interface than
asking third party developers to set an env var.
One hiccup is that `originator()` reads the global singleton and locks
in the value, preventing a later `set_default_originator()` call from
setting it. This would be fine but is brittle, since any codepath that
calls `originator()` before app-server can process an `initialize`
JSON-RPC call would prevent app-server from setting it. This was
actually the case with OTEL initialization which runs on boot, but I
also saw this behavior in certain tests.
Instead, what we now do is:
- [unchanged] If `CODEX_INTERNAL_ORIGINATOR_OVERRIDE` env var is set,
`originator()` would return that value and `set_default_originator()`
with some other value does NOT override it.
- [new] If no env var is set, `originator()` would return the default
value which is `codex_cli_rs` UNTIL `set_default_originator()` is called
once, in which case it is set to the new value and becomes immutable.
Later calls to `set_default_originator()` returns
`SetOriginatorError::AlreadyInitialized`.
**Other notes**
- I updated `codex_core::otel_init::build_provider` to accepts a service
name override, and app-server sends a hardcoded `codex_app_server`
service name to distinguish it from `codex_cli_rs` used by default (e.g.
TUI).
**Next steps**
- Update VSCE to set the proper value for `clientInfo.name` on
`initialize` and drop the `CODEX_INTERNAL_ORIGINATOR_OVERRIDE` env var.
- Delete support for `CODEX_INTERNAL_ORIGINATOR_OVERRIDE` in codex-rs.
