## Summary
- Record bounded connection, request, and process lifecycle metrics.
- Report active gauges from callbacks on every collection, including
delta exports.
- Serialize active-count updates so concurrent starts and finishes
cannot publish stale values.
- Serialize process exit, explicit termination, and shutdown through the
process registry so exactly one completion result wins.
- Keep the implementation small with single-owner RAII guards and one
real OTLP/HTTP integration test using the existing `wiremock`
dependency.
## Root cause
Process exit and session shutdown previously used cloned completion
state. That avoided duplicate emission, but it duplicated lifecycle
ownership and made the ordering harder to reason about. The process
registry mutex already defines the lifecycle ordering, so the final
implementation stores the metric guard and termination flag directly on
the process entry. Whichever path claims the entry first owns the
completion result.
Production metric export uses delta temporality. Event-only synchronous
gauge recordings disappear after the next collection when no count
changes, so active counts now use observable callbacks that report
current state on every collection.
The cleanup also removes the constant `result="accepted"` connection
tag, redundant route and response assertions, a custom HTTP collector,
and fallback initialization machinery that did not add behavior.
## Stack
Review and land this stack in order:
1. #27466 — trace exec-server JSON-RPC requests
2. #27467 — record bounded connection, request, and process lifecycle
metrics **(this PR)**
3. #27470 — observe remote registration and Noise rendezvous lifecycle
## Validation
- `just test -p codex-exec-server --lib` (158 passed)
- `just test -p codex-cli --test exec_server` (3 passed)
- `just test -p codex-otel
observable_gauge_is_collected_on_every_delta_snapshot` (1 passed)
- `CARGO_BUILD_JOBS=1 just fix -p codex-otel -p codex-exec-server`
- `just fmt`
- `git diff --check`
## Summary
- reduce public module visibility across Rust crates, preferring private
or crate-private modules with explicit crate-root public exports
- update external call sites and tests to use the intended public crate
APIs instead of reaching through module trees
- add the module visibility guideline to AGENTS.md
## Validation
- `cargo check --workspace --all-targets --message-format=short` passed
before the final fix/format pass
- `just fix` completed successfully
- `just fmt` completed successfully
- `git diff --check` passed
## 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.
## Summary
This is a purely mechanical refactor of `OtelManager` ->
`SessionTelemetry` to better convey what the struct is doing. No
behavior change.
## Why
`OtelManager` ended up sounding much broader than what this type
actually does. It doesn't manage OTEL globally; it's the session-scoped
telemetry surface for emitting log/trace events and recording metrics
with consistent session metadata (`app_version`, `model`, `slug`,
`originator`, etc.).
`SessionTelemetry` is a more accurate name, and updating the call sites
makes that boundary a lot easier to follow.
## Validation
- `just fmt`
- `cargo test -p codex-otel`
- `cargo test -p codex-core`
So that the rest of the codebase (like TUI) don't need to be concerned
whether ChatGPT auth was handled by Codex itself or passed in via
app-server's external auth mode.