Enhance pty utils:
* Support closing stdin
* Separate stderr and stdout streams to allow consumers differentiate them
* Provide compatibility helper to merge both streams back into combined one
* Support specifying terminal size for pty, including on-demand resizes while process is already running
* Support terminating the process while still consuming its outputs
## Problem
Browser login failures historically leave support with an incomplete
picture. HARs can show that the browser completed OAuth and reached the
localhost callback, but they do not explain why the native client failed
on the final `/oauth/token` exchange. Direct `codex login` also relied
mostly on terminal stderr and the browser error page, so even when the
login crate emitted better sign-in diagnostics through TUI or app-server
flows, the one-shot CLI path still did not leave behind an easy artifact
to collect.
## Mental model
This implementation treats the browser page, the returned `io::Error`,
and the normal structured log as separate surfaces with different safety
requirements. The browser page and returned error preserve the detail
that operators need to diagnose failures. The structured log stays
narrower: it records reviewed lifecycle events, parsed safe fields, and
redacted transport errors without becoming a sink for secrets or
arbitrary backend bodies.
Direct `codex login` now adds a fourth support surface: a small
file-backed log at `codex-login.log` under the configured `log_dir`.
That artifact carries the same login-target events as the other
entrypoints without changing the existing stderr/browser UX.
## Non-goals
This does not add auth logging to normal runtime requests, and it does
not try to infer precise transport root causes from brittle string
matching. The scope remains the browser-login callback flow in the
`login` crate plus a direct-CLI wrapper that persists those events to
disk.
This also does not try to reuse the TUI logging stack wholesale. The TUI
path initializes feedback, OpenTelemetry, and other session-oriented
layers that are useful for an interactive app but unnecessary for a
one-shot login command.
## Tradeoffs
The implementation favors fidelity for caller-visible errors and
restraint for persistent logs. Parsed JSON token-endpoint errors are
logged safely by field. Non-JSON token-endpoint bodies remain available
to the returned error so CLI and browser surfaces still show backend
detail. Transport errors keep their real `reqwest` message, but attached
URLs are surgically redacted. Custom issuer URLs are sanitized before
logging.
On the CLI side, the code intentionally duplicates a narrow slice of the
TUI file-logging setup instead of sharing the full initializer. That
keeps `codex login` easy to reason about and avoids coupling it to
interactive-session layers that the command does not need.
## Architecture
The core auth behavior lives in `codex-rs/login/src/server.rs`. The
callback path now logs callback receipt, callback validation,
token-exchange start, token-exchange success, token-endpoint non-2xx
responses, and transport failures. App-server consumers still use this
same login-server path via `run_login_server(...)`, so the same
instrumentation benefits TUI, Electron, and VS Code extension flows.
The direct CLI path in `codex-rs/cli/src/login.rs` now installs a small
file-backed tracing layer for login commands only. That writes
`codex-login.log` under `log_dir` with login-specific targets such as
`codex_cli::login` and `codex_login::server`.
## Observability
The main signals come from the `login` crate target and are
intentionally scoped to sign-in. Structured logs include redacted issuer
URLs, redacted transport errors, HTTP status, and parsed token-endpoint
fields when available. The callback-layer log intentionally avoids
`%err` on token-endpoint failures so arbitrary backend bodies do not get
copied into the normal log file.
Direct `codex login` now leaves a durable artifact for both failure and
success cases. Example output from the new file-backed CLI path:
Failing callback:
```text
2026-03-06T22:08:54.143612Z INFO codex_cli::login: starting browser login flow
2026-03-06T22:09:03.431699Z INFO codex_login::server: received login callback path=/auth/callback has_code=false has_state=true has_error=true state_valid=true
2026-03-06T22:09:03.431745Z WARN codex_login::server: oauth callback returned error error_code="access_denied" has_error_description=true
```
Succeeded callback and token exchange:
```text
2026-03-06T22:09:14.065559Z INFO codex_cli::login: starting browser login flow
2026-03-06T22:09:36.431678Z INFO codex_login::server: received login callback path=/auth/callback has_code=true has_state=true has_error=false state_valid=true
2026-03-06T22:09:36.436977Z INFO codex_login::server: starting oauth token exchange issuer=https://auth.openai.com/ redirect_uri=http://localhost:1455/auth/callback
2026-03-06T22:09:36.685438Z INFO codex_login::server: oauth token exchange succeeded status=200 OK
```
## Tests
- `cargo test -p codex-login`
- `cargo clippy -p codex-login --tests -- -D warnings`
- `cargo test -p codex-cli`
- `just bazel-lock-update`
- `just bazel-lock-check`
- manual direct `codex login` smoke tests for both a failing callback
and a successful browser login
---------
Co-authored-by: Codex <noreply@openai.com>
## Summary
This is a structural cleanup of `codex-otel` to make the ownership
boundaries a lot clearer.
For example, previously it was quite confusing that `OtelManager` which
emits log + trace event telemetry lived under
`codex-rs/otel/src/traces/`. Also, there were two places that defined
methods on OtelManager via `impl OtelManager` (`lib.rs` and
`otel_manager.rs`).
What changed:
- move the `OtelProvider` implementation into `src/provider.rs`
- move `OtelManager` and session-scoped event emission into
`src/events/otel_manager.rs`
- collapse the shared log/trace event helpers into
`src/events/shared.rs`
- pull target classification into `src/targets.rs`
- move `traceparent_context_from_env()` into `src/trace_context.rs`
- keep `src/otel_provider.rs` as a compatibility shim for existing
imports
- update the `codex-otel` README to reflect the new layout
## Why
`lib.rs` and `otel_provider.rs` were doing too many different jobs at
once: provider setup, export routing, trace-context helpers, and session
event emission all lived together.
This refactor separates those concerns without trying to change the
behavior of the crate. The goal is to make future OTEL work easier to
reason about and easier to review.
## Notes
- no intended behavior change
- `OtelManager` remains the session-scoped event emitter in this PR
- the `otel_provider` shim keeps downstream churn low while the
internals move around
## Validation
- `just fmt`
- `cargo test -p codex-otel`
- `just fix -p codex-otel`
Michael Bolin