## Why
Private IP destinations always bypassed inherited upstream proxies, preventing their use for private networks reachable through an upstream VPN proxy.
## What changed
- Add `codex exec-server --proxy-private-ips-via-upstream`, also configurable with `CODEX_EXEC_SERVER_PROXY_PRIVATE_IPS_VIA_UPSTREAM=true`. The setting defaults to disabled.
- Allow permitted RFC 1918, carrier-grade NAT, and IPv6 unique-local destinations to use an applicable upstream proxy. Loopback and link-local destinations retain direct routing, and destination access policy still applies.
- Keep connections direct when no valid upstream proxy applies or `allow_upstream_proxy=false`. Errors after selecting an upstream proxy do not trigger a direct retry.
- Rename `ExecServerRuntimePaths` to `ExecServerRuntimeOptions` and carry the routing setting from executor startup into the managed network proxy.
## Testing
Add routing coverage for private address ranges, special-use addresses, and public targets with the option enabled and disabled. Verify that HTTP and CONNECT requests still enforce destination allowlists and denylists, and update the CLI help snapshot.
GitOrigin-RevId: b7c9cc7da0e0f545694a6521b74c9b36b7b92769
## Why
Linux pipe launches need session, parent-death signal, and descriptor setup. Move this work into a fresh, single-threaded executable image to avoid forking the app-server for child setup.
## What changed
- Register an early setup helper and launch it through `posix_spawn` for Linux pipe processes.
- Start the helper with an empty environment, then transfer the target environment over a control socket so loader settings cannot interfere with helper startup.
- Await target execution asynchronously, propagate setup and execution errors, and kill incomplete launches on cancellation.
- Preserve direct spawning as a fallback when the helper is unavailable or fails before target execution.
## Testing
Add coverage for launch semantics, avoiding fork, loader environment isolation, early argument dispatch, closed standard descriptors, and fallback under bootstrap failure or descriptor pressure. Add an app-server regression test that reuses a process handle after an execution failure.
GitOrigin-RevId: 079c673f0f22ebd531f8c57e5338095cc98acfdc
## Why
Delegated HTTP requests need to honor the same outbound proxy policy as the
Codex process that starts the exec server.
## What changed
- Pass the configured `HttpClientFactory` through local and remote exec-server
startup and use route-aware client pools for delegated HTTP and local MCP
requests.
- Preserve per-request timeouts and follow-or-stop redirect behavior while
keeping request URLs and sensitive response headers out of diagnostics.
## Testing
- Cover configured system-proxy routing across the exec-server transport.
- Cover both redirect policies and verify that success and failure logs do not
expose request or response secrets.
GitOrigin-RevId: 4af6aec1d265c4db62dfcb6e1fb076fb31736137
## Why
Sandbox wrappers replaced the process launch command and did not carry an
`ExecParams.arg0` override through to the inner process.
## What changed
- Route sandboxed Unix launches with a custom `arg0` through a helper mode that
re-execs the requested program with the override.
- Expose the helper executable to the filesystem sandbox and dispatch its mode
from Codex and exec-server test binaries.
## Testing
Add coverage for the prepared sandbox command and an end-to-end remote process
that verifies both the custom `arg0` and filesystem restrictions.
GitOrigin-RevId: c9f8eef3906d184e670184c2eeed250d5895a9ca
## Why
Macrobenchmarks benefit from having a way to exercise remote-executor
latency without depending on Docker.
This is a very minimal first cut, if we find that simulating network
conditions is useful we can always expand this scope or switch to a more
robust network shaping approach.
## What
- add a package-local exec-server binary for Cargo and Bazel test
fixtures
- add a host-local WebSocket exec-server fixture and fixed-delay
interposer
- let TestAppServer route its auto environment through that delayed
WebSocket transport
- cover the delayed thread/start path through the public app-server API
## Stack
1. [#31425 test: add TestAppServer
builder](https://github.com/openai/codex/pull/31425)
2. [#31427 test: add delayed exec-server
transport](https://github.com/openai/codex/pull/31427)
3. [#31295 bench: add cold skill load
macrobenchmark](https://github.com/openai/codex/pull/31295)
4. [#31428 bench: add e2e benchmark
entrypoints](https://github.com/openai/codex/pull/31428)
5. [#31429 ci: smoke Bazel e2e
benchmarks](https://github.com/openai/codex/pull/31429)
## What changed
- This PR changes only the flaky test setup for
`turn_start_notify_payload_includes_initialize_client_name`.
- Instead of shelling out to `python3` to write the notify payload, the
test uses the first-party `codex-app-server-test-notify-capture` helper.
- The helper writes `notify.json` atomically and the test waits for the
file to exist before reading it.
## Why this fixes the flake
- The old test depended on an external Python interpreter being present
and behaving consistently on every CI runner.
- It also raced the file write: the test could observe the path before
the payload had been fully written, which produced partial reads and
intermittent assertion failures.
- Moving the write into a repo-owned helper removes the external
dependency, and atomic write-plus-wait makes the handoff deterministic.
## Scope
- Test-only change.
- production logic plus tests; cancel running tasks before clearing
pending turn state
- suppress follow-up model requests after cancellation and assert on
stabilized request counts instead of fixed sleeps
open-matt