GitHub Release: openai/codex vpython-v0.154.0 (10.09.2026)

$ git clone https://github.com/openai/codex.git Clone

Install with pip install --upgrade openai-codex==0.154.0 (Python 3.10 or later). This release includes the matching openai-codex-cli-bin==0.154.0 runtime.

• Add max and ultra reasoning-effort values.


• Add include_turns on resume/fork, turn_service_tier for one newly started turn, and source metadata. History selection changes the returned response, not model context. Existing defaults are preserved when these options are omitted. , #44400

Check these migrations when upgrading:

• HookMetadata wraps its handler in .root. Replace accesses such as hook.command with hook.root.command, checking hook.root.handler_type before reading handler-specific fields.


• Some previously unknown notifications now have typed payloads. Read named fields instead of .params; unknown or invalid payloads still use UnknownNotification.


• Manually constructed or late-joining turn handles receive events from their attachment point. Earlier output is not replayed, so collected results can be partial; attaching after completion can raise TransportClosedError. Use thread.read(include_turns=True) for saved history. Handles returned directly by thread.turn(...) retain events from when their request is sent.

Custom codex_bin overrides require CLI 0.151.0 or newer for ExternalMessage and the new history/per-turn options.