Files
codex/sdk/python/docs/faq.md
Owen Lin 9b3332e62f fix(python-sdk): stop checking in codex binaries; stage pinned runtim… (#14232)
…e package

## Summary

This changes the Python SDK packaging model so we no longer commit
`codex`
binaries into `sdk/python`.

Instead, published SDK builds now depend on a separate `codex-cli-bin`
runtime
package that carries the platform-specific `codex` binary. The SDK and
runtime
can be staged together with an exact version pin, so the published
Python SDK
still resolves to a Codex version we know is compatible.

The SDK now resolves `codex` in this order:

- `AppServerConfig.codex_bin` if explicitly set
- installed `codex-cli-bin` runtime package

There is no `PATH` fallback anymore. Published installs either use the
pinned
runtime or fail loudly, and local development uses an explicit
`codex_bin`
override when working from the repo.

## What changed

- removed checked-in binaries from `sdk/python/src/codex_app_server/bin`
- changed `AppServerClient` to resolve `codex` from:
  - explicit `AppServerConfig.codex_bin`
  - installed `codex-cli-bin`
- kept `AppServerConfig.codex_bin` override support for local/dev use
- added a new `sdk/python-runtime` package template for the pinned
runtime
- updated `scripts/update_sdk_artifacts.py` to stage releasable
SDK/runtime
  packages instead of downloading binaries into the repo
- made `codex-cli-bin` build as a platform-specific wheel
- made `codex-cli-bin` wheel-only by rejecting `sdist` builds
- updated docs/tests to match the new packaging flow and explicit
local-dev
  contract

## Why

Checking in six platform binaries made the repo much heavier and tied
normal
source changes to release artifacts.

This keeps the compatibility guarantees we want, but moves them into
packaging:

- the published SDK can depend on an exact `codex-cli-bin==...`
- the runtime package carries the platform-specific binary
- users still get a pinned runtime
- the repo no longer needs to store those binaries

It also makes the runtime contract stricter and more predictable:

- published installs never silently fall back to an arbitrary `codex` on
`PATH`
- local development remains supported through explicit `codex_bin`
- `codex-cli-bin` is distributed as platform wheels only, which avoids
unsafe
source-distribution installs for a package that embeds a prebuilt binary

## Validation

- ran targeted Python SDK tests:
- `python3 -m pytest
sdk/python/tests/test_artifact_workflow_and_binaries.py
sdk/python/tests/test_client_rpc_methods.py
sdk/python/tests/test_contract_generation.py`
- exercised the staging flow with a local dummy binary to verify
SDK/runtime
  staging end to end
- verified the staged runtime package builds a platform-specific wheel
(`Root-Is-Purelib: false`) rather than a universal `py3-none-any` wheel
- added test coverage for the explicit-only runtime resolution model
- added test coverage that `codex-cli-bin` rejects `sdist` builds

---------

Co-authored-by: sdcoffey <stevendcoffey@gmail.com>
2026-03-10 13:53:08 -07:00

2.7 KiB

FAQ

Thread vs turn

  • A Thread is conversation state.
  • A Turn is one model execution inside that thread.
  • Multi-turn chat means multiple turns on the same Thread.

run() vs stream()

  • Turn.run() is the easiest path. It consumes events until completion and returns TurnResult.
  • Turn.stream() yields raw notifications (Notification) so you can react event-by-event.

Choose run() for most apps. Choose stream() for progress UIs, custom timeout logic, or custom parsing.

Sync vs async clients

  • Codex is the minimal sync SDK and best default.
  • AsyncAppServerClient wraps the sync transport with asyncio.to_thread(...) for async-friendly call sites.

If your app is not already async, stay with Codex.

thread(...) vs thread_resume(...)

  • codex.thread(thread_id) only binds a local helper to an existing thread ID.
  • codex.thread_resume(thread_id, ...) performs a thread/resume RPC and can apply overrides (model, instructions, sandbox, etc.).

Use thread(...) for simple continuation. Use thread_resume(...) when you need explicit resume semantics or override fields.

Why does constructor fail?

Codex() is eager: it starts transport and calls initialize in __init__.

Common causes:

  • published runtime package (codex-cli-bin) is not installed
  • local codex_bin override points to a missing file
  • local auth/session is missing
  • incompatible/old app-server

Maintainers stage releases by building the SDK once and the runtime once per platform with the same pinned runtime version. Publish codex-cli-bin as platform wheels only; do not publish an sdist:

cd sdk/python
python scripts/update_sdk_artifacts.py generate-types
python scripts/update_sdk_artifacts.py \
  stage-sdk \
  /tmp/codex-python-release/codex-app-server-sdk \
  --runtime-version 1.2.3
python scripts/update_sdk_artifacts.py \
  stage-runtime \
  /tmp/codex-python-release/codex-cli-bin \
  /path/to/codex \
  --runtime-version 1.2.3

Why does a turn "hang"?

A turn is complete only when turn/completed arrives for that turn ID.

  • run() waits for this automatically.
  • With stream(), make sure you keep consuming notifications until completion.

How do I retry safely?

Use retry_on_overload(...) for transient overload failures (ServerBusyError).

Do not blindly retry all errors. For InvalidParamsError or MethodNotFoundError, fix inputs/version compatibility instead.

Common pitfalls

  • Starting a new thread for every prompt when you wanted continuity.
  • Forgetting to close() (or not using with Codex() as codex:).
  • Ignoring TurnResult.status and TurnResult.error.
  • Mixing SDK input classes with raw dicts incorrectly in minimal API paths.