Add Python app-server SDK

Co-authored-by: Codex <noreply@openai.com>

sdk/python/README.md

@@ -0,0 +1,95 @@
+# Codex App Server Python SDK (Experimental)
+
+Experimental Python SDK for `codex app-server` JSON-RPC v2 over stdio, with a small default surface optimized for real scripts and apps.
+
+The generated wire-model layer is currently sourced from the bundled v2 schema and exposed as Pydantic models with snake_case Python fields that serialize back to the app-server’s camelCase wire format.
+
+## Install
+
+```bash
+cd sdk/python
+python -m pip install -e .
+```
+
+Published SDK builds pin an exact `codex-cli-bin` runtime dependency. For local
+repo development, pass `AppServerConfig(codex_bin=...)` to point at a local
+build explicitly.
+
+## Quickstart
+
+```python
+from codex_app_server import Codex, TextInput
+
+with Codex() as codex:
+    thread = codex.thread_start(model="gpt-5")
+    result = thread.turn(TextInput("Say hello in one sentence.")).run()
+    print(result.text)
+```
+
+## Docs map
+
+- Golden path tutorial: `docs/getting-started.md`
+- API reference (signatures + behavior): `docs/api-reference.md`
+- Common decisions and pitfalls: `docs/faq.md`
+- Runnable examples index: `examples/README.md`
+- Jupyter walkthrough notebook: `notebooks/sdk_walkthrough.ipynb`
+
+## Examples
+
+Start here:
+
+```bash
+cd sdk/python
+python examples/01_quickstart_constructor/sync.py
+python examples/01_quickstart_constructor/async.py
+```
+
+## Runtime packaging
+
+The repo no longer checks `codex` binaries into `sdk/python`.
+
+Published SDK builds are pinned to an exact `codex-cli-bin` package version,
+and that runtime package carries the platform-specific binary for the target
+wheel.
+
+For local repo development, the checked-in `sdk/python-runtime` package is only
+a template for staged release artifacts. Editable installs should use an
+explicit `codex_bin` override instead.
+
+## Maintainer workflow
+
+```bash
+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
+```
+
+This supports the CI release flow:
+
+- run `generate-types` before packaging
+- stage `codex-app-server-sdk` once with an exact `codex-cli-bin==...` dependency
+- stage `codex-cli-bin` on each supported platform runner with the same pinned runtime version
+- build and publish `codex-cli-bin` as platform wheels only; do not publish an sdist
+
+## Compatibility and versioning
+
+- Package: `codex-app-server-sdk`
+- Runtime package: `codex-cli-bin`
+- Current SDK version in this repo: `0.2.0`
+- Python: `>=3.10`
+- Target protocol: Codex `app-server` JSON-RPC v2
+- Recommendation: keep SDK and `codex` CLI reasonably up to date together
+
+## Notes
+
+- `Codex()` is eager and performs startup + `initialize` in the constructor.
+- Use context managers (`with Codex() as codex:`) to ensure shutdown.
+- For transient overload, use `codex_app_server.retry.retry_on_overload`.