fix(_utils/_transform): propagate __api_exclude__ in _async_transform_recursive

[rmotgi1227]

Summary

The sync _transform_recursive path (line 221 of _utils/_transform.py) correctly passes exclude=getattr(data, "__api_exclude__", None) to model_dump() when it encounters a pydantic BaseModel value. The async counterpart _async_transform_recursive (line 387) was missing this argument.

Bug

# sync — correct
if isinstance(data, pydantic.BaseModel):
    return model_dump(data, exclude_unset=True, mode="json", exclude=getattr(data, "__api_exclude__", None))

# async — missing exclude= kwarg (before this fix)
if isinstance(data, pydantic.BaseModel):
    return model_dump(data, exclude_unset=True, mode="json")

Impact

ParsedResponse (in openai/types/responses/parsed_response.py) declares:

__api_exclude__ = {"parsed_arguments"}

This is specifically to prevent the client-side computed parsed_arguments field from being sent back to the API server in multi-turn conversations. With the async client that exclusion had no effect: parsed_arguments leaked into every request body that included a ParsedResponse in the message history.

Fix

One-line change — add the missing exclude kwarg to match the sync path:

return model_dump(data, exclude_unset=True, mode="json", exclude=getattr(data, "__api_exclude__", None))

Tests

Added tests/test_async_transform_api_exclude.py with three tests (no live API calls):

1. test_async_transform_excludes_api_excluded_fields — asserts __api_exclude__ fields are absent from the async output (this test fails before the fix, passes after)
2. test_sync_transform_excludes_api_excluded_fields — sanity-check that the sync path behaves the same
3. test_async_transform_pydantic_model_without_api_exclude — models without __api_exclude__ are unaffected

Run with PYTHONPATH=src pytest tests/test_async_transform_api_exclude.py.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: b762fc6492

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".

[chatgpt-codex-connector]

Remove the unused asyncio import

When the repo's lint/typecheck checks include this new test file, this import makes ruff check . fail with F401 (and import ordering I001), so the change cannot pass CI until the unused import is removed.

Useful? React with 👍 / 👎.