ChatCompletionStreamResponseDelta omits streamed audio data

Source reports

• https://github.com/openai/openai-python/issues/2507

Current specification gap

Affected surface: POST /chat/completions stream; ChatCompletionStreamResponseDelta.audio.

The source reports audio fields returned by streaming gpt-4o-audio-preview and gpt-4o-mini-audio-preview calls, while the SDK and API reference omit the field. The current public delta component still has no audio property.

Specification reviewed at b61ced9.

Minimal shape

{
  "audio": {
    "expires_at": 1234567890
  }
}

This is a sanitized illustration of the reported shape, not a new live API capture.

Expected reconciliation

Describe the streamed audio delta shape and per-chunk optional fields, including the final expiry update, then regenerate SDK types.

Verification scope

Reviewed the source reports, relevant comments, and current published schema. No new live API request was made. This mirrors the specification gap and preserves the original reproduction; it does not claim that a fix has shipped.

Start with openapi.yaml at the reviewed ChatCompletionStreamResponseDelta definition around line 31939, then compare it with the linked source report and comments. Document the streamed audio delta shape and its optional per-chunk fields, including the final expiry update, and regenerate the SDK types; done means the public schema includes the audio property.