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• ✅Have you read the docs?
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Describe the bug

When using an OpenAI-API compatible provider , the streamed response may include a final chunk with choices: []. The convertChatCompletionsStreamToResponses function in openaiChatCompletionsStreaming.ts assumes chunk.choices[0] exists, and throws:

TypeError: Cannot read properties of undefined (reading 'delta')

This is due to this line:

if (!chunk.choices?.[0]?.delta) continue;

This line assumes chunk.choices is non-empty, but according to the OpenAI Chat Completions Streaming API documentation:

choices: Can also be empty for the last chunk if you set stream_options: {"include_usage": true}.

So choices: [] seems a valid case, and should be handled gracefully by the SDK for compatibility with OpenAI-compatible providers.

Debug information

• Agents SDK version: (e.g. v0.0.7)
• Runtime environment (e.g. Node.js 22.11.0)