[BUG CLIENT]: Tool choice required can hang indefinitely for some models

[louis-sanna-dev]

This issue is to track a separate problem from the previously discussed client/event-loop behavior.

Separately, the server-side request appears to hang indefinitely for some models when using tool calling with tool_choice="required".

Repro:

await client.chat.complete_async(
    model="mistral-small-latest",  # or "mistral-vibe-cli-fast"
    messages=[{"role": "user", "content": "Say hello."}],
    tools=[{"type": "function", "function": {"name": "f", "parameters": {"type": "object"}}}],
    tool_choice="required",
    timeout_ms=120000,
)

Observed behavior:

• The request does not complete.
• With timeout_ms=120000, the client eventually raises ReadTimeout after 120 seconds.
• The server never seems to return a response for this payload.

Expected behavior:

• Either a normal tool-call response is returned quickly, or the API rejects the request explicitly.
• It should not hang indefinitely until the client-side timeout is reached.

Notes:

• Affected models observed so far: mistral-small-latest.