{
  "max_tokens": 1024,
  "tools": [...],
  "thinking_level": "high"
}

{
  "role": "user",
  "content_items": [{
    "type": "text.done",
    "text": "Who am I"
  }]
}

MMSP

Model Message Stream Protocol

async for event in client.streaming_response_stateful

{
  "event_type": "stop",
  "content_items": [],
  "usage_metadata": {
    "prompt_tokens": 12,
    "response_tokens": 8
  },
  "finish_reason": "stop"
}