event: message_start
data: {"type": "message_start", "message": {"id": "msg_thinking_01", "type": "message", "role": "assistant", "content": [], "model": "claude-sonnet-4-5", "stop_reason": null, "stop_sequence": null, "usage": {"input_tokens": 42, "output_tokens": 1, "thinking_tokens": 318}}}

event: content_block_start
data: {"type": "content_block_start", "index": 0, "content_block": {"type": "thinking", "thinking": ""}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "Let me think about this carefully..."}}

event: content_block_stop
data: {"type": "content_block_stop", "index": 0}

event: content_block_start
data: {"type": "content_block_start", "index": 1, "content_block": {"type": "text", "text": ""}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 1, "delta": {"type": "text_delta", "text": "The answer is 42."}}

event: content_block_stop
data: {"type": "content_block_stop", "index": 1}

event: message_delta
data: {"type": "message_delta", "delta": {"stop_reason": "end_turn", "stop_sequence": null}, "usage": {"output_tokens": 7}}

event: message_stop
data: {"type": "message_stop"}

