event: message_start
data: {"type": "message_start", "message": {"id": "msg_01CacheTestStream", "type": "message", "role": "assistant", "content": [], "model": "claude-sonnet-4-5", "stop_reason": null, "stop_sequence": null, "usage": {"input_tokens": 21, "output_tokens": 1, "cache_creation_input_tokens": 2048, "cache_read_input_tokens": 512}}}

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

event: ping
data: {"type": "ping"}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "text_delta", "text": "ok"}}

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

event: message_delta
data: {"type": "message_delta", "delta": {"stop_reason": "end_turn", "stop_sequence": null}, "usage": {"output_tokens": 4}}

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

