event: response.created
data: {"type":"response.created","response":{"id":"resp_text_1","status":"in_progress"}}

event: response.output_text.delta
data: {"type":"response.output_text.delta","item_id":"msg_1","delta":"Hello"}

event: response.output_text.delta
data: {"type":"response.output_text.delta","item_id":"msg_1","delta":" from Responses"}

event: response.completed
data: {"type":"response.completed","response":{"id":"resp_text_1","status":"completed","usage":{"input_tokens":20,"output_tokens":5,"input_tokens_details":{"cached_tokens":8}}}}

