curl --location '/v1/messages' \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '{
    "model": "claude-fable-5-1",
    "max_tokens": 1024,
    "system": [
        {
            "type": "text",
            "text": "Hi",
            "cache_control": {
                "type": "ephemeral"
            }
        }
    ],
    "messages": [
        {
            "role": "user",
            "content": "请确认收到文档，并简单回复：已收到。"
        }
    ]
}'