curl --request POST \
  --url https://api.ttapi.io/gemini/chat/completions \
  --header 'Content-Type: application/json' \
  --header 'TT-API-KEY: <api-key>' \
  --data '
{
  "messages": [
    {
      "role": "system",
      "content": "You are a helpful assistant."
    },
    {
      "role": "user",
      "content": "Hello!"
    }
  ],
  "model": "<string>",
  "...": "<unknown>"
}
'

{
  "choices": [
    {
      "finish_reason": "stop",
      "index": 0,
      "message": {
        "content": "你好！很高兴和你聊天。\n\n有什么可以帮你的吗？或者想聊点什么？ 😊",
        "role": "assistant"
      }
    }
  ],
  "created": 1757472417,
  "id": "oebAaMTvMfCUjMcP_prYwAs",
  "model": "gemini-2.5-pro",
  "object": "chat.completion",
  "usage": {
    "completion_tokens": 21,
    "prompt_tokens": 3,
    "total_tokens": 1466
  }
}