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API Reference 8 min read

Chat Completions API

Endpoint

POST /v1/chat/completions

Request Body

{
  "model": "gpt-4o",
  "messages": [
    {"role": "system", "content": "You are a helpful assistant."},
    {"role": "user", "content": "What is the capital of France?"}
  ],
  "temperature": 0.7,
  "max_tokens": 1000
}

Response

{
  "id": "chatcmpl-abc123",
  "object": "chat.completion",
  "created": 1700000000,
  "model": "gpt-4o",
  "choices": [
    {
      "index": 0,
      "message": {"role": "assistant", "content": "The capital of France is Paris."},
      "finish_reason": "stop"
    }
  ],
  "usage": {"prompt_tokens": 20, "completion_tokens": 8, "total_tokens": 28}
}

Streaming

Set stream: true for server-sent events.