Messages API

POST /v1/messages

Compatible with the Anthropic Messages API. The gateway transparently proxies to Claude models via the configured Anthropic or Bedrock channel.

Request Body

Parameter	Type	Description
`model`*	`string`	ID of the model to use (e.g. claude-sonnet-4-6).
`messages`*	`array`	Array of message objects with role (user/assistant) and content.
`max_tokens`*	`integer`	Maximum number of tokens to generate.
`system`	`string`	System prompt to set context for the conversation.
`stream`	`boolean`	If true, return a stream of SSE events. Default: false.
`temperature`	`number`	Sampling temperature 0–1. Default: 1.
`tools`	`array`	List of tool definitions for tool use.

Example Request

POST /v1/messages
Authorization: Bearer YOUR_API_KEY
x-api-key: YOUR_API_KEY

{
  "model": "claude-sonnet-4-6",
  "max_tokens": 256,
  "messages": [
    {"role": "user", "content": "What is the capital of France?"}
  ]
}

Example Response

{
  "id": "msg_abc123",
  "type": "message",
  "role": "assistant",
  "model": "claude-sonnet-4-6",
  "content": [
    { "type": "text", "text": "The capital of France is Paris." }
  ],
  "stop_reason": "end_turn",
  "usage": {
    "input_tokens": 14,
    "output_tokens": 9
  }
}

ℹ

The Messages API accepts both Authorization: Bearer and x-api-key headers for authentication, matching the Anthropic SDK convention.