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POST

Claude Messages API

The Claude Messages API preserves Anthropic’s native request structure and is suitable for migrating existing Claude SDK-based services or services using native prompt structures. Requests will be routed into the Claude relay format and dispatched to the corresponding upstream based on the channel.

Authentication

You can also use Claude native request headers:

Request Body

string
required
Claude model name.
array<object>
required
Array of conversation messages. In Claude’s native format, message roles are typically user or assistant.
string | array<object>
System prompt. Claude does not use system role messages; instead, system instructions are passed through this field.
integer
Maximum number of output tokens. Most Claude requests should pass this explicitly.
boolean
Whether to enable SSE streaming output.
number
Sampling temperature.
number
Top-p sampling parameter.
integer
Top-K sampling parameter.
array<string>
Stop sequences.
array<object>
Claude tool list, typically including name, description, and input_schema.
object
Controls the tool selection strategy, for example { "type": "tool", "name": "get_weather" }.
object
Extended thinking configuration, for example { "type": "enabled", "budget_tokens": 10000 }.
object
Business-side metadata, such as user_id.

Request Example

Multimodal Input

Tool Calling

Response Example