Sign in

v27

latestOpenAPI 3.1.0raw.githubusercontent.com2026-07-2193427579.9 KB
Messages

Create a message.

Create a message using the Anthropic Messages API format.

post/v1/messages

Request body

modelstring required

The model to use for generation.

max_tokensinteger required

The maximum number of tokens to generate.

streamboolean

Whether to stream the response.

temperaturenumber

Sampling temperature.

top_pnumber

Nucleus sampling parameter.

top_kinteger

Top-k sampling parameter.

stop_sequencesstring[]

Custom stop sequences.

metadataobject

Request metadata.

service_tierstring

Service tier to use.

Response

An AnthropicMessageResponse or a stream of Anthropic SSE events.

idstring required

Unique message ID (msg_ prefix).

type'message'
role'assistant'
modelstring required
stop_reasonstring nullable

Why the model stopped: end_turn, stop_sequence, tool_use, or max_tokens.

stop_sequencestring nullable