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POST
Use this endpoint when your application, SDK, or agent expects the Anthropic Messages request and response format. Send a standard Messages payload with model, messages, and max_tokens. Capriole AI resolves latest aliases to the selected upstream Claude model before upstream dispatch, forwards compatible fields such as system, tools, thinking, and stream, and returns the upstream JSON or SSE stream unchanged. POST /v1/messages accepts claude-latest, claude-opus-4-8, claude-opus-4-7, claude-opus-4-6, and claude-sonnet-4-6. Use claude-latest to let Capriole AI choose our recommended flagship Claude Messages model. POST /v1/messages/count_tokens accepts the same Claude model IDs for Anthropic-compatible token-count checks. It returns the selected upstream’s token-count response or error. For simple Capriole-native text generation, use POST /v1/chat. Use POST /v1/messages when Anthropic Messages wire behavior is required.

Authorizations

Authorization
string
header
required

Use an API key created in the Capriole AI page. Send it as Authorization: Bearer sk-....

Body

application/json
model
enum<string>
required

Public Anthropic Messages model identifier or Claude latest alias

Available options:
claude-latest,
claude-opus-4-8,
claude-opus-4-7,
claude-opus-4-6,
claude-sonnet-4-6
messages
object[]
required

Anthropic-compatible conversation messages.

max_tokens
integer
required

Maximum number of output tokens.

system

Optional Anthropic-compatible system prompt.

tools
object[]

Anthropic-compatible tool definitions.

thinking
object

Anthropic-compatible thinking options.

stream
boolean
default:false

Stream the response as Anthropic-compatible server-sent events.

Response

Anthropic Messages-compatible JSON response or SSE stream

Anthropic Messages-compatible response body.