ReferenceAPI
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POST
/v1/sessions/{session_id}/messagesAuthorization
serverToken AuthorizationBearer <token>
The server's BRAIN_API_TOKEN, sent as Authorization: Bearer . Required for application API calls when configured; optional only on a loopback server started without a token.
In: header
Path Parameters
session_id*string
Match
^ses_[A-Za-z0-9]{20,32}$Header Parameters
Idempotency-Key*string
Length
1 <= length <= 256Prefer?|
respond-async returns the committed turn_started event sequence; its idempotency scope is separate from synchronous sends
Request Body
application/json
TypeScript Definitions
Use the request body type in TypeScript.
Response Body
application/json
text/plain
application/json
curl -X POST "https://example.com/v1/sessions/string/messages" \ -H "Idempotency-Key: string" \ -H "Authorization: Bearer YOUR_TOKEN" \ -H "Content-Type: application/json" \ -d '{ "input": { "message": "string" } }'{ "last_sequence": 0, "session_id": "string", "status": "creating"}