Make an outbound call | FormantAI

curl -X POST https://api.voice.formantai.com/v1/call \
     -H "Authorization: Bearer <token>" \
     -H "Content-Type: application/json" \
     -d '{
  "agent_id": 456,
  "parameters": [
    {
      "name": "customer_phone",
      "value": "+14155552671"
    }
  ],
  "scheduled_for": "2026-04-08T14:00:00Z"
}'

{
  "data": {
    "agent_id": 456,
    "conversation_id": "a3f47b9e-8c2d-4f1a-9b7e-2d5f3c6a7b8e",
    "retry_context": {
      "collected_data": {},
      "retry_initial_message": "We missed you on the last call, would you like to reschedule?",
      "retry_language": "en-US",
      "retry_stage_id": "stage_02"
    },
    "scheduled_for": "2026-04-08T14:00:00Z",
    "status": "scheduled",
    "trace_id": "9f8b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d"
  }
}

Initiates one outbound call with a configured FormantAI Voice agent.

Authentication

AuthorizationBearer

Bearer authentication of the form Bearer <token>, where token is your auth token.

Request

This endpoint expects an object.

agent_idintegerRequired

parameterslist of objectsRequired

conversation_idstring or nullOptional

idempotency_keystring or nullOptional

metadatastring or nullOptional

retry_contextobjectOptional

scheduled_fordatetime or nullOptional

Response

Call accepted

dataobject

Errors

400

Bad Request Error

401

Unauthorized Error

404

Not Found Error

409

Conflict Error

429

Too Many Requests Error