Webhook events

Each event is also saved on the call’s timeline (GET /api/v1/calls/{id}/events), with the same type, message, level, latency_ms and data.

Order of events

A typical outbound call:

call.queued → call.dequeued → call.placed → call.started → welcome → tts.first_audio
→ user.turn → llm.first_token → tts.first_audio → agent.reply
→ user.turn → llm.first_token → tool.call → tool.result → tts.first_audio → agent.reply
→ ... → tool.call (end_call) → call.ended → call.completed

Inbound and browser calls start at call.started. A call that never connects ends with call.ended and has no call.completed.

All events

Event	When	Extra data fields
call.queued	An outbound call joined the queue.	position, by
call.dequeued	A slot was free and the call is about to be dialled. latency_ms is how long it waited.
call.placed	Plivo accepted the dial request.
call.started	The call connected and the agent is live.	channel, from, to, stt, llm, tts, started_by, values
welcome	The agent starts saying its welcome message (the text is in message).
tts.first_audio	The agent’s first audio of a reply played. latency_ms is from the caller finishing to this moment.	welcome: true for the welcome message
user.turn	The caller finished a turn (message is what they said).	after_goodbye: true if said after the agent decided to hang up
llm.first_token	The LLM started answering. latency_ms is from the caller finishing.	model_ms: time since the LLM request was sent
agent.reply	The agent finished a reply (message is the full text).
interrupted	The caller talked over the agent, which stopped (message is what the caller heard).
tool.call	The agent called a tool.	name, args, url (name only for end_call)
tool.result	The tool answered or failed. latency_ms is the request time. level is warning unless the status is 2xx.	name, status, result
user.online_check	The agent asked whether the caller is still there.
hangup.prompt	The hang-up prompt decided the conversation is over.
error	Something went wrong. level is warning or error.	Sometimes provider
call.ended	The call ended, for any reason.	see below
call.completed	The final call record is saved, after post-call analytics.	call
ping	A test from POST /api/v1/webhooks/{id}/test.

call.started

{
  "type": "call.started",
  "data": {
    "message": "outbound call with Appointment reminder",
    "level": "info",
    "latency_ms": null,
    "channel": "phone",
    "from": "+918035001234",
    "to": "+919812345678",
    "stt": "cartesia/ink-2",
    "llm": "gemini-3.5-flash-lite",
    "tts": "sonic-3.6/Riya",
    "started_by": "",
    "values": ["customer_name", "slot"]
  }
}

values lists the user_data keys the call has (not their values). started_by is the person’s name for browser calls.

tool.result

{
  "type": "tool.result",
  "data": {
    "message": "check_availability -> HTTP 200",
    "level": "info",
    "latency_ms": 184,
    "name": "check_availability",
    "status": 200,
    "result": {"status": 200, "result": {"free_slots": ["10:30", "12:00"]}}
  }
}

result is what the LLM received (see Tools), cut to about 3000 characters. status is 0 when your endpoint did not answer.

call.ended

When a call that connected ends:

{
  "type": "call.ended",
  "data": {
    "message": "ended by agent: agent ended the call",
    "level": "info",
    "latency_ms": null,
    "duration_seconds": 14.2,
    "avg_first_audio_ms": 1050,
    "usage": {"stt_seconds": 14.0, "tts_characters": 121, "llm_input_tokens": 1840, "llm_output_tokens": 41, "llm_calls": 1}
  }
}

level is error when the call ended because of an error.

When a call never connected, message says why and there is no usage:

Case	message	level	Extra
Plivo reported no answer, busy, failed or canceled	not connected: no-answer	warning	plivo: Plivo’s status
Canceled while queued	canceled while queued	info
Expired, out of credits, agent deleted, dial refused	the hangup_reason	warning (error for credits and refusals)

call.completed

Sent once per connected call, after post-call analytics, with the full call object plus transcript_text:

{
  "id": "evt_1f2e3d4c5b6a79880a1b2c3d4e5f6a7b",
  "type": "call.completed",
  "created_at": "2026-10-01T09:14:21.733000+00:00",
  "workspace_id": "6df74233a1b04c2e9f8d7c6b5a4e3d2c",
  "call_id": "00b1d622a8f04f4f8f3a3c2d9e5b7a11",
  "agent_id": "1b81a241c0e44f5c9d1f0e2a7c3b9d10",
  "data": {
    "message": "call completed",
    "level": "info",
    "latency_ms": null,
    "call": {
      "id": "00b1d622a8f04f4f8f3a3c2d9e5b7a11",
      "agent_name": "Appointment reminder",
      "direction": "outbound",
      "to_number": "+919812345678",
      "status": "completed",
      "user_data": {"customer_name": "Rohan", "slot": "11 am"},
      "transcript": [{"role": "assistant", "text": "Hello Rohan, ...", "at": "2026-10-01T09:14:02.410000Z", "interrupted": false}],
      "transcript_text": "assistant: Hello Rohan, ...\nuser: Yes, I'll be there at eleven.\nassistant: Great, we'll see you tomorrow at 11 am. Goodbye!",
      "duration_seconds": 14.2,
      "cost_paise": 95,
      "hangup_by": "agent",
      "hangup_reason": "agent ended the call",
      "summary": "City Clinic called Rohan to confirm tomorrow's 11 am appointment. ...",
      "extracted": {"confirmed": true, "new_day": null},
      "...": "..."
    }
  }
}

Times in webhooks are in UTC. This is the event to use for syncing results to your CRM: it has the outcome, the transcript, the analytics and the cost in one place.

ping

{
  "id": "evt_ping",
  "type": "ping",
  "created_at": "2026-10-01T09:30:00.000000+00:00",
  "workspace_id": "6df74233a1b04c2e9f8d7c6b5a4e3d2c",
  "call_id": "",
  "agent_id": "",
  "data": {"message": "Test event from Voxa"}
}