Consumer-initiated call flow

Updated: Mar 23, 2026

This walkthrough shows a complete consumer-initiated call flow, from receiving the incoming call to ending it.

Before you begin

Complete the setup described in the Calling overview

Subscribe to the calls webhook field

Receive the connect webhook

When a consumer calls your Page from the Messenger app, you receive a connect webhook:

{
  "object": "page",
  "entry": [
    {
      "id": "{page-id}",
      "time": 1671644824,
      "calls": [
        {
          "id": "c_M5YPhGE5jm0L_PMQdScLlYJlR7tU_f0rgXiTQ",
          "to": "106378625516323",
          "from": "5275811702471834",
          "event": "connect",
          "timestamp": 1671644824,
          "call_direction": "user_initiated"
        }
      ]
    }
  ]
}

Accept the call

Respond within 60 seconds by calling the /calls API with an SDP offer:

POST /{page-id}/calls
{
  "call_id": "c_M5YPhGE5jm0L_PMQdScLlYJlR7tU_f0rgXinCqnTQ",
  "action": "accept",
  "session" : {
     "sdp" : "<<RFC 4566 SDP>>",
     "sdp_type" : "offer"
  }
}

You receive an SDP answer in the response:

{
  "success" : true,
  "session" : {
    "sdp_response" : "<<RFC 4566 SDP>>",
    "sdp_renegotiation" : "<<RFC 4566 SDP>>"
  }
}

Establish the WebRTC connection

Apply the response and renegotiation offer to your local peer connection:

fetch(url, data).then(response => {
  response.json().then(data => {
    pc.setRemoteDescription(new RTCSessionDescription({
      sdp: data.session.sdp_response.sdp, type: 'answer'
    }));
    pc.setRemoteDescription(new RTCSessionDescription({
      sdp: data.session.sdp_renegotiation.sdp, type: 'offer'
    }));
    pc.createAnswer().then(answer => {
      pc.setLocalDescription(answer);
    });
  })
});

The call is now connected.

Terminate the call

To end the call, send a terminate request:

POST /{page-id}/calls
{
  "call_id": "c_M5YPhGE5jm0L_PMQdScLlYJlR7tU_f0rgXinCqnTQ",
  "action" : "terminate"
}

You receive a confirmation:

{
  "success" : true
}

Receive the terminate webhook

After the call ends (whether you terminated it or the consumer hung up), you receive a terminate webhook:

{
  "object": "page",
  "entry": [
    {
      "id": "{page-id}",
      "time": 1671644824,
      "calls": [
        {
          "id": "c_M5YPhGE5jm0L_PMQdScLlYJlR7tU_f0rgXiTQ",
          "event": "terminate",
          "timestamp": 1671644824,
          "status" : "Completed",
          "start_time" : 1671644824,
          "end_time" : 1671644944,
          "duration" : 120
        }
      ]
    }
  ]
}