Stream conversation events to your WebSocket

curl -X POST https://api.telnyx.com/v2/ai/assistants/{assistant_id} \
  -H "Authorization: Bearer $TELNYX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "websocket_settings": {
      "enabled": true,
      "url": "wss://events.example.com/telnyx",
      "auth_ref": "my_websocket_token"
    }
  }'

Telnyx → You      (connect wss://events.example.com/telnyx, Authorization: Bearer ...)
Telnyx → You      {"type":"session.created","session":{...}}
Telnyx → You      {"type":"telnyx.call.answered","call_control_id":"..."}
Telnyx → You      {"type":"conversation.item.created","item":{"role":"user", ...}}
Telnyx → You      {"type":"response.created","response":{"id":"resp_9c1f4a2b", ...}}
Telnyx → You      {"type":"response.text.delta","delta":"We are open ", ...}
You    → Telnyx   {"type":"conversation.item.create","item":{"role":"user", ...}}
Telnyx → You      {"type":"telnyx.call.hangup","cause":"normal_clearing", ...}
Telnyx → You      {"type":"session.ended","reason":"normal","duration_sec":84, ...}

const buffers = new Map();

function onEvent(event) {
  if (event.type === "response.text.delta") {
    const key = `${event.item_id}:${event.content_index}`;
    buffers.set(key, (buffers.get(key) ?? "") + event.delta);
  }
  if (event.type === "conversation.item.created" && event.item.role === "assistant") {
    // The completed item carries the final text — use it as the source of truth.
    console.log(event.item.content[0]?.text);
  }
}

{
  "type": "conversation.item.create",
  "item": {
    "type": "message",
    "role": "user",
    "content": [{ "type": "input_text", "text": "Actually, make that a delivery instead." }]
  }
}

import { WebSocketServer } from "ws";

const wss = new WebSocketServer({ port: 8080 });

wss.on("connection", (socket, request) => {
  // Verify the credential Telnyx sends from your `auth_ref` secret.
  if (request.headers.authorization !== `Bearer ${process.env.TELNYX_WS_TOKEN}`) {
    socket.close(1008, "unauthorized");
    return;
  }

  let conversationId = null;

  socket.on("message", (data) => {
    const event = JSON.parse(data.toString());

    switch (event.type) {
      case "session.created":
        conversationId = event.session.conversation_id;
        console.log(`conversation ${conversationId} started`);
        break;

      case "conversation.item.created":
        console.log(`[${event.item.role}]`, event.item.content[0]?.text);
        break;

      case "session.ended":
        console.log(`ended: ${event.reason} after ${event.duration_sec}s`);
        break;

      default:
        // New event types can appear at any time — ignore what you don't know.
        break;
    }
  });
});