> ## Documentation Index
> Fetch the complete documentation index at: https://docs.turncall.io/llms.txt
> Use this file to discover all available pages before exploring further.

# WebRTC

> Browser-based voice calls

TurnCall supports browser-based voice calls via WebRTC using Pipecat's SmallWebRTCTransport. Audio flows peer-to-peer at 16kHz.

## SDP Signaling

### Connect

Send an SDP offer and receive an answer:

```bash theme={null}
curl -X POST http://localhost:8090/v1/webrtc/connect \
  -H "Authorization: Bearer tc_xxx" \
  -H "Content-Type: application/json" \
  -d '{
    "sdp": "v=0...",
    "type": "offer",
    "requestData": {
      "agent_id": "AGENT_UUID"
    }
  }'
```

### ICE Trickle

```bash theme={null}
curl -X PATCH http://localhost:8090/v1/webrtc/connect \
  -H "Authorization: Bearer tc_xxx" \
  -H "Content-Type: application/json" \
  -d '{"candidate": "...", "sdpMid": "0", "sdpMLineIndex": 0}'
```

## Dynamic Routing

Pass `server_url` in `requestData` for pre-call initialization:

```json theme={null}
{
  "sdp": "v=0...",
  "type": "offer",
  "requestData": {
    "server_url": "https://your-server.com/turncall/init"
  }
}
```

See [Pre-Call Init](/guides/call-init) for response format.

## Browser Client

See the [examples/webrtc-client/](https://github.com/kobikis/turncall/tree/master/examples/webrtc-client) directory for a complete browser client using Pipecat JS SDK + WebRTC.

## Video Avatar

WebRTC cascade agents can add a lip-synced video avatar (HeyGen or Tavus). See [Video Avatar](/guides/video-avatar).