CHIRP | Rasa Documentation

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New in 3.17

The CHIRP channel is available from Rasa Pro 3.17.

Use the CHIRP channel to connect your assistant over a WebSocket audio stream. CHIRP is intended for automated voice testing — platforms that simulate callers and need a direct WebSocket connection rather than a telephony provider.

Like Twilio Media Streams, Rasa handles ASR and TTS on the server. Unlike telephony channels, there is no phone number or inbound webhook; the test client connects directly to your Rasa server.

Configuration

Add the following to credentials.yml:

chirp:
  server_url: "<your-domain>"
  username: "<username>"
  password: "<password>"
  asr:
    name: "deepgram"  # or "azure"
    # ASR-specific configuration
  tts:
    name: "deepgram"  # or "cartesia", "azure"
    # TTS-specific configuration
  interruptions:  # optional
    enabled: true
    min_words: 3

WebSocket endpoint

The test client connects to:

wss://<your-domain>/webhooks/chirp/websocket

Use HTTP Basic Authentication with the username and password from credentials.yml.

Protocol

Audio is sent in both directions as 16 kHz, signed 16-bit mono PCM in WebSocket binary frames. Optional JSON text frames (speech.started, speech.completed) signal turn boundaries and support interruption handling.