Echo Mode

Create your first echo PAL and start a conversation in seconds.

Echo Mode lets you send text or audio input for the PAL to speak. This mode is best suited when your application doesn’t require speech recognition or perception capabilities or if you already use a custom ASR/Perception pipeline.

Note: External ASR systems are typically slower and less optimized than Tavus’ built-in pipeline.

Prerequisites

Before you begin, ensure the following dependencies are installed:

• flask
• daily-python

Create an Echo PAL

1. Step 1: Get an API Key

   1. Go to the PAL Maker and select API Key from the sidebar menu.
   2. Click Create New Key to begin generating your API key.
   3. Enter a name for the key and (optional) specify allowed IP addresses, then click Create API Key.
   4. Copy your newly created API key and store it securely.

   We cannot recover your API Key if you lose it.

2. Step 2: Create an Echo PAL

   Use the following request to create a PAL:

   cURL

   curl --request POST \
     --url https://tavusapi.com/v2/pals \
     --header 'Content-Type: application/json' \
     --header 'x-api-key: <api-key>' \
     --data '{
       "pal_name": "Echo Assistant",
       "pipeline_mode": "echo"
     }'
   
3. Step 3: Create a Conversation

   Create a conversation with your newly created pal_id:

   cURL

   curl --request POST \
     --url https://tavusapi.com/v2/conversations \
     --header 'Content-Type: application/json' \
     --header 'x-api-key: <api_key>' \
     --data '{
       "pal_id": "<your_pal_id>",
       "conversation_name": "Echo Test"
     }'
   
4. Step 4: Create an App

   Create a file named script.py and paste the following code:

   import sys
   from flask import Flask, jsonify, request
   from daily import CallClient, Daily, EventHandler
   
   app = Flask(__name__)
   
   # Global client instance
   call_client = None
   
   class RoomHandler(EventHandler):
       def __init__(self):
           super().__init__()
   
       def on_app_message(self, message, sender: str) -> None:
           print(f"Incoming app message from {sender}: {message}")
   
   def join_room(url):
       global call_client
       try:
           Daily.init()
           handler = RoomHandler()
           call_client = CallClient(event_handler=handler)
           call_client.join(url)
           print(f"Joined room: {url}")
       except Exception as e:
           print(f"Error joining room: {e}")
           raise
   
   @app.route("/send_text_message", methods=["POST"])
   def send_text_message():
       global call_client
       if not call_client:
           return jsonify({"error": "Not connected to a room"}), 400
   
       try:
           body = request.json
           conversation_id = body.get("conversation_id")
           properties = body.get("properties", {})
           message = {
               "message_type": "conversation",
               "event_type": "conversation.echo",
               "conversation_id": conversation_id,
               "properties": {
                   "modality": properties.get("modality", "text"),
                   "text": properties.get("text"),
                   "audio": properties.get("audio"),
                   "sample_rate": properties.get("sample_rate", 16000),
                   "inference_id": properties.get("inference_id"),
                   "done": properties.get("done")
               }
           }
           call_client.send_app_message(message)
           return jsonify({"status": "Message sent successfully"}), 200
       except Exception as e:
           return jsonify({"error": f"Failed to send message: {str(e)}"}), 500
   
   if __name__ == "__main__":
       if len(sys.argv) != 2:
           print("Usage: python script.py <conversation_url>")
           sys.exit(1)
   
       conversation_url = sys.argv[1]
       try:
           join_room(conversation_url)
           app.run(port=8000, debug=True)
       except Exception as e:
           print(f"Failed to start the application: {e}")
           sys.exit(1)
   

   This script starts a Flask app that connects to a Daily room and sends echo interaction messages to your PAL.

5. Step 5: Execute the Code

   Run the script:

   python script.py <conversation_url>
   

   Replace <conversation_url> with the URL returned when creating your conversation.

6. Step 6: Send Echo Message

   Send a POST request to your local server to trigger an echo message:

   cURL

   curl -X POST http://localhost:8000/send_text_message \
     -H "Content-Type: application/json" \
     -d '{
       "message_type": "conversation",
       "event_type": "conversation.echo",
       "conversation_id": "<conversation-id>",
       "properties": {
         "modality": "text",
         "text": "Hello there!",
         "inference_id": "inference-id-123",
         "done": true
       }
     }'
   

   In this example, the PAL will respond by saying: “Hello there!”