Voice Agent

• Speech-to-text (STT) - for understanding speech inputs
• LLM - for generating the agent text response
• Text-to-speech (TTS) - for generating agent speech audio

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Prerequisites

• Node.js v20 or higher: Download here
• Assembly.AI API key (required for speech-to-text functionality): Get your API key
• Inworld API key (required): Sign up here or see quickstart guide

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Run the Template

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Start the Server

1. Clone the Voice Agent GitHub repo:
   git clone https://github.com/inworld-ai/voice-agent-node
   cd voice-agent-node
   
2. Navigate to the server directory:
   cd server
   
3. Copy the .env-sample file to .env:
   cp .env-sample .env
   
4. Configure your .env file with required API keys:
   .env

   # Required, Inworld Agent Runtime Base64 API key
   INWORLD_API_KEY=<your_api_key_here>
   
   # Required, get your Assembly.AI API key from https://www.assemblyai.com/
   ASSEMBLY_AI_API_KEY=<your_assemblyai_api_key_here>
   
   Get your Assembly.AI API key for speech-to-text functionality.
5. Install dependencies:
   npm install
   
6. Start the server:
   npm start
   
   The server will start on port 4000.

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Start the Client

1. Open a new terminal window.
2. Navigate to the client directory:
   cd client
   
3. (Optional) Create a .env file to customize client behavior:
   .env

   # Optional: Enable latency reporting in the UI
   VITE_ENABLE_LATENCY_REPORTING=true
   
   # Optional: Server port (default: 4000)
   VITE_APP_PORT=4000
   
4. Install dependencies:
   npm install
   
5. Start the client:
   npm start
   
   The client will start on port 3000 (or the next available port if 3000 is in use) and should automatically open in your default browser.

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Chat with Your Agent

1. Configure the agent:
   • Enter the agent system prompt
   • Click “Create Agent”
2. Start chatting:
   • Voice input: Click the microphone icon to unmute yourself, speak, then click again to mute
   • Text input: Type in the input field and press Enter to send
3. Monitor performance:
   • View dashboards, traces, and logs in the Inworld Portal
   • Enable VITE_ENABLE_LATENCY_REPORTING=true in client .env to see latency metrics in the UI

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Next steps