### Install Dependencies and Run Server

Source: https://github.com/heygen-official/streamingavatar/blob/main/README.md

Install the necessary Node.js dependencies (like Express) and then start the demo server. The server will listen on port 3000.

```Shell
npm install express
node server.js
```

--------------------------------

### Clone Streaming Avatar Repository

Source: https://github.com/heygen-official/streamingavatar/blob/main/README.md

Instructions to clone the HeyGen Streaming Avatar GitHub repository to your local machine, which contains the demo application.

```Shell
git clone https://github.com/HeyGen-Official/StreamingAvatar.git
```

--------------------------------

### Configure HeyGen API Key in index.js

Source: https://github.com/heygen-official/streamingavatar/blob/main/README.md

Update the `index.js` file with your HeyGen API Key or Trial Token. This key is essential for the demo to connect to the HeyGen Streaming API.

```JavaScript
"apiKey": "YourApiKey";
```

--------------------------------

### Configure OpenAI API Key for Talk Mode

Source: https://github.com/heygen-official/streamingavatar/blob/main/README.md

Optionally set your OpenAI API key in the `server.js` file to enable the 'Talk' mode feature, allowing the avatar to respond using OpenAI's models.

```JavaScript
const openai = new OpenAI({
  apiKey: "<your openai api key>",
});
```

--------------------------------

### API Reference: List Voices v2 Endpoint

Source: https://github.com/heygen-official/streamingavatar/blob/main/README.md

Reference to the HeyGen API endpoint for listing available AI voices. This endpoint helps you find Voice IDs compatible with the Streaming API.

```APIDOC
Endpoint: https://docs.heygen.com/reference/list-voices-v2
Purpose: Retrieve IDs for AI Voices compatible with the Streaming API.
```

--------------------------------

### API Reference: List Sessions Endpoint

Source: https://github.com/heygen-official/streamingavatar/blob/main/README.md

Reference to the HeyGen API endpoint for checking the number of active streaming sessions. Useful for monitoring concurrent session limits.

```APIDOC
Endpoint: https://docs.heygen.com/reference/list-sessions
Purpose: Check the number of active streaming sessions.
```

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