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

# Agent Builder

Prototype voice agents in the Playground. Test prompts, configure voices, and deploy in seconds.

## Create your agent

Go to [play.cartesia.ai/agents](https://play.cartesia.ai/agents) and select **Start in Playground**.

<Frame>
  <img src="https://mintcdn.com/cartesia-2650f86a/bcE0PrYtfJKz4Yg4/assets/images/agents/create-from-playground.png?fit=max&auto=format&n=bcE0PrYtfJKz4Yg4&q=85&s=8fa65f495726ce9df7c4679a47455f27" alt="Create your first voice agent options" width="1784" height="974" data-path="assets/images/agents/create-from-playground.png" />
</Frame>

Customize your agent's behavior, voice, and greeting.

<Frame>
  <img src="https://mintcdn.com/cartesia-2650f86a/bcE0PrYtfJKz4Yg4/assets/images/agents/dynamic-configure-agent.png?fit=max&auto=format&n=bcE0PrYtfJKz4Yg4&q=85&s=0717dbbadf54d6377e304e023d6ef936" alt="Dynamic agent configuration interface" width="2100" height="1548" data-path="assets/images/agents/dynamic-configure-agent.png" />
</Frame>

**System Prompt** — Define your agent's role and guidelines. You can also provide a natural language description of your agent and the platform will generate a structured system prompt.

**Voice** — Choose from Cartesia's voice library. Preview voices before selecting.

**Initial Message** — Set the greeting your agent speaks when calls start. Check **Skip agent introduction** to have the agent wait for the user to speak first.

**Background Sound** — Add ambient audio for call center atmospheres or office environments.

**Preview** changes before publishing.

## Continue building in code

Connect your Playground agent to GitHub to customize with code.

<Steps>
  <Step title="Connect to GitHub">
    On your agent page, click **Connect to GitHub**. Authorize Cartesia to create a repository.
  </Step>

  <Step title="Clone locally">
    ```bash theme={null}
    git clone https://github.com/your-org/your-agent.git
    cd your-agent
    ```
  </Step>

  <Step title="Install dependencies">
    ```bash theme={null}
    uv pip install .
    ```
  </Step>

  <Step title="Edit your agent">
    Open `main.py` to add tools, custom logic, or modify the prompt.
  </Step>

  <Step title="Deploy">
    Push to deploy your changes.

    ```bash theme={null}
    git push
    ```
  </Step>
</Steps>

## Next steps

<CardGroup cols={2}>
  <Card title="Quickstart" icon="rocket" href="/line/start-building/quickstart">
    Build agents with the SDK
  </Card>

  <Card title="Agents" icon="robot" href="/line/sdk/agents">
    Prompts, voices, and pre-call configuration
  </Card>
</CardGroup>