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

# Resemble AI

> Use the Resemble AI text-to-speech plugin in a Zero Runtime pipeline.

Resemble AI is a **text-to-speech** plugin. It turns the LLM's reply into audio the
caller hears, using Resemble AI's custom neural voice clones.

## Setup

Set your Resemble AI API key in the worker environment. Generate a key from the [Resemble AI dashboard](https://app.resemble.ai/account/api):

```bash theme={null}
export RESEMBLE_API_KEY=<key>
```

## Usage

Import the plugin and pass it to the pipeline's `tts` slot.

```python theme={null}
from zrt.plugins import ResembleTTS

tts = ResembleTTS()

# Pipeline(tts=tts, ...)
```

## Parameters

| Parameter     | Type          | Default      | Description                                                                                                                                                  |
| ------------- | ------------- | ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `api_key`     | `str \| None` | `None`       | Resemble AI API key. Falls back to the `RESEMBLE_API_KEY` environment variable when unset.                                                                   |
| `voice_uuid`  | `str`         | `"55592656"` | UUID of the Resemble AI voice (custom or pre-built) to use for synthesis. Retrieve voice UUIDs from the Resemble AI dashboard or the `/voices` API endpoint. |
| `sample_rate` | `int`         | `22050`      | Output audio sample rate in Hz.                                                                                                                              |

Spoken replies support interruptions. When the caller talks over the agent, the runtime
stops the audio and listens again. See the [plugins overview](/plugins/overview) for how TTS fits into the rest of the pipeline.