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

# download_audio

> Extract audio from any URL at maximum speed.

Supports YouTube, Vimeo, TikTok, Twitter, SoundCloud, and 1000+ sites.

***

## Speed Optimizations

* aria2c multi-connection downloads (16 parallel connections)
* Concurrent fragment downloading (4 fragments)
* No video download, audio extraction only (up to 200x faster than downloading full video)
* No format conversion, native audio format preserved

***

## Example

**Request:**

```json theme={null}
{
  "url": "https://youtube.com/watch?v=xxx",
  "output_dir": "~/Downloads"
}
```

**Response:**

```json theme={null}
{
  "success": true,
  "url": "https://youtube.com/watch?v=xxx",
  "output_dir": "/Users/you/Downloads",
  "file": {
    "path": "/Users/you/Downloads/Video_Title_dQw4w9WgXcQ.webm",
    "filename": "Video_Title_dQw4w9WgXcQ.webm",
    "size_mb": 14.49
  },
  "aria2c_used": true,
  "message": "Audio downloaded to /Users/you/Downloads/Video_Title_dQw4w9WgXcQ.webm"
}
```

***

## Parameters

| Parameter    | Required | Default       | Description                                                     |
| ------------ | -------- | ------------- | --------------------------------------------------------------- |
| `url`        | Yes      | —             | Video URL to download audio from (YouTube, Vimeo, TikTok, etc.) |
| `output_dir` | No       | `~/Downloads` | Directory to save the audio file                                |

***

## Notes

<Tip>The downloaded file path is ready to pass directly to `transcribe_audio` or `search_audio`.</Tip>

<Tip>Audio format depends on the source. YouTube returns `.webm`, SoundCloud returns `.m4a`, etc. No conversion is done, keeping downloads fast.</Tip>

<Tip>Filenames are sanitized to ASCII characters only — spaces, smart quotes, and special characters are replaced with underscores. This prevents file path issues when passing downloads to other tools.</Tip>