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

# ElevenLabs Speech to Text

> Transcribe audio and video to text with diarization, event tagging, and auto language detection

## What it does

Transcribes audio or video to text using [ElevenLabs Scribe](https://elevenlabs.io/speech-to-text). Works on files already in the conversation (including output from [elevenlabs\_text\_to\_speech](/tools/elevenlabs_text_to_speech)) or any HTTPS-accessible media URL — including cloud storage, YouTube, TikTok, and podcast hosts.

## Key features

* Single `audio_source` param accepts `r2://` conversation attachments **or** HTTPS URLs — auto-detected by prefix
* Scribe v2 (default) for best-in-class accuracy
* Word-level timestamps returned by default
* Speaker diarization (who spoke when) when `diarize` is on
* Audio event tagging — surfaces `(laughter)`, `(footsteps)`, etc. inline in the transcript
* Auto language detection, or pin a specific ISO-639 code

## Parameters

| Parameter                | Type    | Required | Description                                                                                                                                                                                                                      |
| ------------------------ | ------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `audio_source`           | string  | Yes      | Either (a) an `r2://bucket/key` path of an audio file already attached to the thread, or (b) an HTTPS URL to an audio/video file. Supports cloud storage URLs (S3, R2, GCS), YouTube, TikTok, and other HTTPS sources up to 2GB. |
| `model_id`               | enum    | No       | `scribe_v2` (default, latest) or `scribe_v1`                                                                                                                                                                                     |
| `language_code`          | string  | No       | ISO-639-1 or ISO-639-3 code (e.g. `eng`, `spa`). If omitted, the language is auto-detected.                                                                                                                                      |
| `diarize`                | boolean | No       | Annotate which speaker is talking (returns `speaker_id` per word). Default: `true`                                                                                                                                               |
| `tag_audio_events`       | boolean | No       | Tag audio events like `(laughter)`, `(footsteps)` inline. Default: `true`                                                                                                                                                        |
| `num_speakers`           | integer | No       | Expected maximum number of speakers (1–32). Helps diarization when known.                                                                                                                                                        |
| `timestamps_granularity` | enum    | No       | `none`, `word` (default), or `character`                                                                                                                                                                                         |

## Common use cases

### Transcribe a file already attached to the conversation

```
audio_source: "r2://aster-agents/org_xxx/threads/yyy/recording.mp3"
```

Use this when a previous tool call (TTS, a document extraction, or a user upload) produced an audio file — pass its `r2_path` straight through.

### Transcribe a public podcast or recording URL

```
audio_source: "https://example.com/episode-42.mp3"
language_code: "eng"
```

### Transcribe a meeting with multiple speakers

```
audio_source: "r2://aster-agents/org_xxx/threads/yyy/meeting.mp4"
diarize: true
num_speakers: 4
```

## Response

Returns:

* `text` — the full transcript
* `language_code` / `language_probability` — detected language and confidence
* `speaker_count` — number of distinct speakers identified (when `diarize` is on)
* `word_count` — total words in the transcript
* `words` — per-word objects with text, start/end timestamps, and `speaker_id`
* `source` — a label describing which input path was used

## Setup

No per-user setup. ElevenLabs is configured at the platform level — just enable the tool on your agent in **Control Hub > Edit Agent** under the **Audio** section.