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

# Utterance End

> Use the utterance end flag to detect the end of speech

The Utterance End feature can be used to detect the end of speech by waiting a configured amount of milliseconds of silence after the last detected speech.

The end of speech is detected using a combination between the VAD (Voice Activity Detection) and the transcription model. The transcription model is also used to prevent false positives of speech detection by VAD.

## Configuration

The Utterance End feature can be configured by using the `utteranceEnd=1000` query parameter, where `1000` is the amount of milliseconds of silence to wait after the last detected speech.

## Result

When an utterance is ended, a [transcription response](/api-reference/schemas/egress/transcription-response) with the `"utterance": true` attribute is emitted. The content of the response can be a transcription response or an empty transcription, depending on the underlying engine implementation.

```json theme={null}
{
  "transcription": "",
  "words": [],
  "start": 6480,
  "end": 6480,
  "metadata": {},
  "utterance": true
}
```