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# Reson8

> Configure Reson8 as your Vapi assistant's transcriber, including supported languages, keyterms, custom models, and turn detection settings.

Reson8 provides speech-to-text with built-in turn detection for Vapi voice agents.

You can use Reson8 through Vapi's default integration, or connect your own account in [Integrations](/providers/integrations).

## Supported capability

| Capability     | Provider value |
| -------------- | -------------- |
| Speech-to-text | `reson8`       |

## Speech-to-text

Set `transcriber.provider` to `reson8`. The optional `model` field accepts only `turns`, Reson8's turn detection endpoint. Set `language` to one language code, or to a comma-separated list such as `nl,en` to limit automatic language detection to those languages. Leave `language` out to detect the language on each utterance.

```bash
curl -X PATCH "https://api.vapi.ai/assistant/ASSISTANT_ID" \
  -H "Authorization: Bearer $VAPI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "transcriber": {
      "provider": "reson8",
      "model": "turns",
      "language": "nl,en",
      "keyterms": ["Vapi", "order number"]
    }
  }'
```

For additional API configuration options, review the [`Reson8Transcriber` fields](/api-reference/assistants/create#request.body.transcriber.Reson8Transcriber) in the Create Assistant API reference.

### Transcriber options

| Field                  | Required | Vapi behavior                          | Description                                                                     |
| ---------------------- | -------- | -------------------------------------- | ------------------------------------------------------------------------------- |
| `model`                | No       | Uses `turns`                           | The only accepted value is `turns`.                                             |
| `language`             | No       | Detects the language on each utterance | One language code, or a comma-separated list of candidate languages.            |
| `keyterms`             | No       | No keyterms                            | Up to 250 terms, such as brand names or product codes, to improve recognition.  |
| `customModelId`        | No       | No custom model                        | The ID of a phrase collection you manage in Reson8.                             |
| `eagerTurnProbability` | No       | Reson8's default, `0.5`                | The probability, from `0` to `1`, at which Reson8 flags a possible end of turn. |
| `finalTurnProbability` | No       | Reson8's default, `0.92`               | The probability, from `0` to `1`, at which Reson8 confirms the end of a turn.   |
| `fillerMode`           | No       | Reson8's default, `natural`            | How filler words appear in transcripts: `clean`, `natural`, or `verbatim`.      |

### Supported languages

| Language   | Language code |
| ---------- | ------------- |
| Dutch      | `nl`          |
| English    | `en`          |
| French     | `fr`          |
| Frisian    | `fy`          |
| German     | `de`          |
| Italian    | `it`          |
| Polish     | `pl`          |
| Portuguese | `pt`          |
| Spanish    | `es`          |
| Swedish    | `sv`          |

## Related

#### [Transcriber providers](/providers/transcriber/overview)

Compare every transcriber provider Vapi supports.

#### [Transcriber fallback](/customization/transcriber-fallback-plan)

Configure backup transcribers for your assistant.