> ## Documentation Index
> Fetch the complete documentation index at: https://heygen-1fa696a7.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Avatar V

> Avatar V is HeyGen's highest-fidelity v3 rendering engine, using cross-reference-driven animation for the most natural motion and lip-sync. Opt-in per look.

## Supported avatar types

`digital_twin` only — subject to eligibility.

## Supported parameters

* `motion_prompt` — natural-language control of body motion and hand gestures.
* `reference_look_id` *(optional)* — an `instant_avatar` look to use as the animation reference. Must belong to the same avatar group as `avatar_id`. When omitted, the digital twin self-references.

**Not supported (Avatar IV only):** `expressiveness`.

## Checking eligibility

Not every avatar look supports Avatar V. Before using it, fetch the look and check `supported_api_engines`:

```bash theme={null}
GET /v3/avatars/looks/{look_id}
```

```json theme={null}
{
  "id": "lk_abc123",
  "name": "My Digital Twin",
  "avatar_type": "digital_twin",
  "supported_api_engines": ["avatar_iv", "avatar_v"]
}
```

Avatar V is only available if `"avatar_v"` appears in `supported_api_engines`. Requesting it for an ineligible look returns a `400` error.

## Example

```json theme={null}
{
  "type": "avatar",
  "avatar_id": "YOUR_LOOK_ID",
  "script": "Hello from Avatar V.",
  "voice_id": "YOUR_VOICE_ID",
  "resolution": "1080p",
  "engine": { "type": "avatar_v" }
}
```

See the [Digital Twin guide](/generate-avatar-video) for the end-to-end request and polling flow, [Models](/models) for an engine comparison, or [Avatar IV](/avatar-iv) for the default engine.