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

# HeyGen Video Agent V3

> Generate videos with a single prompt. Describe what you want in plain text, and the agent handles avatar selection, scripting, scene composition - all in one.

<Info>
  Pricing: **\$0.034/second**. Endpoint: `POST /v1/models/heygen/v3/video-agent/runs`.
</Info>

Generate videos with a single prompt. Describe what you want in plain text, and the agent handles avatar selection, scripting, scene composition - all in one.

## Overview

* **Endpoint**: [https://api.runflow.io/v1/models/heygen/v3/video-agent/runs](https://api.runflow.io/v1/models/heygen/v3/video-agent/runs)
* **Model ID**: heygen/v3/video-agent
* **Provider**: HeyGen
* **License**: commercial
* **Last Updated**: 2026-04-21

## Pricing

* **Base price**: \$0.034/second
* **Note**: Usage-based, per second of generated video

# HeyGen Video Agent V3 API

**Endpoint:** `POST /v1/models/heygen/v3/video-agent/runs`

## Run the model

### Python

```python theme={"dark"}
import requests

response = requests.post(
    "https://api.runflow.io/v1/models/heygen/v3/video-agent/runs",
    headers={"Authorization": "Bearer RUNFLOW_API_KEY"},
    json={
        "input": {
            "prompt": "Create a 20-second professional product announcement video from a CTO introducing a new AI video platform to prospective customers. Modern office backdrop, warm professional lighting, confident tone, medium shot, minimal graphics. End with call-to-action."
        },
        "callback_url": "https://your-server.com/webhook"
    },
)

data = response.json()
print(data)
```

### Node.js

```javascript theme={"dark"}
const response = await fetch(
  "https://api.runflow.io/v1/models/heygen/v3/video-agent/runs",
  {
    method: "POST",
    headers: {
      "Authorization": "Bearer RUNFLOW_API_KEY",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
        "input": {
            "prompt": "Create a 20-second professional product announcement video from a CTO introducing a new AI video platform to prospective customers. Modern office backdrop, warm professional lighting, confident tone, medium shot, minimal graphics. End with call-to-action."
        },
        "callback_url": "https://your-server.com/webhook"
    }),
  }
);

const data = await response.json();
console.log(data);
```

### cURL

```bash theme={"dark"}
curl -X POST https://api.runflow.io/v1/models/heygen/v3/video-agent/runs \
  -H "Authorization: Bearer $RUNFLOW_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'JSON'
{
    "input": {
        "prompt": "Create a 20-second professional product announcement video from a CTO introducing a new AI video platform to prospective customers. Modern office backdrop, warm professional lighting, confident tone, medium shot, minimal graphics. End with call-to-action."
    },
    "callback_url": "https://your-server.com/webhook"
}
JSON
```

## Request parameters

| Parameter      | Type           | Required | Description                                                 |
| -------------- | -------------- | -------- | ----------------------------------------------------------- |
| `input`        | object         | required | Model input parameters. See "Input schema" below.           |
| `callback_url` | string \| null | optional | Webhook URL - POSTed when the run reaches a terminal state. |
| `metadata`     | object \| null | optional | Arbitrary key-value pairs attached to the run.              |

## Input schema

| Field            | Type       | Required | Allowed values          | Description                                                                                                                         |
| ---------------- | ---------- | -------- | ----------------------- | ----------------------------------------------------------------------------------------------------------------------------------- |
| `prompt`         | string     | required | Any                     | Natural language prompt describing the video to generate. The agent handles avatar selection, script, and production automatically. |
| `orientation`    | string     | optional | `landscape`, `portrait` | Video orientation. Auto-detected from the prompt if omitted.                                                                        |
| `avatar`         | string     | optional | Any                     | Avatar to use in the video. Set to 'auto' to let the agent auto-select based on the prompt.                                         |
| `file_urls`      | file\_list | optional | Any                     | URLs of files to include as assets in the video (images, videos, audio, PDFs). Maximum 20 files.                                    |
| `incognito_mode` | boolean    | optional | Any                     | When enabled, disables the agent's memory functions.                                                                                |
| `style_id`       | string     | optional | Any                     | Style template ID from the /v3/video-agent/styles endpoint.                                                                         |
| `voice`          | string     | optional | Any                     | Voice for narration. Set to 'auto' to let the agent auto-select.                                                                    |

## Output schema

| Field           | Type | Description                        |
| --------------- | ---- | ---------------------------------- |
| `outputs`       | json | Unified output array.              |
| `seed`          | json | Seed used for generation, or null. |
| `timing`        | json | Provider timing info, or null.     |
| `nsfw_detected` | json | NSFW flag, or null.                |

## Callback payload

When you provide a `callback_url`, Runflow POSTs to it once the run reaches a terminal state.

| Field          | Type           | Description                                                    |
| -------------- | -------------- | -------------------------------------------------------------- |
| `event`        | string         | Event type: "run.completed", "run.failed", or "run.cancelled". |
| `run_id`       | string         | The unique identifier of the run.                              |
| `status`       | string         | Terminal status: "succeeded", "failed", or "cancelled".        |
| `output`       | object \| null | The run output. Null if the run failed or was cancelled.       |
| `duration_ms`  | number \| null | Total run duration in milliseconds.                            |
| `created_at`   | string \| null | ISO 8601 timestamp when the run was created.                   |
| `completed_at` | string \| null | ISO 8601 timestamp when the run reached terminal state.        |
| `metadata`     | object \| null | The metadata object passed at run creation, if any.            |

* **Retries:** 3 attempts with exponential backoff (1s, 2s). Retries on 5xx / network errors only.
* **Headers:** `Runflow-Request-Id` is always sent. `Runflow-Signature` is sent if a signing secret is configured.

## Additional Resources

* [Playground](https://app.runflow.io/models/heygen/v3/video-agent)
* [API Reference](https://app.runflow.io/models/heygen/v3/video-agent?tab=api)
* [Documentation](https://docs.runflow.io)
* [OpenAPI](https://docs.runflow.io/api/openapi.public.json)

## Related

<CardGroup cols={2}>
  <Card title="Browse all models" icon="grid" href="/models">Browse the catalog.</Card>
  <Card title="Run lifecycle" icon="play" href="/concepts/runs">Callbacks, polling, statuses.</Card>
  <Card title="Callbacks" icon="webhook" href="/concepts/callbacks">Handle async results.</Card>
  <Card title="Pricing" icon="coin" href="/concepts/pricing">How requests bill out.</Card>
</CardGroup>