# Heygen Avatar API Documentation

> LLM-optimized documentation for Heygen Avatar. Copy into your AI assistant for integration help.

## Overview

**Model ID:** `heygen-avatar`
**Type:** Video Generation
**Credit Cost:** 120 credits per video

Heygen Avatar 4 via fal.ai — animate a portrait with prompt-driven speech or an audio track, with optional background and captions.

## Endpoint

```
POST https://pixeldojo.ai/api/v1/models/heygen-avatar/run
```

## Authentication

All requests require an API key in the Authorization header:

```
Authorization: Bearer YOUR_API_KEY
```

Get your API key: https://pixeldojo.ai/api-platform/api-keys

## Input Parameters

| Parameter | Type | Required | Default | Description |
|-----------|------|----------|---------|-------------|
| `image` | url | Yes | - | URL of the portrait image to animate |
| `prompt` | string | No | - | Text the avatar will speak. Required unless audio_url is provided. |
| `voice` | enum | No | Ivy | Name of the voice to use for the avatar. Ignored when audio_url is provided. (Options: Warm Pro Narrator, Chill Brian, Ivy, John Doe, Monika Sogam...) |
| `talking_style` | enum | No | stable | stable for minimal movement, expressive for animated motion (Options: stable, expressive) |
| `expressionHappy` | boolean | No | false | Set true to add a "happy" facial expression. (Currently the only supported expression.) |
| `backgroundType` | enum | No | none | Background source: "none" leaves the avatar background intact; "color"/"image"/"video" replaces it via backgroundValue. (Options: none, color, image, video) |
| `backgroundValue` | string | No | - | Hex color for type=color, URL for type=image/video. Ignored when type=none. |
| `audio_url` | url | No | - | URL of an audio file for lip-sync. When provided, overrides prompt and voice. |
| `resolution` | enum | No | 720p | Output resolution preset (Options: 360p, 480p, 540p, 720p, 1080p) |
| `aspect_ratio` | enum | No | 16:9 | Output video aspect ratio: 16:9 landscape, 9:16 portrait, or 1:1 square (Options: 16:9, 9:16, 1:1) |
| `caption` | boolean | No | false | Overlay generated captions on the output video |

## Supported Aspect Ratios

- `16:9`
- `9:16`
- `1:1`

## Capabilities

- Image to Video
- Audio Generation

## Quick Start

### 1. Submit a Job

```bash
curl -X POST "https://pixeldojo.ai/api/v1/models/heygen-avatar/run" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "A cinematic shot of ocean waves crashing at golden hour, 4K quality",
    "aspect_ratio": "16:9",
    "duration": 5
  }'
```

**Response:**
```json
{
  "jobId": "job_abc123...",
  "status": "pending",
  "statusUrl": "https://pixeldojo.ai/api/v1/jobs/job_abc123",
  "creditCost": 120,
  "creditsRemaining": 95
}
```

### 2. Poll for Results

```bash
curl "https://pixeldojo.ai/api/v1/jobs/job_abc123" \
  -H "Authorization: Bearer YOUR_API_KEY"
```

**Completed Response:**
```json
{
  "jobId": "job_abc123...",
  "status": "completed",
  "output": {
    "video": "https://temp.pixeldojo.ai/..."
  },
  "creditCost": 120
}
```

## Python Example

```python
import requests
import time

API_KEY = "YOUR_API_KEY"

# Submit job
response = requests.post(
    "https://pixeldojo.ai/api/v1/models/heygen-avatar/run",
    headers={
        "Authorization": f"Bearer {API_KEY}",
        "Content-Type": "application/json"
    },
    json={
        "prompt": "A cinematic shot of ocean waves crashing at golden hour, 4K quality",
        "aspect_ratio": "16:9",
        "duration": 5
    }
)

job = response.json()
job_id = job["jobId"]

# Poll for completion
while True:
    status_response = requests.get(
        f"https://pixeldojo.ai/api/v1/jobs/{'{job_id}'}",
        headers={"Authorization": f"Bearer {API_KEY}"}
    )
    status = status_response.json()
    
    if status["status"] == "completed":
        print("Output:", status["output"])
        break
    elif status["status"] == "failed":
        print("Error:", status.get("error"))
        break
    
    time.sleep(2)
```

## JavaScript Example

```javascript
const API_KEY = 'YOUR_API_KEY';

// Submit job
const submitResponse = await fetch('https://pixeldojo.ai/api/v1/models/heygen-avatar/run', {
  method: 'POST',
  headers: {
    'Authorization': `Bearer ${API_KEY}`,
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    prompt: 'A cinematic shot of ocean waves crashing at golden hour, 4K quality',
    aspect_ratio: '16:9',
    duration: 5
  })
});

const job = await submitResponse.json();

// Poll for completion
const pollForResult = async (jobId) => {
  while (true) {
    const statusResponse = await fetch(`https://pixeldojo.ai/api/v1/jobs/${jobId}`, {
      headers: { 'Authorization': `Bearer ${API_KEY}` }
    });
    const status = await statusResponse.json();
    
    if (status.status === 'completed') return status.output;
    if (status.status === 'failed') throw new Error(status.error);
    
    await new Promise(r => setTimeout(r, 2000));
  }
};

const output = await pollForResult(job.jobId);
console.log('Output:', output);
```

## Error Codes

| Code | Status | Description |
|------|--------|-------------|
| `unauthorized` | 401 | Invalid or missing API key |
| `insufficient_credits` | 402 | Not enough credits |
| `invalid_request` | 400 | Invalid parameters |
| `model_not_found` | 404 | Model ID not found |
| `rate_limited` | 429 | Too many requests |
| `internal_error` | 500 | Server error |

## Links

- **Full Documentation:** https://pixeldojo.ai/api-platform/heygen-avatar
- **API Keys:** https://pixeldojo.ai/api-platform/api-keys
- **Buy Credits:** https://pixeldojo.ai/api-platform/buy-credits
- **All Models:** https://pixeldojo.ai/api/v1/models
- **OpenAPI Spec:** https://pixeldojo.ai/api/openapi