Video Generation (Multi-Gateway)

Generate AI videos from text prompts. Supports multiple providers via two API gateways:

FAL_KEY

seedance_video

kling_video

minimax_video

veo_video

HEYGEN_API_KEY

heygen_video

Preferred premium default — Seedance 2.0. When any premium gateway is configured (

FAL_KEY

seedance_video

seedance-2-0

IMPORTANT: Always use

video_selector

Authentication

Use whichever configured gateway best matches the user's available providers and cost/quality goals.

• HeyGen: Set

  HEYGEN_API_KEY

  to access the multi-model gateway.
• fal.ai: Set

  FAL_KEY

  to access Kling, MiniMax, and Veo through fal.ai.

Do not describe either gateway as the default or top choice without checking the registry and current task fit first.

curl -X POST "https://api.heygen.com/v1/workflows/executions" \
  -H "X-Api-Key: $HEYGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"workflow_type": "GenerateVideoNode", "input": {"prompt": "A drone shot flying over a coastal city at sunset"}}'

Default Workflow

1. Call

   POST /v1/workflows/executions

   with

   workflow_type: "GenerateVideoNode"

   and your prompt
2. Receive a

   execution_id

   in the response
3. Poll

   GET /v1/workflows/executions/{id}

   every 10 seconds until status is

   completed

4. Use the returned

   video_url

   from the output

Execute Video Generation

Endpoint

POST https://api.heygen.com/v1/workflows/executions

Request Fields

workflow_type

"GenerateVideoNode"

input.prompt

input.provider

"veo_3_1"

input.aspect_ratio

"16:9"

"16:9"

"9:16"

"1:1"

input.reference_image_url

input.tail_image_url

input.config

Providers

"veo_3_1"

"veo_3_1_fast"

"veo3"

"veo3_fast"

"veo2"

"kling_pro"

"kling_v2"

"sora_v2"

"sora_v2_pro"

"runway_gen4"

"seedance_lite"

"seedance_pro"

"ltx_distilled"

curl

curl -X POST "https://api.heygen.com/v1/workflows/executions" \
  -H "X-Api-Key: $HEYGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "workflow_type": "GenerateVideoNode",
    "input": {
      "prompt": "A drone shot flying over a coastal city at golden hour, cinematic lighting",
      "provider": "veo_3_1",
      "aspect_ratio": "16:9"
    }
  }'

TypeScript

interface GenerateVideoInput {
  prompt: string;
  provider?: string;
  aspect_ratio?: string;
  reference_image_url?: string;
  tail_image_url?: string;
  config?: Record<string, any>;
}

interface ExecuteResponse {
  data: {
    execution_id: string;
    status: "submitted";
  };
}

async function generateVideo(input: GenerateVideoInput): Promise<string> {
  const response = await fetch("https://api.heygen.com/v1/workflows/executions", {
    method: "POST",
    headers: {
      "X-Api-Key": process.env.HEYGEN_API_KEY!,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      workflow_type: "GenerateVideoNode",
      input,
    }),
  });

  const json: ExecuteResponse = await response.json();
  return json.data.execution_id;
}

Python

import requests
import os

def generate_video(
    prompt: str,
    provider: str = "veo_3_1",
    aspect_ratio: str = "16:9",
    reference_image_url: str | None = None,
    tail_image_url: str | None = None,
) -> str:
    payload = {
        "workflow_type": "GenerateVideoNode",
        "input": {
            "prompt": prompt,
            "provider": provider,
            "aspect_ratio": aspect_ratio,
        },
    }

    if reference_image_url:
        payload["input"]["reference_image_url"] = reference_image_url
    if tail_image_url:
        payload["input"]["tail_image_url"] = tail_image_url

    response = requests.post(
        "https://api.heygen.com/v1/workflows/executions",
        headers={
            "X-Api-Key": os.environ["HEYGEN_API_KEY"],
            "Content-Type": "application/json",
        },
        json=payload,
    )

    data = response.json()
    return data["data"]["execution_id"]

Response Format

{
  "data": {
    "execution_id": "node-gw-v1d2e3o4",
    "status": "submitted"
  }
}

Check Status

Endpoint

GET https://api.heygen.com/v1/workflows/executions/{execution_id}

curl

curl -X GET "https://api.heygen.com/v1/workflows/executions/node-gw-v1d2e3o4" \
  -H "X-Api-Key: $HEYGEN_API_KEY"

Response Format (Completed)

{
  "data": {
    "execution_id": "node-gw-v1d2e3o4",
    "status": "completed",
    "output": {
      "video": {
        "video_url": "https://resource.heygen.ai/generated/video.mp4",
        "video_id": "abc123"
      },
      "asset_id": "asset-xyz789"
    }
  }
}

Polling for Completion

async function generateVideoAndWait(
  input: GenerateVideoInput,
  maxWaitMs = 600000,
  pollIntervalMs = 10000
): Promise<{ video_url: string; video_id: string; asset_id: string }> {
  const executionId = await generateVideo(input);
  console.log(`Submitted video generation: ${executionId}`);

  const startTime = Date.now();
  while (Date.now() - startTime < maxWaitMs) {
    const response = await fetch(
      `https://api.heygen.com/v1/workflows/executions/${executionId}`,
      { headers: { "X-Api-Key": process.env.HEYGEN_API_KEY! } }
    );
    const { data } = await response.json();

    switch (data.status) {
      case "completed":
        return {
          video_url: data.output.video.video_url,
          video_id: data.output.video.video_id,
          asset_id: data.output.asset_id,
        };
      case "failed":
        throw new Error(data.error?.message || "Video generation failed");
      case "not_found":
        throw new Error("Workflow not found");
      default:
        await new Promise((r) => setTimeout(r, pollIntervalMs));
    }
  }

  throw new Error("Video generation timed out");
}

Usage Examples

Simple Text-to-Video

curl -X POST "https://api.heygen.com/v1/workflows/executions" \
  -H "X-Api-Key: $HEYGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "workflow_type": "GenerateVideoNode",
    "input": {
      "prompt": "A person walking through a sunlit park, shallow depth of field"
    }
  }'

Image-to-Video

{
  "workflow_type": "GenerateVideoNode",
  "input": {
    "prompt": "Animate this product photo with a slow zoom and soft particle effects",
    "reference_image_url": "https://example.com/product-photo.png",
    "provider": "kling_pro"
  }
}

Vertical Format for Social Media

{
  "workflow_type": "GenerateVideoNode",
  "input": {
    "prompt": "A trendy coffee shop interior, camera slowly panning across the counter",
    "aspect_ratio": "9:16",
    "provider": "veo_3_1"
  }
}

Fast Generation with LTX

{
  "workflow_type": "GenerateVideoNode",
  "input": {
    "prompt": "Abstract colorful shapes morphing and flowing",
    "provider": "ltx_distilled"
  }
}

Best Practices

1. Be descriptive in prompts — include camera movement, lighting, style, and mood details
2. Default to Seedance 2.0 (via

   seedance_video

   ) for cinematic and motion-led work when

   FAL_KEY

   is set — single-pass synced audio, multi-shot, lip-sync, director-level camera. Use VEO 3.1 / Sora V2 Pro when the user specifically wants Google or OpenAI motion character; use

   ltx_distilled

   or

   veo3_fast

   only when speed is the hard constraint
3. Use reference images for image-to-video generation — great for animating product photos or still images
4. Video generation is the slowest workflow — allow up to 5 minutes, poll every 10 seconds
5. Aspect ratio matters — use

   9:16

   for social media stories/reels,

   16:9

   for landscape,

   1:1

   for square
6. Output includes

   asset_id

   — use this to reference the generated video in other HeyGen workflows
7. Output URLs are temporary — download or save generated videos promptly