runwayml/rw-generate-video

Generate Video

Generate videos directly using the Runway API. This skill runs Python scripts that call the API, poll for completion, and download the result.

IMPORTANT: Run scripts from the user's working directory so output files are saved where the user expects.

Usage

uv run scripts/generate_video.py --prompt "your description" --filename "output.mp4" [--model seedance2] [--ratio 1280:720] [--duration 5] [--image-url "..."] [--api-key KEY]

Preflight

1. command -v uv must succeed. If not, tell the user to install uv: curl -LsSf https://astral.sh/uv/install.sh | sh
2. RUNWAYML_API_SECRET must be set, or the user passes --api-key

Available Models

| Model | Best For | Input | Cost | |-------|----------|-------|------| | seedance2 | Reference image and video, long duration (up to 15s) | Text, Image, and/or Video | 36 credits/sec | | gen4.5 | High quality, general purpose | Text and/or Image | 12 credits/sec | | gen4_turbo | Fast, image-driven | Image required | 5 credits/sec | | gen4_aleph | Video editing/transformation | Video + Text/Image | 15 credits/sec | | veo3 | Premium quality | Text/Image | 40 credits/sec | | veo3.1 | High quality Google model | Text/Image | 20-40 credits/sec | | veo3.1_fast | Fast Google model | Text/Image | 10-15 credits/sec |

Model Selection Guidance

Map user requests:

• "product ad", "e-commerce", "long video" -> seedance2
• "fast", "cheap", "quick" -> veo3.1_fast or gen4_turbo (if they have an image)
• "high quality", "best", "cinematic" -> gen4.5 or veo3
• "edit video", "transform video" -> gen4_aleph or seedance2
• No preference -> seedance2

Parameters

| Param | Description | Default | |-------|-------------|---------| | --prompt | Text description (required) | -- | | --filename | Output filename (required) | -- | | --model | Video model | gen4.5 | | --ratio | Aspect ratio (pixel-based). Common: 1280:720, 720:1280, 960:960. seedance2 also supports 1112:834, 834:1112, 1470:630, etc. | 1280:720 | | --duration | Duration in seconds (model-dependent, seedance2 supports up to 15s) | 5 | | --image-url | Image URL or local file for image-to-video | -- | | --video-url | Video URL or local file for video-to-video (gen4_aleph, seedance2) | -- | | --output-dir | Output directory | cwd | | --api-key | Runway API key | env RUNWAYML_API_SECRET |

Filename Convention

Generate filenames with the pattern: yyyy-mm-dd-hh-mm-ss-name.mp4

Examples:

• "A cyberpunk city" -> 2026-04-14-14-23-05-cyberpunk-city.mp4
• "Waves on a beach" -> 2026-04-14-15-30-12-beach-waves.mp4

Examples

Text-to-video (seedance2):

uv run scripts/generate_video.py --prompt "A serene mountain landscape at sunrise with mist" --filename "2026-04-14-mountain-sunrise.mp4" --model seedance2 --ratio 1280:720

Image-to-video (animate a product photo):

uv run scripts/generate_video.py --prompt "Camera slowly zooms out, product sparkles" --image-url "product.jpg" --filename "2026-04-14-product-reveal.mp4" --model seedance2 --ratio 720:1280

Video-to-video (seedance2):

uv run scripts/generate_video.py --prompt "Transform into a warm golden sunset scene" --video-url "input.mp4" --filename "2026-04-14-sunset-transform.mp4" --model seedance2

Fast draft:

uv run scripts/generate_video.py --prompt "A cat playing piano" --filename "draft.mp4" --model veo3.1_fast --ratio 1280:720 --duration 4

Premium quality:

uv run scripts/generate_video.py --prompt "Cinematic drone shot over Tokyo at night" --filename "tokyo.mp4" --model veo3 --ratio 1280:720 --duration 8

Output

• The script downloads the result and saves it to the specified path
• Script outputs the full path to the saved file
• Do not read the video file back -- just inform the user of the saved path

Common Failures

• Error: No API key -> set RUNWAYML_API_SECRET or pass --api-key
• Error: Task failed -- SAFETY.INPUT.* -> content moderation, suggest different prompt
• Error: Task failed -- ASSET.INVALID -> bad input file format, check image/video format
• API error 429 -> rate limited, script auto-retries

For Batch Generation

To generate many videos at once, run this script in a loop — the agent can orchestrate multiple calls with different prompts, images, or parameters to produce campaigns, localized variants, or creative iterations at scale.