video-gen（视频生成器）

Video Generator

Generate videos via Maxgent FAL API proxy. Supports text-to-video, image-to-video, and first/last frame mode.

Prerequisites

1. MAX_API_KEY environment variable (auto-injected by Max)
2. Python 3.10+ (supports uv run or python3)

Routing

1. Default auto-routing (high quality)

- Text-to-video: fal-ai/veo3.1 - Image-to-video: fal-ai/sora-2/image-to-video/pro

1. Optional explicit models

- veo-3.1 - sora-2-pro - kling-v3-pro - kling-v3-standard

First/last frame default routing:

1. fal-ai/veo3.1/first-last-frame-to-video
2. With --fast-first-last: fal-ai/veo3.1/fast/first-last-frame-to-video

Usage

uv run skills/video-gen/video-gen.py \
  --model MODEL --prompt "PROMPT" --size SIZE --seconds N \
  --output-dir DIR \
  [--start-image PATH] [--end-image PATH] \
  [--frame-mode auto|start|start-end] [--fast-first-last] \
  [--generate-audio true|false] [--enhance-prompt true|false] \
  [--negative-prompt TEXT] [--cfg-scale N]

Parameters:

• --model: auto (recommended), veo-3.1, sora-2-pro, kling-v3-pro, kling-v3-standard
• --prompt: video description
• --size: 720P, 1080P, 1280x720, 720x1280
• --seconds: duration, e.g. 8 or 8s
• --output-dir: output directory — default to $MAX_PROJECT_PATH (the user's project root)
• --start-image: start frame image path or URL (for image-to-video)
• --end-image: end frame image path or URL (for first/last frame mode)
• --frame-mode: auto (default), start, start-end
• --fast-first-last: use Veo fast first/last frame route
• --generate-audio: enable audio generation (default true)
• --enhance-prompt: enable prompt enhancement (default true)
• --negative-prompt: negative prompt (Kling only)
• --cfg-scale: CFG scale (Kling only)

Examples

# Text-to-video (default routing)
uv run skills/video-gen/video-gen.py --model auto --prompt "a golden retriever running on the beach, camera follows" --size 720P --seconds 8 --output-dir "$MAX_PROJECT_PATH"

# Image-to-video (Sora Pro)
uv run skills/video-gen/video-gen.py --model sora-2-pro --prompt "make the person smile and wave" --size 1280x720 --seconds 8 --output-dir "$MAX_PROJECT_PATH" --start-image "/path/to/start.jpg"

# First/last frame (Veo)
uv run skills/video-gen/video-gen.py --model auto --prompt "smooth transition from winter to spring" --size 1080P --seconds 8 --output-dir "$MAX_PROJECT_PATH" \
  --start-image "/path/to/start.jpg" \
  --end-image "/path/to/end.jpg" \
  --frame-mode start-end

Instructions

1. Check MAX_API_KEY.
2. Use AskUserQuestion to collect: prompt, duration, resolution, first/last frame option, quality tier. Default output path to $MAX_PROJECT_PATH.
3. For local images, the script auto-uploads via proxy to get an accessible URL.
4. Wait for queue completion and download the output mp4.
5. On success, report the saved path.
6. On failure:

- HTTP 402 (insufficient credits): Stop immediately. Do NOT retry. Tell the user their API credits are exhausted. - Other errors: retry once with a different model or adjusted parameters. If it fails again, stop and report the error.