delneg Qwen 3.5 Plus Video Feedback
Overview
Analyze videos with OpenRouter using the qwen/qwen3.5-plus-02-15 model. Designed as the feedback loop for Veo 3.1 video generation — pass a generated video and a prompt to get structured analysis and quality feedback.
Analyze a public video URL
uv run {baseDir}/scripts/analyze_video.py \
--video-url "https://example.com/generated.mp4" \
--prompt "Does this video match the description: a cat jumping over a fence? Rate quality 1-10."
Analyze a local video file (auto-uploaded to S3)
uv run {baseDir}/scripts/analyze_video.py \
--video-file /path/to/video.mp4 \
--prompt "Describe what is happening in this video and assess its overall visual quality."
Save analysis to a file
uv run {baseDir}/scripts/analyze_video.py \
--video-url "https://example.com/clip.mp4" \
--prompt "Evaluate prompt adherence and suggest improvements." \
--output feedback.txt
Arguments
| Argument | Required | Description |
|---|---|---|
--prompt |
Yes | Question or instruction for the model |
--video-url |
One of these | Public or presigned URL to the video |
--video-file |
One of these | Path to a local video file (uploaded to S3, then analyzed via presigned URL) |
--output |
No | File path to save the analysis text |
--video-url and --video-file are mutually exclusive.
S3 Configuration (required for --video-file)
Local files are uploaded to an S3-compatible bucket and accessed via a presigned URL (valid 1 hour). Set these environment variables:
| Variable | Required | Description |
|---|---|---|
S3_ENDPOINT_URL |
Yes | e.g. https://s3.us-east-1.amazonaws.com or https://nyc3.digitaloceanspaces.com |
S3_ACCESS_KEY_ID |
Yes | Access key ID |
S3_SECRET_ACCESS_KEY |
Yes | Secret access key |
S3_BUCKET |
Yes | Bucket name |
S3_REGION |
No | Region (default: us-east-1) |
S3_KEY_PREFIX |
No | Key prefix for uploads (default: video-analysis/) |
The bucket does not need to be public — presigned URLs are used.
Supported video formats
video/mp4, video/mpeg, video/mov, video/webm
System prompt customization
The skill reads an optional system prompt from assets/SYSTEM_TEMPLATE. Edit it to tune the model's feedback style (scoring rubric, artifact checklist, output format).
Behavior
- When
--video-fileis used: uploads the file to S3, generates a presigned URL, passes it to the model. Upload progress is printed to stderr. - Prints the full analysis to stdout.
- If
--outputis provided, also writes the text to that file and printsAnalysis saved to: <path>.
Chaining with veo3-1
VIDEO_URL=$(uv run veo3-1/scripts/generate_video.py --prompt "..." --url-only | grep '^VIDEO_URL:' | cut -d' ' -f2)
uv run {baseDir}/scripts/analyze_video.py \
--video-url "$VIDEO_URL" \
--prompt "Evaluate prompt adherence, list artifacts, rate 1-10."
Troubleshooting
| Symptom | Resolution |
|---|---|
OPENROUTER_API_KEY is not set |
export OPENROUTER_API_KEY="sk-or-..." |
S3_ENDPOINT_URL is not set |
Set S3 env vars (see S3 Configuration above) |
Video file not found |
Check the path passed to --video-file |
AuthenticationError / HTTP 401 |
Key invalid or out of credits. Check https://openrouter.ai/settings/keys. |
Missing Content-Length / upstream error |
The provider doesn't support base64 data URLs — use --video-file (S3 upload) or --video-url with a direct HTTP URL. |
uv: command not found |
macOS/Linux: curl -LsSf https://astral.sh/uv/install.sh | sh. Restart terminal. |
For transient errors (HTTP 429, network timeouts), retry once after 30 seconds. Do not retry the same error more than twice — surface it to the user instead.