Edit videos locally using ffmpeg. Trim, concat, resize, speed, overlay, extract audio, compress, and convert.
SkillScore82Maintained
Automatic
◆Marketing & Content pack
Last verified 8/17/2026
What it changes
Passed 18 of 22 test cases with the skill, and 7 of 22 without it.
Without skill32%
With skill82%
Checks it passed that the model alone missed
Includes the -y flag.
Includes the -y flag in the command.
Uses -acodec libmp3lame for MP3 encoding.
and 5 more in the full report
11 fixed7 passed either way4 still failing0 broke
Pass-rate lift
+50 pp
Tokens
+31%
Agent turns
0%
Response time
-42%
Model gemini-3.6-flashMeasured 8/17/2026v118 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 11 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 11
Prompt
I want to overlay watermark logo.png onto video.mp4 in the top-right corner with a 10-pixel offset from the top and right edges, preserving audio in watermarked.mp4. What is the filter string?
What was checked, without and with the skill
Checked
Without skill
With skill
Uses filter_complex with overlay=W-w-10:10.
Passed
Passed
Copies audio using -c:a copy.
Passed
Passed
Includes the -y flag.
Missed
Passed
case-11 · gemini-3.6-flash · 8/17/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md111 lines2 files
Video Edit
Edit videos locally by running ffmpeg/ffprobe directly. No wrapper scripts needed.