maxgent-ai Media Processing
Process audio and video files using ffmpeg. Claude already knows ffmpeg well — this skill only defines the interaction flow.
Usage
When the user wants to process audio/video files: $ARGUMENTS
Instructions
Step 0: Choose interaction mode
On first interaction, use AskUserQuestion:
- Question: "Are you familiar with video processing?"
- Options:
- "Simple mode — just pick the best options for me (Recommended)"
- "Pro mode — I want full control over parameters"
If the user uses technical terms (CRF, codec, bitrate, etc.) in simple mode, automatically switch to pro mode.
Step 1: Analyze input files
Run ffprobe to inspect each input file:
ffprobe -v error -show_entries format=duration,size,bit_rate -show_entries stream=codec_name,codec_type,width,height,r_frame_rate,sample_rate,channels,bit_rate -of json "$INPUT_FILE"
Simple mode: show duration, resolution, file size. Pro mode: show full codec, bitrate, sample rate, and other technical details.
Step 2: Confirm key parameters before executing
You MUST use AskUserQuestion to confirm key parameters before running any ffmpeg command. Only ask questions relevant to the operation.
Simple mode — describe effects, not parameters
Trim example:
- "Where should it start? Where should it end?"
- "Output quality?" → "Same as original (fastest)" / "Slightly compressed (smaller file)" / "More compressed (much smaller)"
- "Keep the audio?" → "Yes" / "No"
Merge example:
- Show file list, confirm concatenation order
- "These files have different resolutions — which size should the output use?"
Extract audio example:
- "Output format?" → "MP3 (universal)" / "WAV (lossless)" / "AAC (high quality, small size)"
Pro mode — expose technical parameters
- Show codec, CRF, preset, bitrate options
- Allow custom parameter input
- For merging: offer concat demuxer vs concat filter choice
Extra checks for merging
When merging multiple files, you must:
- Check whether all files share the same resolution, codec, and audio codec
- If they differ, inform the user and ask how to handle it
- Confirm concatenation order
Step 3: Execute
- Build the ffmpeg command
- In pro mode, show the full command before running
- Execute and report progress
Step 4: Verify output
Run ffprobe on the output file and report:
Simple mode:
Done!
- Duration: 2m 30s
- File size: 45 MB (60% smaller than original)
- Saved to: /path/to/output.mp4
Pro mode:
Done!
- Output: 1920x1080, H.264 CRF 23, AAC 128kbps
- Duration: 2:30 | Size: 45.2 MB (was 112 MB, -60%)
- Path: /path/to/output.mp4
- Command: ffmpeg -ss 00:01:30 -to 00:04:00 -i input.mp4 ...
Key Principles
- Don't be an ffmpeg manual — Claude already knows ffmpeg; don't enumerate parameters
- Only ask what's needed — tailor questions to the specific operation, don't ask a long checklist every time
- Output path — default to current working directory, with an operation suffix (e.g.
_trimmed,_merged) - Error handling — if ffmpeg fails, explain the cause in plain language and suggest a fix