npx ffmpeg-skill
Left half is the input, right half is what the command produced. Every before/after demo, with the exact command under each one → — all of it built by python3 demos/build.py, so you can rebuild every frame of it yourself. The footage is synthetic (FFmpeg's own test sources) except in three demos, reframe_talk, filler_en and pauses_en, which use two AI-generated clips of people who do not exist (demos/footage/).
ffmpeg-skill is an Agent Skill for Claude Code, Cursor, Codex and any agent that reads SKILL.md. It teaches the agent a fixed workflow (probe → edit losslessly where possible → check → verify) and ships 42 tools that do the actual work with ffmpeg / ffprobe: cut, join, silence removal, fit to duration and aspect, captions and karaoke, overlays and motion graphics, HDR → SDR and LUTs, audio clean-up and typed dynamics, sync with drift correction, multicam, loudness, delivery checks, whole-edit project rendering, batch folders. Every tool is also callable as an MCP tool (tools/list advertises a core 12 by default to keep client context small, with FFMPEG_SKILL_MCP_FULL=1 listing all 42; every tool is reachable by name through tools/call either way), and the whole set is described by a machine-readable contract.
If ffmpeg and python3 are on your PATH, it works: offline, on footage you would rather not upload.
SPEC (Self-Producing Execution Contract): each tool's input_schema — the part of its
contract and MCP tool definition that has to track the CLI flag-for-flag — is never
hand-authored beside the code. It is derived, at run time, from the same argparse parser that
already defines the CLI, and CI fails the build if any of it drifts.
→ full explanation
Standalone, and in an ecosystem
Standalone, this is a local FFmpeg engine: probe → edit → verify, npx ffmpeg-skill and nothing else. No API key, no account, no other repo required. Everything above and below this section describes that standalone tool, and none of it changes if you never read the rest of this one.
In kajisho5's wider video-production ecosystem, this repo is the hands: it cuts, measures and exports files, and reports back in structured JSON. It does not decide what to cut, whether a deliverable is approvable, what makes a highlight interesting, or what a caption should say (the user's cue text is burned as written, never rewritten to fit) — those are a brain's job, sitting in front of this engine, not inside it.
| You want to... | Use |
|---|
| Cut / join / measure / export a file right now | this repo (ffmpeg-skill), standalone |
| Decide cut points, approve a deliverable, plan a whole edit | video-production-agent / AI-video-production-OS |
Build a typed editing graph across a workspace, without writing raw ffmpeg | video-editing-skill / audio-production-skill |
| Put Remotion motion graphics (animated captions, silence jump cuts, audio-peak motion) on a real recording | remotion-ffmpeg-skill: its compositions take their length, fps, frame, silences, scene cuts, audio peaks and beats from this repo's probe.py, silence.py and scenes.py. It verifies its render with check.py and look.py, composites a graphics layer with overlay.py (--place for its --sparse mode), and delivers through render.py --template |
Other repos in the ecosystem — media-analysis-skill, transcription-skill, subtitle-skill, thumbnail-skill, color-grading-skill, motion-graphics-skill, qc-skill — read this repo's contract --json, its tools' --json output and doctor, the same way any agent framework would; this repo does not call into any of them. The dependency runs one way.
Contents
Standalone, and in an ecosystem · Why · Quick start · How it works · Design principles · Tools · Audio · Built for agents · FAQ · FFmpeg compatibility · Tested on real footage · Install · Requirements · Development · Docs
Why
An agent that "knows FFmpeg" still guesses: it assumes a frame rate, picks a codec the container cannot hold, re-encodes a file that only needed a stream copy, and reports "done" without opening the result. This skill takes the guessing out:
This is the beginning of the README. Read the rest at the original. Read the full README ↗
