mcpCut
A real video editor for AI agents, served over MCP.
mcpCut gives any MCP-capable agent (Claude Code, Claude Desktop, or anything else that speaks the protocol) an actual editing model — not a wrapper around one ffmpeg command. Projects are immutable snapshots with a journaled history of named operations; rendering goes through FFmpeg or the MLT framework; a deterministic CLI twin drives the same logic without a server.
Two ways to use it
☁️ Hosted (fastest — no install). mcpcut.com runs this editor as a service, with a browser editor on top: sign up, create an API token, and point your agent at the cloud MCP endpoint:
claude mcp add --transport http mcpcut https://mcpcut.com/mcp \
--header "Authorization: Bearer <your token>"
You and your agent then work on the same projects — the agent edits over MCP, you review and tweak in the browser editor.
🖥 Self-hosted (this repository). The open, single-user core: run it on your own machine, point your agent at it, keep everything local. No accounts, no browser editor — just the MCP server, the editing engine and the CLI. The rest of this README is about this option.
What the agent gets
44 tools over one consistent model:
- Projects & history — create/list projects, journaled operations
(
editor_get_historyshows every edit ever made), named versions with restore, annotations. - Timeline — multiple video/audio tracks, clips with trim/split/move/ resize, transforms with keyframes, transitions, canvas fit, color adjustments.
- Text & graphics — text overlays rasterized server-side, image/video overlays, covers.
- Audio — music beds, per-clip audio, volume envelopes.
- Media in — local paths or URLs (URL import goes through an SSRF egress guard; media is sanity-checked with ffprobe before it touches a timeline).
- Understanding — media analysis (scenes, audio peaks, keyframes),
auto-captions via faster-whisper (
.[asr]extra), local voiceover via piper (.[tts]extra, GPL — see THIRD_PARTY_NOTICES.md). - Out — validation, preview renders, full exports with presets. Each
export writes an
.mltsidecar you can open in Shotcut or Kdenlive.
Every mutation validates its arguments against the tool's real signature (strings can't leak into numeric filter fields), returns a fresh snapshot with a bumped version, and lands in the journal. Nothing edits in place.
Prerequisites
- Python 3.12+
- FFmpeg (
ffmpeg+ffprobeon PATH) - MLT (
melton PATH) — the default render engine. Alternatively setRENDER_ENGINE=ffmpegand skip melt. - A font for text rendering, e.g. Debian/Ubuntu:
apt install fonts-dejavu-core fonts-noto-color-emoji(elsewhere, pointFONT_PATHat any.ttf).
# Debian/Ubuntu, everything at once:
apt install ffmpeg melt fonts-dejavu-core fonts-noto-color-emoji
Quickstart
git clone https://github.com/musyta-labs/mcpCut && cd mcpCut
python3 -m venv .venv && .venv/bin/pip install -e .
cp .env.example .env # MCP_AUTH_ENABLED=false is already set there
.venv/bin/python -m app.mcp.server
The server starts on http://127.0.0.1:8100 — the MCP endpoint is
http://127.0.0.1:8100/mcp. The database (SQLite) and media workspace are
created on first run.
Or with Docker (ffmpeg, melt and fonts included in the image):
docker build -t mcpcut .
docker run -p 127.0.0.1:8100:8100 -e MCP_TRANSPORT=streamable-http \
-v mcpcut-data:/data mcpcut
Single-user by design. This build has no accounts: whoever can reach the port is the operator, with full tool access including local file paths. Keep it bound to localhost, or put an authenticating reverse proxy in front.
MCP_AUTH_ENABLED=falsemust be set explicitly — the server refuses to start otherwise, so an open port is always a decision you made.
Connect an agent
Claude Code:
claude mcp add --transport http mcpcut http://127.0.0.1:8100/mcp
Any other MCP client, in its JSON config:
{
"mcpServers": {
"mcpcut": { "type": "http", "url": "http://127.0.0.1:8100/mcp" }
}
}
Then ask the agent for something real: “make a 30-second cut of
~/videos/talk.mp4 with auto-captions and export it.” The skills/ directory
contains ready-made instructions you can hand to any agent — see
skills/README.md.
Or drive it without a server
The CLI twin runs the same operations deterministically:
echo '{"op": "create_project", "args": {"metadata": {}}}' > /tmp/ops.json
.venv/bin/python -m app.mcp.cli /tmp/ops.json
Configuration
Everything lives in environment variables (or .env); see
.env.example for the full annotated list. The ones that
matter most:
| Variable | Default | What it does |
|---|---|---|
MCP_AUTH_ENABLED | true | must be set to false in this build (see above) |
DATABASE_URL | sqlite:///./data/editor.db | SQLite by default; Postgres via .[postgres] |
MEDIA_DIR | ./media | originals, exports, previews, caches |
MCP_HOST / MCP_PORT | 0.0.0.0 / 8100 | bind address of the server |
RENDER_ENGINE | mlt | mlt or ffmpeg |
FONT_PATH | DejaVu Bold (Debian path) | font for text overlays and captions |
EXPORT_TTL_HOURS / CLIP_CACHE_TTL_HOURS | 24 / 48 | retention sweep; RETENTION_ENABLED=false disables it |
Retention is real: a background daemon deletes exports after 24 h and
cached clips after 48 h by default. On a personal machine either download
your exports promptly or set RETENTION_ENABLED=false.
How it's built
| Layer | Where | What |
|---|---|---|
| Timeline model | app/editor/model.py | frozen dataclasses; every edit returns a new project, version + 1 |
| Mutations | app/editor/mutations.py | pure functions, one named journaled operation per gesture |
| Validation | app/editor/validation.py | structural checks + opt-in shorts profile |
| Render | app/editor/render.py | one contract, two engines: mlt_graph.py (default) and ffmpeg_graph.py |
| Analysis | app/analysis/ | scenes, peaks, keyframes — feeds the agent's decisions |
| Storage | app/db/ | SQLite/Postgres via SQLAlchemy + Alembic; append-only operation journal |
| MCP server | app/mcp/server.py | streamable-http or stdio; tool schemas derived from real signatures |
| CLI twin | app/mcp/cli.py | same operations, no server, deterministic |
Safety properties the codebase holds everywhere: no shell=True (argv lists
only), timeouts on every subprocess, atomic export writes, SSRF egress guard
on URL imports, argument validation derived from tool signatures.
License
MIT. Third-party obligations (FFmpeg/MLT installed by you, the
GPL piper-tts extra, fonts) are documented in
THIRD_PARTY_NOTICES.md.