The app

Working with an AI assistant (MCP)

JOS Compositor has a built-in MCP server, the protocol AI assistants use to work with applications. Claude, or any other MCP client, can work in the comp you have open:

create and connect nodes;
set parameters, expressions and keyframes;
render, and read pixel values and statistics;
track, import and export.

The AI's edits appear in the graph straight away and go on your undo stack: Ctrl+Z undoes them like your own.

Turning it on

Go to Edit > Preferences > AI assistants:

Let AI assistants edit the open project (on this computer only) is on by default.
Port is 8756.

The server only answers on this computer (http://127.0.0.1:8756/mcp).

Connecting Claude

Claude Code: press Copy Claude Code command and run the copied command once in a terminal.
Claude Desktop: press Copy Claude Desktop config and paste the entry into Claude Desktop's claude_desktop_config.json, under mcpServers. It runs jos-mcp.exe --app (with the port after it when you changed it), which connects Claude Desktop to the running JOS.
Without the app: jos-mcp comp.joscomp runs the server on its own, with no window, for scripted or batch work.

What the AI can do

Area	Tools
Graph	list node types and colour spaces, read the graph or a node, create, delete, connect, disconnect, rename, disable, clone and link nodes
Settings	set parameters and expressions, set and remove keys, curves (loop, bounce, noise)
Rendering	render a node and get channel statistics, pixel samples or a file; execute a Write
Project	new, open, save, project settings (including the colour config), undo, redo
Tracking	add tracks, track, export, fill gaps, solve a hidden corner
Nests	create a Nest, nest nodes, expose a parameter; every tool can work inside a Nest
Import and export	Nuke scripts, SVG files

Every change goes through the same checks and undo as your own edits. The AI can't do anything to the comp that you couldn't undo.

Not yet

Copy and paste.
Deleting a node with reconnection.
Drawing a tracker's occlusion shapes.