manifest.json Reference
The manifest.json at the repo root describes MCP for Unity as a package — independent of Unity's UPM package.json (which lives at MCPForUnity/package.json). It's used by MCP marketplaces and aggregators to surface the project's metadata, server invocation, and tool catalog.
If you're adding a new MCP tool, update the tool registry and let CI's drift check fail any stale entry — the generator keeps the docs in sync. The tools block in manifest.json is a separate, hand-maintained surface (see Notes below).
Top-level fields
| Field | Type | Description |
|---|---|---|
manifest_version | string | Schema version for this manifest (currently "0.3") |
name | string | Display name shown by aggregators |
version | string | Semver of the current release |
description | string | One-line product description |
author.name | string | Maintainer's display name |
author.url | string | Maintainer's website |
repository.type | string | "git" |
repository.url | string | Canonical repo URL |
homepage | string | Project homepage |
documentation | string | Docs landing URL |
support | string | Where to file issues |
icon | string | Path to a square icon, relative to the manifest |
server
Tells aggregators how to launch the Python server.
"server": {
"type": "python",
"entry_point": "Server/src/main.py",
"mcp_config": {
"command": "uvx",
"args": ["--from", "mcpforunityserver", "mcp-for-unity"],
"env": {}
}
}
type— runtime family. Currently always"python".entry_point— file an aggregator would point a Python interpreter at if it weren't usinguvx.mcp_config.command— recommended launch command.uvxkeeps the dependency tree managed without a global install.mcp_config.args— invocation arguments. Default transport ishttp; pass--transport stdioto switch.mcp_config.env— environment variables to set before launching (telemetry opt-outs, log levels, etc.).
tools
A flat array of { name, description } entries listing every MCP tool the server exposes. Aggregators use it for search and category surfaces without having to introspect the live registry.
This list is hand-maintained for now. The authoritative count and metadata live in the Python tool registry — see the Tool reference for the generated catalog with full parameter docs.
Notes
manifest.jsonis NOT the Unity UPM manifest. That'sMCPForUnity/package.json(name:com.coplaydev.unity-mcp).- The Python PyPI package metadata lives in
Server/pyproject.toml(name:mcpforunityserver). - All three —
manifest.json,package.json,pyproject.toml— are independent surfaces with overlapping but non-identical fields. A rename touches all three. - An MCPB bundle is produced from
manifest.jsonviatools/generate_mcpb.py.
Where it ships
The current manifest.json is at the repo root: manifest.json.