Installation

Install Unity MCP (AI Game Developer) in a Unity project with the desktop app, unity-mcp-cli, OpenUPM or the .unitypackage installer.

Updated November 4, 2026 View as Markdown

This page shows every way to add the Unity MCP plugin to a Unity project, what each one does to your project, and how to remove the plugin again. All paths install the same package, com.ivanmurzak.unity.mcp, from the OpenUPM registry, so you can pick whichever fits your workflow.

Requirements

  • Unity 2022.3 or newer. The package declares 2022.3 as its minimum version; Unity 6 releases are supported.
  • A project path without spaces. C:/Projects/MyGame is fine, C:/My Projects/My Game is not. The plugin logs an error at startup when the path contains a space.
  • A short project path on Windows. The plugin copies its NuGet DLLs to Assets/Plugins/NuGet. If the resulting path would pass Windows' 260-character limit, the install stops and asks you to move the project to a shorter folder.
  • Internet access on first open. The plugin downloads its .NET dependencies from NuGet, and in Custom mode its MCP server binary from GitHub.
  • For unity-mcp-cli only: Node.js ^20.19.0 or >=22.12.0.

Option 1: the AI Game Dev desktop app (recommended)

The AI Game Dev app installs and connects the plugin for you, without a terminal and without Node.js on your machine.

  1. Download the app and sign in with your ai-game.dev account.
  2. Open your Unity project folder in the app. The app detects that it is a Unity project.
  3. Click Install Package. The app adds the plugin to Packages/manifest.json at the newest released version on OpenUPM, and never downgrades a newer version you already have. A project you create from the app gets the plugin automatically.
  4. Open the Editor from the app. The app passes your session, so the plugin connects through ai-game.dev without a separate sign-in.

The app also installs extensions and runs the AI agent itself, so you do not need a separate MCP client. Details are in the app wiki: installation and projects and engines.

Option 2: unity-mcp-cli

unity-mcp-cli edits Packages/manifest.json directly, so Unity does not need to be open:

npm install -g unity-mcp-cli
unity-mcp-cli install-plugin ./MyUnityProject

You can also run it without a global install:

npx unity-mcp-cli install-plugin ./MyUnityProject

install-plugin adds the OpenUPM scoped registry with the scopes com.ivanmurzak and extensions.unity, adds com.ivanmurzak.unity.mcp to dependencies at the latest OpenUPM version, and never downgrades a higher version that is already installed. Pass --plugin-version <version> to pin a version. The path is optional when you run the command from the project folder.

The CLI can also install Unity and create a project first:

unity-mcp-cli install-unity
unity-mcp-cli create-project ./MyUnityProject

If Unity Hub is missing, the CLI installs it. Open the project in Unity afterwards so the Package Manager resolves the package. All commands are in the CLI reference.

Option 3: OpenUPM

With the OpenUPM CLI installed, run this in the project folder:

openupm add com.ivanmurzak.unity.mcp

Without the OpenUPM CLI, add the registry and the dependency to Packages/manifest.json yourself. Use the version shown on the OpenUPM package page:

{
  "scopedRegistries": [
    {
      "name": "package.openupm.com",
      "url": "https://package.openupm.com",
      "scopes": ["com.ivanmurzak", "extensions.unity"]
    }
  ],
  "dependencies": {
    "com.ivanmurzak.unity.mcp": "1.6.2"
  }
}

Merge these entries into your existing file; do not replace the other dependencies.

Option 4: the .unitypackage installer

  1. Download AI-Game-Dev-Installer.unitypackage.
  2. Open your project in Unity.
  3. Double-click the file, or use Assets > Import Package > Custom Package and pick it.
  4. Click Import.

The installer is a small editor script. It adds the OpenUPM scoped registry and the plugin dependency to Packages/manifest.json, then deletes itself from Assets. The Package Manager then downloads the real package.

What happens on first open

After the package arrives, the plugin prepares itself:

  • It downloads the .NET libraries it needs (the MCP plugin library, ReflectorNet, RQL, SignalR, System.Text.Json and others) from NuGet into Assets/Plugins/NuGet, with a cache in Library/NuGetCache, and Unity recompiles once. If those DLLs ever get out of sync, use Tools > AI Game Developer > Dependencies > Force Resolve NuGet DLLs.
  • It downloads the gamedev-mcp-server binary for your platform from GitHub to Library/mcp-server/<platform>/ (for example win-x64, osx-arm64 or linux-x64). The server is started only in Custom mode with the HTTP transport; Cloud mode, the default, starts no local server.
  • The AI Game Developer window becomes available under Window > AI Game Developer — MCP (shortcut Ctrl+Alt+A, or Cmd+Option+A on macOS). The Scene View toolbar also gets an AI overlay button that opens it.

Library/ is excluded from version control by default, so the server binary is never committed. In CI environments the plugin skips the server download and start.

Updating the plugin

When a newer version is on OpenUPM, the plugin shows an update popup at Editor startup. You can check by hand with Tools > AI Game Developer > Updates > Check for Updates. To update, change the version in the Package Manager, re-run unity-mcp-cli install-plugin (it installs the latest), or let the desktop app update it.

For teams where one person owns the plugin version, open Edit > Project Settings > AI Game Developer and enable Disable update notifications for the entire team. The setting is saved in ProjectSettings/AI-Game-Developer-UpdateSettings.asset; commit that file. The same toggle is in Tools > AI Game Developer > Updates > Disable Update Notifications (Team).

Uninstalling

  1. Open Window > Package Manager, select AI Game Developer — MCP and click Remove, or run unity-mcp-cli remove-plugin ./MyUnityProject. The CLI keeps the scoped registry, because other packages may use it.
  2. Close Unity and delete the Assets/Plugins/NuGet folder and its Assets/Plugins/NuGet.meta file.

Next steps