Unity MCP Toolkit

A community-driven collection of custom MCP tools that extend Unity's official MCP integration. Each tool adds editor automation capabilities that AI coding agents can use to interact with the Unity Editor.

Tutorial

Learn how to build your own custom MCP tools for Unity from scratch. This video covers the [McpTool] attribute, parameter records with [McpDescription], and common pitfalls that prevent tools from showing up.

Watch the tutorial | Get the code

Requirements

• Unity 6+ (6000.0 or later)
• Unity AI Assistant (com.unity.ai.assistant 2.4.0-pre.1 or later) — this is a pre-release package

Optional Dependencies

• Input System (com.unity.inputsystem 1.0.0 or later) — required for Input System tools.
• Recorder (com.unity.recorder 5.0.0 or later) — required for Recorder tools.

Installation

Add the following to your project's Packages/manifest.json:

{
    "dependencies": {
        "com.whatupgames.unity-mcp-toolkit": "https://github.com/yecats/unity-mcp-toolkit.git"
    }
}

Or use Window > Package Manager > + > Add package from git URL and enter:

https://github.com/yecats/unity-mcp-toolkit.git

Tools

General

Tool	Type	Default	Description
McpToolkit.GetToolkitInfo	Read	On	Returns information about the Unity MCP Toolkit plugin, including version and a categorized list of all available tools with their enabled status. AI agents should call this first to discover toolkit capabilities.
McpToolkit.GameViewCapture	Read	On	Captures the Game View as a base64-encoded PNG. Supports a resolution multiplier (1-4x). Accounts for OS display scaling. Works in Edit and Play mode.
McpToolkit.ForceDomainRefresh	Action	On	Forces a domain reload even when the Unity Editor is not in the foreground. Use after modifying scripts externally to trigger recompilation without switching to Unity.

Project Settings

Tool	Type	Default	Description
McpToolkit.GetPlayerSettings	Read	On	Reads project identity, rendering, scripting configuration, and platform settings.
McpToolkit.SetPlayerSettings	Write	Off	Modifies player settings (company name, color space, scripting backend, defines, etc.).
McpToolkit.GetQualitySettings	Read	On	Reads all quality levels with shadow, AA, VSync, LOD, and rendering properties.
McpToolkit.SetQualitySettings	Write	Off	Modifies quality settings for a specific or active quality level.
McpToolkit.GetPhysicsSettings	Read	On	Reads 3D and 2D physics settings (gravity, solver iterations, queries, etc.).
McpToolkit.SetPhysicsSettings	Write	Off	Modifies 3D and 2D physics settings.
McpToolkit.GetTimeAndAudioSettings	Read	On	Reads time (fixed timestep, time scale) and audio (sample rate, voices) settings.
McpToolkit.SetTimeAndAudioSettings	Write	Off	Modifies time and audio settings.
McpToolkit.GetScriptExecutionOrder	Read	On	Reads scripts with custom execution order.
McpToolkit.SetScriptExecutionOrder	Write	Off	Sets execution order for a MonoScript by class name.

Build

Tool	Type	Default	Description
McpToolkit.GetBuildSettings	Read	On	Reads build target, development/debug/profiler flags, scenes in build, installed platforms, and compilation defines.
McpToolkit.SetBuildSettings	Write	Off	Toggles dev build, debugging, profiler flags. Manages scenes in build (add, remove, enable, disable, reorder). Excludes platform switching and build execution for safety.

Scene View

Tool	Type	Default	Description
McpToolkit.GetSceneViewCamera	Read	On	Reads Scene View camera pivot, rotation, zoom, projection, 2D mode, gizmos, lighting, grid, draw mode, and camera settings.
McpToolkit.SetSceneViewCamera	Write	Off	Modifies Scene View camera properties. Supports LookAt (world point) and FrameGameObject (frame by name) actions.

Input System

Requires com.unity.inputsystem 1.0.0+. Tools appear automatically when the package is installed.

Tool	Type	Default	Description
McpToolkit.GetInputActions	Read	On	Lists all Input Action Assets with action maps, actions, bindings, and control schemes. Supports summary or detailed view per asset.
McpToolkit.SetInputActions	Write	Off	Modifies Input Action Assets: add/remove action maps, actions, and bindings. Supports wholesale JSON replacement.

Recorder

Requires com.unity.recorder 5.0.0+. Tools appear automatically when the package is installed.

Tool	Type	Default	Description
McpToolkit.GetRecorderSettings	Read	On	Reads the Recorder configuration: session settings (frame rate, record mode, frame/time interval), all configured recorders with type-specific properties, and current recording state.
McpToolkit.SetRecorderSettings	Write	Off	Modifies Recorder configuration. Supports session-level settings and recorder list management: add, remove, enable, disable, or modify recorders (Movie, Image Sequence, Audio, Animation Clip).
McpToolkit.StartRecording	Action	Off	Starts a recording session using the current Recorder configuration. Automatically enters Play mode.
McpToolkit.StopRecording	Action	Off	Stops any active recording session. Output files are written when the recording stops.

Managing Tools

You can toggle individual MCP Toolkit tools on and off in Edit > Project Settings > AI > Unity MCP > Tools. Tools are organized into collapsible groups:

• MCP Toolkit — General tools (GetToolkitInfo, GameViewCapture, ForceDomainRefresh)
• MCP Toolkit - Project Settings — All project settings read/write tools
• MCP Toolkit - Build — Build configuration tools
• MCP Toolkit - Scene View — Scene View camera tools
• MCP Toolkit - Input System — Input Action tools
• MCP Toolkit - Recorder — Recorder configuration and recording tools

Write tools are disabled by default and must be explicitly enabled by the user.

Conditional Compilation

Some tools depend on optional Unity packages (Input System, ProBuilder, Timeline, NavMesh). The toolkit uses versionDefines in the assembly definition combined with #if preprocessor guards so these tools compile only when their package is installed. When the package is absent, Unity silently ignores the missing assembly reference and the guarded code is excluded from compilation. The tools are completely invisible — they don't appear in the MCP settings UI and the registry never sees them.

Package	Symbol	Min Version
com.unity.inputsystem	MCP_TOOLKIT_INPUT_SYSTEM	1.0.0
com.unity.recorder	MCP_TOOLKIT_RECORDER	5.0.0

Future optional subsystems (ProBuilder, Timeline, NavMesh) will follow the same pattern. See the Input System files under Editor/Tools/InputSystem/ for a working reference.

Contributing

This toolkit is meant to grow over time with tools the community finds useful. If you have an idea for a tool that would make your workflow better, chances are others would benefit from it too. Contributions are welcome and encouraged!

Please keep the following in mind:

• Follow the Unity convention for file structure. Tool logic goes in Editor/Tools/<Subsystem>/, parameter records are co-located with their tools. One file per tool, one file per params record.
• Optional package dependencies: If your tool depends on a package that might not be installed, wrap the entire .cs file in #if MCP_TOOLKIT_<PACKAGE> / #endif and add both a references entry and a versionDefines entry to McpToolkit.Editor.asmdef. See the Input System tools for the exact pattern.
• AI-assisted contributions are welcome, but a human must review the code and PR description before submitting. PRs that appear to be 100% vibe-coded without human review will be sent back.

License

This project is dedicated to the public domain under the CC0 1.0 Universal license. You can copy, modify, and distribute it without asking permission or giving credit.