Unity MCP Server — AI-Powered Unity Editor & Hub Control

The most comprehensive Model Context Protocol (MCP) server for Unity game development. Connect Claude, Cursor, Windsurf, or any MCP-compatible AI assistant to Unity Editor and Unity Hub with 281 tools across 30+ categories. Built and maintained by AnkleBreaker Studio.

AnkleBreaker Unity MCP turns your AI assistant into a full Unity co-pilot — create scenes, manipulate GameObjects, manage components, run builds, profile performance, edit Shader Graphs, control Amplify Shader Editor, sculpt terrain, bake NavMesh, manage animations, run multiplayer playmode scenarios, and much more — all without leaving your AI chat. Works with Claude Desktop, Claude Cowork, Cursor, Windsurf, and any tool that supports the Model Context Protocol.

Neon Brick Breaker — Built from scratch by AI in under 5 minutes

Claude creates the entire game: scene setup, neon materials with bloom post-processing, brick grid layout, game scripts, VFX, and UI — all through Unity MCP commands.

3D Medieval Village — AI-generated terrain, houses, and environment

From an empty scene to a fully decorated village: terrain sculpting, material creation, procedural house building via C# editor scripts, trees, fences, and pathways.

3D Castle — Complete level with FPS walkthrough

AI builds a multi-room castle with courtyard, throne room, armory, and guard room. Adjusts lighting, spawns the player, and runs an FPS walkthrough to verify the result.

How It Works — AI → MCP Server → Unity Plugin → Unity Editor

The Model Context Protocol connects your AI assistant to Unity through a lightweight bridge. Commands flow from your AI chat directly into the editor in real-time.

Features

281 tools covering the full Unity workflow:

Category	Tools
Unity Hub	List/install editors, manage modules, set install paths
Scenes	Open, save, create scenes, get full hierarchy tree with pagination
GameObjects	Create (primitives/empty), delete, duplicate, reparent, activate/deactivate, transform (world/local)
Components	Add, remove, get/set any serialized property, wire object references, batch wire
Assets	List, import, delete, search, create prefabs, create & assign materials
Scripts	Create, read, update C# scripts
Builds	Multi-platform builds (Windows, macOS, Linux, Android, iOS, WebGL)
Console & Compilation	Read/clear Unity console logs (errors, warnings, info); get C# compilation errors via CompilationPipeline (independent of console buffer)
Testing	Run EditMode/PlayMode tests, poll results, list available tests via Unity Test Runner API
Play Mode	Play, pause, stop
Editor	Execute menu items, run C# code, get editor state, undo/redo
Project	Project info, packages (list/add/remove/search), render pipeline, build settings
Animation	List clips & controllers, get parameters, play animations
Prefab	Open/close prefab mode, get overrides, apply/revert changes
Physics	Raycasts, sphere/box casts, overlap tests, physics settings
Lighting	Manage lights, environment, skybox, lightmap baking, reflection probes
Audio	AudioSources, AudioListeners, AudioMixers, play/stop, mixer params
Terrain	Create/modify terrains, paint heightmaps/textures, manage terrain layers, trees, details
Navigation	NavMesh baking, agents, obstacles, off-mesh links
Particles	Particle system creation, inspection, module editing
UI	Canvas, UI elements, layout groups, event system
Tags & Layers	List/add/remove tags, assign tags & layers
Selection	Get/set editor selection, find by name/tag/component/layer/tag
Graphics	Scene and game view capture (inline images for visual inspection)
Input Actions	Action maps, actions, bindings (Input System package)
Assembly Defs	List, inspect, create, update .asmdef files
ScriptableObjects	Create, inspect, modify ScriptableObject assets
Constraints	Position, rotation, scale, aim, parent constraints
LOD	LOD group management and configuration
Profiler	Start/stop profiling, stats, deep profiles, save profiler data
Frame Debugger	Enable/disable, draw call list & details, render targets
Memory Profiler	Memory breakdown, top consumers, snapshots (com.unity.memoryprofiler)
Shader Graph	List, inspect, create, open Shader Graphs & Sub Graphs; VFX Graphs
Amplify Shader Editor	Full graph manipulation — create, inspect, add/remove/connect/disconnect/duplicate nodes, set properties, templates, save/close (if installed)
MPPM Scenarios	List, activate, start, stop multiplayer playmode scenarios; get status & player info
Multi-Instance	Discover and switch between multiple running Unity Editor instances
Multi-Agent	List active agents, get agent action logs, queue monitoring
UMA (Unity Multipurpose Avatar)	Create slots, overlays, wardrobe recipes from FBX; equip/unequip items on DCA; browse/rebuild Global Library
Project Context	Auto-inject project-specific docs and guidelines for AI agents

Architecture

Claude / AI Assistant ←→ MCP Server (this repo) ←→ Unity Editor Plugin (HTTP bridge)
                                ↕
                          Unity Hub CLI

This server communicates with:

• Unity Hub via its CLI (supports both modern --headless and legacy -- --headless syntax)
• Unity Editor via the companion unity-mcp-plugin which runs an HTTP API inside the editor

268 Tools Across 30+ Categories

Scene management, GameObjects, components, physics, terrain, Shader Graph, Amplify Shader Editor, profiling, animation, NavMesh, builds, multiplayer, and more.

Two-Tier Tool System

To avoid overwhelming MCP clients with 281 tools, the server uses a two-tier architecture:

• Core tools (~70) are always exposed directly
• Advanced tools (~130+) are accessed via a single unity_advanced_tool proxy with lazy loading

This keeps the tool count manageable for clients like Claude Desktop and Cowork while still providing access to every Unity feature. Use unity_list_advanced_tools to discover all advanced tools by category.

Multi-Instance Support

The server automatically discovers all running Unity Editor instances on startup. If only one instance is found, it auto-connects. If multiple instances are running (e.g., main editor + ParrelSync clones), it prompts you to select which one to work with.

Port Resilience — The server includes a multi-layer protection system for reliable multi-project workflows:

• Port Identity Validation — When restoring a saved connection, the server verifies the instance identity (project name + path) matches the expected target. If Unity restarts and a different project grabs the port, the server detects this and re-discovers the correct instance.
• Compile-Time Resilience — During long Unity compiles (when the editor is unresponsive), the server checks the shared instance registry. If the registry entry is fresh (updated within the last 5 minutes via heartbeat), the connection is preserved instead of dropped.
• Crash Detection — The plugin sends a heartbeat every 30 seconds to the instance registry. If Unity crashes and the heartbeat stops, the server detects the stale registry entry (>5 minutes old) and clears it, allowing proper re-discovery.
• Port Affinity — The plugin remembers its last-used port via EditorPrefs and reclaims it on restart, minimizing port swaps across editor restarts.

Quick Start

1. Install the Unity Plugin

In Unity: Window > Package Manager > + > Add package from git URL:

https://github.com/AnkleBreaker-Studio/unity-mcp-plugin.git

2. Install this MCP Server

git clone https://github.com/AnkleBreaker-Studio/unity-mcp-server.git
cd unity-mcp-server
npm install

3. Add to Claude Desktop

Open Claude Desktop > Settings > Developer > Edit Config, and add:

{
  "mcpServers": {
    "unity": {
      "command": "node",
      "args": ["C:/path/to/unity-mcp-server/src/index.js"],
      "env": {
        "UNITY_HUB_PATH": "C:\\Program Files\\Unity Hub\\Unity Hub.exe",
        "UNITY_BRIDGE_PORT": "7890"
      }
    }
  }
}

Restart Claude Desktop. Done!

4. Try It

• "List my installed Unity editors"
• "Show me the scene hierarchy"
• "Create a red cube at position (0, 2, 0) and add a Rigidbody"
• "Profile my scene and show the top memory consumers"
• "List all Shader Graphs in my project"
• "Build my project for Windows"
• "List and start my MPPM multiplayer scenarios"
• "Capture a screenshot of my scene view"
• "Show me the active agent sessions"

Configuration

Environment Variable	Default	Description
UNITY_HUB_PATH	C:\Program Files\Unity Hub\Unity Hub.exe	Unity Hub executable path
UNITY_BRIDGE_HOST	127.0.0.1	Editor bridge host
UNITY_BRIDGE_PORT	7890	Editor bridge port (auto-discovered when using multi-instance)
UNITY_BRIDGE_TIMEOUT	30000	Request timeout in ms
UNITY_PORT_RANGE_START	7890	Start of port scan range for multi-instance discovery
UNITY_PORT_RANGE_END	7899	End of port scan range
UNITY_REGISTRY_STALENESS_TIMEOUT	300000	Registry entry staleness timeout in ms (crash detection)
UNITY_RESPONSE_SOFT_LIMIT	2097152	Response size soft limit in bytes (warning)
UNITY_RESPONSE_HARD_LIMIT	4194304	Response size hard limit in bytes (truncation)
UNITY_MCP_DEBUG	false	Enable debug logging for troubleshooting

The Unity plugin also has its own settings accessible via the Dashboard (Window > MCP Dashboard) for port, auto-start, and per-category feature toggles.

Optional Package Support

Some tools activate automatically when their packages are detected in the Unity project:

Package / Asset	Features Unlocked
com.unity.memoryprofiler	Memory snapshot capture via MemoryProfiler API
com.unity.shadergraph	Shader Graph creation, inspection, opening
com.unity.visualeffectgraph	VFX Graph listing and opening
com.unity.inputsystem	Input Action map and binding inspection
com.unity.multiplayer.playmode	MPPM scenario listing, activation, start/stop, player info
Amplify Shader Editor (Asset Store)	Amplify shader listing, inspection, opening
UMA 2 (Asset Store)	UMA SlotDataAsset/OverlayDataAsset creation, WardrobeRecipe pipeline, Global Library management, DCA wardrobe equip/unequip

Features for uninstalled packages return helpful messages explaining what to install.

Requirements

• Node.js 18+
• Unity Hub (for Hub tools)
• Unity Editor with unity-mcp-plugin installed (for Editor tools)

Troubleshooting

"Connection failed" errors — Make sure Unity Editor is open and the plugin is installed. Check the Unity Console for [MCP Bridge] Server started on port 7890.

"Unity Hub not found" — Update UNITY_HUB_PATH in your config to match your installation.

"Category disabled" errors — A feature category may be toggled off. Open Window > MCP Dashboard in Unity to check category settings.

Port conflicts — Change UNITY_BRIDGE_PORT in your Claude config and update the port in Unity's MCP Dashboard settings.

Why AnkleBreaker Unity MCP?

AnkleBreaker Unity MCP is the most comprehensive MCP integration for Unity, purpose-built to leverage the full power of Claude Cowork and other AI assistants. Here's how it compares to alternatives:

Feature Comparison

Feature	AnkleBreaker MCP	Bezi	Coplay MCP	Unity AI
Total Tools	281	~30	34	Limited (built-in)
Feature Categories	30+	~5	~5	N/A
Non-Blocking Editor	✅ Full background operation	❌ Freezes Unity during tasks	✅	✅
Open Source	✅ AnkleBreaker Open License	❌ Proprietary	✅ MIT License	❌ Proprietary
Claude Cowork Optimized	✅ Two-tier lazy loading	❌ Not MCP-based	⚠️ Basic	❌ Not MCP-based
Multi-Instance Support	✅ Auto-discovery	❌	❌	❌
Multi-Agent Support	✅ Session tracking + queuing	❌	❌	❌
Unity Hub Control	✅ Install editors & modules	❌	❌	❌
Scene Hierarchy	✅ Full tree + pagination	⚠️ Limited	⚠️ Basic	⚠️ Limited
Physics Tools	✅ Raycasts, overlap, settings	❌	❌	❌
Terrain Tools	✅ Full terrain pipeline	❌	❌	❌
Shader Graph	✅ Create, inspect, open	❌	❌	❌
Profiling & Debugging	✅ Profiler + Frame Debugger + Memory	❌	❌	⚠️ Basic
Animation System	✅ Controllers, clips, parameters	⚠️ Basic	⚠️ Basic	⚠️ Basic
NavMesh / Navigation	✅ Bake, agents, obstacles	❌	❌	❌
Particle Systems	✅ Full module editing	❌	❌	❌
MPPM Multiplayer	✅ Scenarios, start/stop	❌	❌	❌
Visual Inspection	✅ Scene + Game view capture	❌	⚠️ Limited	❌
Play Mode Resilient	✅ Survives domain reload	❌	❌	N/A
Port Resilience	✅ Identity validation + crash detection	❌	❌	N/A
Project Context	✅ Custom docs for AI agents	❌	❌	⚠️ Built-in only

Cost Comparison

AnkleBreaker Unity MCP is completely free and open source. The prices below reflect only the cost of the AI assistant (Claude) itself — the MCP plugin and server are $0.

Solution	Monthly Cost	What You Get
AnkleBreaker MCP (free) + Claude Pro	$20/mo	281 tools, full Unity control, open source — MCP is free, price is Claude only
AnkleBreaker MCP (free) + Claude Max 5x	$100/mo	Same + 5x usage for heavy workflows — MCP is free, price is Claude only
AnkleBreaker MCP (free) + Claude Max 20x	$200/mo	Same + 20x usage for teams/studios — MCP is free, price is Claude only
Bezi Pro	$20/mo	~30 tools, 800 credits/mo, freezes Unity
Bezi Advanced	$60/mo	~30 tools, 2400 credits/mo, freezes Unity
Bezi Team	$200/mo	3 seats, 8000 credits, still freezes Unity
Unity AI	Included with Unity Pro/Enterprise	Limited AI tools, Unity Points system, no MCP
Coplay MCP	Free (beta)	34 tools, basic categories

Key Advantages

vs. Bezi: Bezi runs as a proprietary Unity plugin with its own credit-based billing — $20–$200/mo on top of your AI subscription. It has historically suffered from freezing the Unity Editor during AI tasks, blocking your workflow. AnkleBreaker MCP is completely free and open source, runs entirely in the background with zero editor impact, and offers 8x more tools — the only cost is your existing Claude subscription.

vs. Coplay MCP: Coplay MCP provides 34 tools across ~5 categories. AnkleBreaker MCP delivers 281 tools across 30+ categories including advanced features like physics raycasts, terrain editing, shader graph management, profiling, NavMesh, particle systems, and MPPM multiplayer — none of which exist in Coplay. Our two-tier lazy loading system is specifically optimized for Claude Cowork's tool limits.

vs. Unity AI: Unity AI (successor to Muse) is built into Unity 6.2+ but limited to Unity's own AI models and a credit-based "Unity Points" system. It cannot be used with Claude or any external AI assistant, has no MCP support, and offers a fraction of the automation capabilities. AnkleBreaker MCP works with any MCP-compatible AI while giving you full control over which AI models you use.

Support the Project

If Unity MCP helps your workflow, consider supporting its development! Your support helps fund new features, bug fixes, documentation, and more open-source game dev tools.

Sponsor tiers include priority feature requests — your ideas get bumped up the roadmap! Check out the tiers on GitHub Sponsors or Patreon.

What's New in v2.27.0

• UMA (Unity Multipurpose Avatar) integration — 13 new tools for the complete UMA asset pipeline. Create SlotDataAssets, OverlayDataAssets, and WardrobeRecipes directly from FBX files, equip/unequip wardrobe items on DynamicCharacterAvatar, browse and manage the UMA Global Library, verify recipes for missing references, and more. Requires UMA 2 (available on the Asset Store). Registered as advanced tools accessible via unity_advanced_tool.

What's New in v2.26.0

• Compilation error detection — New unity_get_compilation_errors tool retrieves C# compilation errors and warnings directly from Unity's CompilationPipeline API. Unlike unity_console_log, this is independent of the console log buffer — not affected by console clear, Play Mode log flooding, or buffer overflow. Supports filtering by severity (error, warning, all) and count limit. Registered as a core tool (always directly accessible, not behind unity_advanced_tool).

What's New in v2.25.0

• Parallel-safe instance routing — When multiple AI agents (e.g. Claude Cowork tasks) share the same MCP process, each agent can now include a port parameter in every unity_* tool call to guarantee routing to the correct Unity Editor instance. This prevents cross-agent contamination where one task's unity_select_instance could redirect another task's commands to the wrong project.
• Per-request port override — A new stateless routing mechanism bypasses the shared per-agent state entirely. The port parameter is extracted by middleware before the tool handler runs, used for routing, then stripped from the args. This is safe because MCP stdio transport processes requests sequentially.
• Schema injection — The optional port parameter is automatically injected into every unity_* tool schema (except unity_list_instances, unity_select_instance, and unity_hub_*), so AI assistants see it as a legitimate parameter and pass it consistently.
• Enhanced select_instance response — unity_select_instance now returns explicit routing instructions telling the AI to include port in all subsequent calls.

Frequently Asked Questions

What is Unity MCP? Unity MCP (Model Context Protocol) is an open-source integration that connects AI assistants like Claude, Cursor, and Windsurf to the Unity Editor and Unity Hub. It allows AI to directly control Unity — creating scenes, placing objects, writing scripts, running builds, profiling, and more — through a standardized protocol.

How does AnkleBreaker Unity MCP compare to other Unity AI tools? AnkleBreaker Unity MCP offers 281 tools across 30+ categories, making it the most comprehensive Unity MCP integration available. Competitors like Bezi (~30 tools) and Coplay MCP (34 tools) cover a fraction of Unity's features. Unlike Bezi, AnkleBreaker MCP is free, open source, and doesn't freeze the Unity Editor during AI operations.

Does it work with Claude Desktop / Claude Cowork? Yes. AnkleBreaker Unity MCP is purpose-built for Claude Desktop and Claude Cowork. It uses a two-tier lazy loading system to stay within MCP client tool limits while exposing all 281 tools on demand.

Does it work with Cursor, Windsurf, or other MCP clients? Yes. Any AI tool that supports the Model Context Protocol can connect to this server. This includes Cursor, Windsurf, Claude Desktop, Claude Cowork, and any other MCP-compatible client.

What Unity versions are supported? Unity 2021.3 LTS and newer, including Unity 2022.3 LTS and Unity 6. The plugin is installed via Unity Package Manager (UPM).

Is it free? Yes. Both the MCP server and the Unity plugin are completely free and open source under the AnkleBreaker Open License. The only cost is your AI assistant subscription (e.g., Claude Pro at $20/month).

Can multiple AI agents use it simultaneously? Yes. The server supports multi-agent operation with session tracking, action logging, and queued execution to prevent conflicts. It also supports multiple Unity Editor instances running side-by-side.

Does it support Amplify Shader Editor? Yes. If Amplify Shader Editor is installed in your project, 23 additional tools are unlocked for full shader graph manipulation — creating nodes, connecting them, setting properties, using templates, and more. Projects without Amplify work perfectly; the tools gracefully report that ASE is not installed.

Related Projects

• unity-mcp-plugin — The companion Unity Editor plugin (UPM package) that this server connects to
• Model Context Protocol — The open standard that powers this integration
• Claude Desktop — Anthropic's AI assistant with built-in MCP support
• AnkleBreaker Studio — The game studio behind this project

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Keywords (for search engines)

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License

AnkleBreaker Open License v1.0 — see LICENSE

This license requires: (1) including the copyright notice, (2) displaying "Made with AnkleBreaker MCP" (or "Powered by AnkleBreaker MCP") attribution in any product built with it (personal/educational use is exempt), and (3) reselling the tool is forbidden — you may not sell, sublicense, or commercially distribute this software or derivatives of it. See the full LICENSE for details.