* Fix Git URL in README for package installation Updated the Git URL for adding the package to include the branch name. * fix: Clean up Claude Code config from all scopes to prevent stale config conflicts (#664) - Add RemoveFromAllScopes helper to remove from local/user/project scopes - Use explicit --scope local when registering - Update manual snippets to show multi-scope cleanup - Handle legacy 'unityMCP' naming in all scopes Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com> * fix: Make Claude Code status check thread-safe (#664) The background thread status check was accessing main-thread-only Unity APIs (Application.platform, EditorPrefs via HttpEndpointUtility and AssetPathUtility), causing "GetString can only be called from main thread" errors. Now all main-thread-only values are captured before Task.Run() and passed as parameters to CheckStatusWithProjectDir(). Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com> * fix: Persist client dropdown selection and remove dead IO code - Remember last selected client in EditorPrefs so it restores on window reopen (prevents hiding config issues by defaulting to first client) - Remove dead Outbound class, _outbox BlockingCollection, and writer thread that was never used (nothing ever enqueued to outbox) - Keep only failure IO logs, remove verbose success logging Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com> * feat: Auto-detect beta package to enable UseBetaServer + workflow updates - Add IsPreReleaseVersion() helper to detect beta/alpha/rc package versions - UseBetaServer now defaults to true only for prerelease package versions - Main branch users get false default, beta branch users get true default - Update beta-release.yml to set Unity package version with -beta.1 suffix - Update release.yml to merge beta → main and strip beta suffix - Fix CodexConfigHelperTests to explicitly set UseBetaServer for determinism - Use EditorConfigurationCache consistently for UseBetaServer access Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com> * fix: Address code review feedback for thread-safety and validation - Add thread-safe overloads for GetBetaServerFromArgs/List that accept pre-captured useBetaServer and gitUrlOverride parameters - Use EditorConfigurationCache.SetUseBetaServer() in McpAdvancedSection for atomic cache + EditorPrefs update - Add semver validation guard in beta-release.yml before version arithmetic - Add semver validation guard in release.yml after stripping prerelease suffix Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com> * fix: Complete thread-safety for GetBetaServerFromArgs overloads - Add packageSource parameter to thread-safe overloads to avoid calling GetMcpServerPackageSource() (which uses EditorPrefs) from background threads - Apply quoteFromPath logic to gitUrlOverride and packageSource paths to handle local paths with spaces correctly Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com> * fix: Patch legacy connection pool in transport tests to prevent real Unity discovery The auto-select tests were failing because they only patched PluginHub but not the fallback legacy connection pool discovery. When PluginHub returns no results, the middleware falls back to discovering instances via get_unity_connection_pool(), which found the real running Unity. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com> |
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| .claude | ||
| .github | ||
| CustomTools/RoslynRuntimeCompilation | ||
| MCPForUnity | ||
| Server | ||
| TestProjects | ||
| docs | ||
| scripts | ||
| tools | ||
| .dockerignore | ||
| .gitignore | ||
| .mcpbignore | ||
| CLAUDE.md | ||
| LICENSE | ||
| README.md | ||
| docker-compose.yml | ||
| manifest.json | ||
| mcp_source.py | ||
README.md
| English | 简体中文 |
|---|
Proudly sponsored and maintained by Coplay -- the best AI assistant for Unity.
Create your Unity apps with LLMs! MCP for Unity bridges AI assistants (Claude, Cursor, VS Code, etc.) with your Unity Editor via the Model Context Protocol. Give your LLM the tools to manage assets, control scenes, edit scripts, and automate tasks.
Quick Start
Prerequisites
- Unity 2021.3 LTS+ — Download Unity
- Python 3.10+ and uv — Install uv
- An MCP Client — Claude Desktop | Cursor | VS Code Copilot | GitHub Copilot CLI | Windsurf
1. Install the Unity Package
In Unity: Window > Package Manager > + > Add package from git URL...
[!TIP]
https://github.com/CoplayDev/unity-mcp.git?path=/MCPForUnity#main
Want the latest beta? Use the beta branch:
https://github.com/CoplayDev/unity-mcp.git?path=/MCPForUnity#beta
Other install options (Asset Store, OpenUPM)
Unity Asset Store:
- Visit MCP for Unity on the Asset Store
- Click
Add to My Assets, then import viaWindow > Package Manager
OpenUPM:
openupm add com.coplaydev.unity-mcp
2. Start the Server & Connect
- In Unity:
Window > MCP for Unity - Click Start Server (launches HTTP server on
localhost:8080) - Select your MCP Client from the dropdown and click Configure
- Look for 🟢 "Connected ✓"
- Connect your client: Some clients (Cursor, Windsurf, Antigravity) require enabling an MCP toggle in settings, while others (Claude Desktop, Claude Code) auto-connect after configuration.
That's it! Try a prompt like: "Create a red, blue and yellow cube" or "Build a simple player controller"
Features & Tools
Key Features
- Natural Language Control — Instruct your LLM to perform Unity tasks
- Powerful Tools — Manage assets, scenes, materials, scripts, and editor functions
- Automation — Automate repetitive Unity workflows
- Extensible — Works with various MCP Clients
Available Tools
manage_asset • manage_editor • manage_gameobject • manage_components • manage_material • manage_prefabs • manage_scene • manage_script • manage_scriptable_object • manage_shader • manage_vfx • manage_texture • batch_execute • find_gameobjects • find_in_file • read_console • refresh_unity • run_tests • get_test_job • execute_menu_item • apply_text_edits • script_apply_edits • validate_script • create_script • delete_script • get_sha
Available Resources
custom_tools • unity_instances • menu_items • get_tests • gameobject • gameobject_components • prefab_api • prefab_info • prefab_hierarchy • editor_state • editor_selection • editor_prefab_stage • project_info • project_tags • project_layers
Performance Tip: Use batch_execute for multiple operations — it's 10-100x faster than individual calls!
Manual Configuration
If auto-setup doesn't work, add this to your MCP client's config file:
HTTP (default — works with Claude Desktop, Cursor, Windsurf):
{
"mcpServers": {
"unityMCP": {
"url": "http://localhost:8080/mcp"
}
}
}
VS Code:
{
"servers": {
"unityMCP": {
"type": "http",
"url": "http://localhost:8080/mcp"
}
}
}
Stdio configuration (uvx)
macOS/Linux:
{
"mcpServers": {
"unityMCP": {
"command": "uvx",
"args": ["--from", "mcpforunityserver", "mcp-for-unity", "--transport", "stdio"]
}
}
}
Windows:
{
"mcpServers": {
"unityMCP": {
"command": "C:/Users/YOUR_USERNAME/AppData/Local/Microsoft/WinGet/Links/uvx.exe",
"args": ["--from", "mcpforunityserver", "mcp-for-unity", "--transport", "stdio"]
}
}
}
Multiple Unity Instances
MCP for Unity supports multiple Unity Editor instances. To target a specific one:
- Ask your LLM to check the
unity_instancesresource - Use
set_active_instancewith theName@hash(e.g.,MyProject@abc123) - All subsequent tools route to that instance
Roslyn Script Validation (Advanced)
For Strict validation that catches undefined namespaces, types, and methods:
- Install NuGetForUnity
Window > NuGet Package Manager→ InstallMicrosoft.CodeAnalysisv5.0- Also install
SQLitePCLRaw.coreandSQLitePCLRaw.bundle_e_sqlite3v3.0.2 - Add
USE_ROSLYNtoPlayer Settings > Scripting Define Symbols - Restart Unity
Manual DLL installation (if NuGetForUnity isn't available)
- Download
Microsoft.CodeAnalysis.CSharp.dlland dependencies from NuGet - Place DLLs in
Assets/Plugins/folder - Ensure .NET compatibility settings are correct
- Add
USE_ROSLYNto Scripting Define Symbols - Restart Unity
Troubleshooting
- Unity Bridge Not Connecting: Check
Window > MCP for Unitystatus, restart Unity - Server Not Starting: Verify
uv --versionworks, check the terminal for errors - Client Not Connecting: Ensure the HTTP server is running and the URL matches your config
Detailed setup guides:
- Fix Unity MCP and Cursor, VSCode & Windsurf — uv/Python installation, PATH issues
- Fix Unity MCP and Claude Code — Claude CLI installation
- Common Setup Problems — macOS dyld errors, FAQ
Still stuck? Open an Issue or Join Discord
Contributing
See README-DEV.md for development setup. For custom tools, see CUSTOM_TOOLS.md.
- Fork → Create issue → Branch (
feature/your-idea) → Make changes → PR
Telemetry & Privacy
Anonymous, privacy-focused telemetry (no code, no project names, no personal data). Opt out with DISABLE_TELEMETRY=true. See TELEMETRY.md.
License: MIT — See LICENSE | Need help? Discord | Issues
Star History
Citation for Research
If you are working on research that is related to Unity-MCP, please cite us!@inproceedings{10.1145/3757376.3771417,
author = {Wu, Shutong and Barnett, Justin P.},
title = {MCP-Unity: Protocol-Driven Framework for Interactive 3D Authoring},
year = {2025},
isbn = {9798400721366},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
url = {https://doi.org/10.1145/3757376.3771417},
doi = {10.1145/3757376.3771417},
series = {SA Technical Communications '25}
}
Unity AI Tools by Coplay
Coplay offers 3 AI tools for Unity:
- MCP for Unity is available freely under the MIT license.
- Coplay is a premium Unity AI assistant that sits within Unity and is more than the MCP for Unity.
- Coplay MCP a free-for-now MCP for Coplay tools.
(These tools have different tech stacks. See this blog post comparing Coplay to MCP for Unity.)
Disclaimer
This project is a free and open-source tool for the Unity Editor, and is not affiliated with Unity Technologies.