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Unity-MCP by IvanMurzak, a community Unity MCP server

CommunityRemoteLocal

Lets Claude, Cursor and other AI assistants build scenes, edit assets and write C# scripts inside the Unity Editor.

Unity-MCP lets Claude, Cursor and other AI assistants work inside the Unity Editor. They can build scenes, change objects and assets, write C# scripts and run tests. It can also run any C# code and delete assets and scripts, and the local server asks for no sign-in. Keep your project in version control before you let an agent loose on it.

Good for

  • Unity developers who want an assistant to edit scenes, materials and scripts for them
  • Solo and indie game makers prototyping layouts and objects fast
  • Teams that want to expose their own game tools to an AI agent
  • Developers who want an AI to play or test a built game through custom runtime tools

Works in

6 supported · 5 with issues · 3 should work

Tap an app to see how to set it up and any known problems.

Install Unity-MCP (AI Game Developer)

Claude Code

  1. 1

    Install the plugin in your Unity project: import the AI-Game-Dev-Installer.unitypackage or run `openupm add com.ivanmurzak.unity.mcp`.

  2. 2

    Open the project in Unity, then open Window > AI Game Developer.

  3. 3

    In the window, click Configure MCP (or Auto-generate skills, which the project recommends) and pick Claude Code. If your client is not listed, copy the raw JSON the window shows into its MCP config.

  4. 4

    Restart Claude Code so it picks up the new server.

Requires Unity project (path without spaces), ai-game.dev account.

This is not a standalone server: a Unity plugin runs inside your project and talks to the AI client. The project path cannot contain spaces. Sign-in is an OAuth browser flow with ai-game.dev (unity-mcp-cli login for the CLI route), and the config written for your client points at a per-project address on ai-game.dev. Your AI client has to support Skills or dynamic MCP tool updates. A self-hosted server (Docker image aigamedeveloper/mcp-server, or stdio) is also supported; see the README's Unity MCP Server setup.

From the project README. Source.

Tools

  • Searches your project's assets

    Searches your project's assets.

    Try: “Find all materials in my project”

    Read · assets-find

  • Reads the data of an asset file

    Reads the data of an asset file.

    Try: “Show the settings of this material”

    Read · assets-get-data

  • Finds a GameObject in the scene

    Finds a GameObject in the scene.

    Try: “Find the Player object”

    Read · gameobject-find

  • Lists the top-level objects in a scene

    Lists the top-level objects in a scene.

    Try: “What is in my main scene?”

    Read · scene-get-data

  • Lists the scenes open in the editor

    Lists the scenes open in the editor.

    Try: “Which scenes are open?”

    Read · scene-list-opened

  • Reads the Unity console logs

    Reads the Unity console logs.

    Try: “Show me the latest errors in the console”

    Read · console-get-logs

  • Takes a screenshot of the Game view

    Takes a screenshot of the Game view.

    Try: “Take a screenshot of the Game view”

    Read · screenshot-game-view

  • Takes a screenshot of the Scene view

    Takes a screenshot of the Scene view.

    Try: “Take a screenshot of the Scene view”

    Read · screenshot-scene-view

  • Takes a screenshot from a camera

    Takes a screenshot from a camera.

    Try: “Capture what the main camera sees”

    Read · screenshot-camera

  • Renders one object on its own from a chosen angle

    Renders one object on its own from a chosen angle.

    Try: “Show the Player model from the front”

    Read · screenshot-isolated

  • Reads a script file

    Reads a script file.

    Try: “Show me PlayerController.cs”

    Files · script-read

  • Reads the data of a Unity object

    Reads the data of a Unity object.

    Try: “Show the data of the selected object”

    Read · object-get-data

Read from the source code

Pros and cons

Good

  • Free and open source under Apache-2.0, with no account needed for local use.
  • Works inside the Unity Editor and, with your own tools, inside a built game.
  • Any C# method in your project can become a custom tool for the agent.
  • Setup is documented for Claude Code, Claude Desktop, Cursor, VS Code, Codex, Gemini CLI and more.
  • Ships its own server program, so no Python is needed.
  • Active maintainer with frequent releases.

Watch out

  • The default tool set costs about 36k tokens of context.
  • Runs any C# code and deletes assets by default, with no read-only mode.
  • The local server needs no sign-in unless you turn it on.
  • HTTP connections drop after idle time in Cursor and VS Code.
  • Needs Unity 2022.3 or newer, and the project path cannot contain spaces.
  • Unity's own free CLI is the first-party option on Unity 6.0 LTS and newer.

Permissions

high risk · 6 things to watch

High risk

An AI agent can run any C# code and delete assets and scripts in your project, and the local server asks for no sign-in by default. Keep the project in version control, switch off tools you do not need, and remember that hiding a tool does not stop a call by name.

What it can do

  • Read your data
  • Create and change things
  • Delete things
  • Read-only mode

Watch out for

  • It can run any C# code in the Editor

    One default tool compiles and runs a C# snippet, and another can call any method it finds. Review what the agent plans to run, and work in a project under version control. github.com

  • It can delete assets and scripts and add packages

    These tools change the project directly. Commit before long agent sessions so you can roll back. github.com

  • The local server has no sign-in by default

    Any client that reaches the port can use it. Turn on token mode before you expose the port, for example when running the Docker image. github.com

  • Hiding a tool does not block it

    The tool filter only removes tools from the list the client sees. A hidden tool still runs if a client calls it by name. github.com

  • Cloud mode signs you in to ai-game.dev

    The credential is stored on your machine. Custom mode keeps everything local and needs no account. github.com

  • The server program downloads on first load

    The plugin fetches the server into your project's Library folder the first time it loads, so the first start needs internet access. github.com

Security advisories

No published security advisories as of Nov 1, 2026.

Technical details
Turning on read-onlyNo read-only mode. You can switch off individual tools in the AI Game Developer window, or list allowed tools in UNITY_MCP_TOOLS, but the README says a hidden tool still runs if a client calls it by name.
Talks toai-game.dev (Cloud mode only). Download of the server program on first load
Sign-in and keysCloud mode stores your ai-game.dev credential in ~/.ai-game-dev/credentials.json.

Alternatives

On Unity 6.0 LTS or newer, start with Unity CLI, which is free and made by Unity. Pick CoplayDev's MCP for Unity if you run Unity 2021.3, and Unity-MCP when you want no Python or tools inside a built game.

ServerOfficialRunsCan change thingsGitHub stars
For Unity
Unity-MCPThis pageCommunityHostedLocalYes4.6K
mcp-unityCommunityLocalYes2K
Other tools for the same job
Unity CLIOfficialLocalYes–
MCP for UnityCommunityLocalYes–

What people say

People like how well it writes Unity code and how fast the maintainer responds, and dislike its heavy context cost and dropped connections.

What people like

  • Writes Unity C# code well, even when broader agent tasks get confused.
  • A studio user says it has become part of their daily workflow.
  • The maintainer answers reports fast and ships fixes, such as the tool-disable window added after a token complaint.
  • Users find the Skills plus CLI route more stable than a long-lived MCP connection.

Common complaints

  • The default tool set is heavy, about 36k tokens of tool definitions in one Claude Code session.
  • HTTP connections drop after idle time in Cursor, VS Code and Kilo Code and need a manual restart.
  • The connection can get stuck on Connecting after the cloud server goes offline briefly.
  • The test-running tool has hung or deadlocked the Editor in some versions.

In their words

2 more quotes

Questions

Is Unity-MCP free?

Yes. The plugin and the MCP server are free and open source under Apache-2.0, and you bring your own AI assistant. Paid ai-game.dev plans from $25 a month only add hosted AI models and asset generation.

Do I need an ai-game.dev account?

Not for local use. Custom mode runs the server on your machine with no account. Cloud mode, which the command-line setup uses by default, signs you in through your browser.

Is it safe to let an agent use it?

It can run any C# code and delete assets and scripts, and the local server has no sign-in by default. Keep the project in version control and switch off tools you do not need.

Why does it use so much of my context window?

The full default tool set is large, and one user measured about 36k tokens in Claude Code. Turn off unused tools in the AI Game Developer window, or use the Skills route, which the maintainer says is cheaper.

If I hide a tool, can the AI still use it?

Yes, if the client calls it by name. The filter only removes tools from the list the client sees, so it does not work as a safety lock.

Does Unity have its own official MCP server?

Yes. Unity replaced the MCP server in its AI Assistant package with the free Unity CLI, and its MCP mode needs Unity 6.0 LTS or newer. Unity says third-party packages like this one are unaffected.

Unity-MCP vs CoplayDev's MCP for Unity?

Unity-MCP ships its own server program, so no Python is needed, and it can run tools inside a built game. CoplayDev's server needs Python 3.10 or newer through uv and supports Unity back to 2021.3.

Which Unity versions does it support?

Unity 2022.3 or newer, per the project wiki. The project path must not contain spaces.

Can the AI control my game while it is running?

Yes, but only through tools you write. A built game can connect to the server, and it exposes no tools by default. The README's chess bot sample shows how.

What is the Unity-MCP server URL?

Cloud mode uses https://ai-game.dev/mcp. Local mode runs on your own machine, so use the details the AI Game Developer window shows for your project.

Examples

  • Build a quick test layout in the open scene

    Create 3 cubes in a circle with radius 2

    Source
  • Understand an unfamiliar scene before editing it

    Explain my scene hierarchy

    Source
  • Create a material and apply it to a new object

    Create metallic golden material and attach it to a new sphere gameObject

    Source
  • Stack objects to test physics or layout

    Create 3 spheres on top of each other

    Source
  • Let an LLM play a chess bot's turns inside a built game through custom runtime tools

    Source

Information

updated Nov 2, 2026

Publisher
Community
Package
aigamedeveloper/mcp-server
Registry
Docker
Endpoint
https://ai-game.dev/mcp
Transport
stdio, Streamable HTTP
Version
0.17.1
License
Apache-2.0
Last commit
Oct 31, 2026
Open issues
45
Listed in
Official MCP registry

WebsiteUnity tools docsGitHubDockerOfficial MCP RegistryConnect any clientChangelogPricingIssues

Other Unity MCP servers

Sources

Docs, issue trackers and discussions this page is built from. Issues, quotes and findings above link to their own source.

Show all 17
  1. Unity-MCP README · github.com
  2. unity-mcp-cli README · github.com
  3. Unity-MCP README: Variables · github.com
  4. Unity-MCP Wiki: FAQ · github.com
  5. Unity CLI as the replacement for the in-Editor MCP server · docs.unity.com
  6. CoplayDev/unity-mcp · github.com
  7. Default MCP tools · github.com
  8. Installation Guide · github.com
  9. AI Game Developer pricing · ai-game.dev
  10. 36K tokens consumed by context window always!!! · github.com
  11. Error reading from async stream, we will reconnect · github.com
  12. MCP endpoint info · ai-game.dev
  13. Thank you for your plugin · github.com
  14. streamableHttp: 202 response never completes · github.com
  15. Stuck connection status. · github.com
  16. Test runner hangs the Editor · github.com
  17. CoderGamester/mcp-unity · github.com

Facts from the official MCP registry, GitHub, npm, PyPI and the Docker catalog. Updated Nov 2, 2026.