FAQ

Short answers to the questions people ask most about Unreal MCP, the AI Game Developer plugin for Unreal Engine. For setup steps see Installation and Getting started.

General#

What is Unreal MCP?#

A C++ plugin for the Unreal Editor that exposes editor operations as MCP tools, so AI agents such as Claude Code, Cursor, Copilot, Codex or Gemini can inspect and change your project. It is part of AI Game Developer, alongside the Unity and Godot plugins.

Is it stable?#

It is in beta. The plugin, its bridge, unreal-mcp-cli and the editor window are released and tested in CI, and the current release is 0.26.2.

Which AI clients work?#

Any MCP client. unreal-mcp-cli setup-mcp and the editor's AI agent section write configs for Claude Code, Claude Desktop, Cursor, VS Code and Visual Studio Copilot, Rider (Junie), GitHub Copilot CLI, Gemini, Antigravity, Cline, Open Code, Codex and Kilo Code, plus a generic custom config. See Connecting AI clients.

Does it work with Claude Code?#

Yes. Run unreal-mcp-cli setup-mcp claude-code --path ./YourProject, start Claude Code in the project folder, and ask it about your level. Details are on Connecting AI clients.

Requirements#

Which Unreal Engine versions are supported?#

Unreal Engine 5.5 and newer. Releases are validated on 5.5, 5.6, 5.7 and 5.8. The optional extensions need 5.7 or newer.

Which operating systems?#

Windows (x64), macOS (Apple silicon and Intel) and Linux (x64).

Can I use it in a Blueprint-only project?#

The plugin is compiled for your project, so the project needs C++ support. Add any C++ class to the project once (this turns it into a C++ project), then install the plugin. You can keep building your game in Blueprints, and the agent can author Blueprints for you.

Do I need Node.js or .NET?#

Not with the AI Game Dev app. unreal-mcp-cli needs Node.js. You need the .NET 9 SDK only to build the bridge from source; packaged installs bundle it.

Installing#

Is it on Fab or the Epic Marketplace?#

Not yet. A Fab listing is planned. Today, install with the AI Game Dev app or unreal-mcp-cli.

How do I update?#

In the app, click Update Package when it appears; or run unreal-mcp-cli update ./YourProject, which also cleans the old build cache. See Installation.

Does the plugin end up in my shipped game?#

The editor tools never do: they are editor-only. To keep the whole plugin, including its bridge, out of packaged builds, add a TargetDenyList to the plugin entry in your .uproject, as shown on Installation.

Using it#

What can the AI actually do in the Unreal Editor?#

Query and change actors, components, assets, levels, DataTables, gameplay tags, Project Settings, Blueprint graphs, widgets and Level Sequences with RQL; author and compile Blueprints; read, write and compile C++; run editor Python; run console commands; and capture screenshots. See Tools.

Can I undo what the agent did?#

Changes made through rql-mutate are one undo step each, so Ctrl+Z in the editor reverts them. Project Settings writes, gameplay-tag edits and file changes (C++ source, saved assets) are not part of the undo history. Use version control for those.

Is there a Python escape hatch?#

Yes. python-execute runs Python with the full unreal API, and unreal-mcp-cli exec runs Python from a terminal.

Can I add my own tools?#

Yes, from any C++ plugin, without forking Unreal MCP. See Custom tools.

Can the AI control my running game?#

Yes, if you opt in. A runtime connection works in Play In Editor, Standalone and packaged Development builds, is off by default, refuses Shipping builds unless you compile that in, and exposes only tools your game registers. See in-game tools.

Accounts, privacy and cost#

Do I need an ai-game.dev account?#

For Cloud mode, yes: you sign in once per machine with the device-code flow. In Custom mode you can run everything against a local gamedev-mcp-server. See authentication.

Can I work fully offline or locally?#

Use Custom mode with a local server. Note that your AI client itself may still need its own internet connection to reach its model provider.

Where are my tokens stored?#

The machine sign-in is in ~/.ai-game-dev/credentials.json; per-project settings are in Saved/Config/UnrealMcp/, which version control ignores by default. Never commit a project .env file. See Configuration.

Does the plugin cost anything?#

The plugin and unreal-mcp-cli are open source under the Apache-2.0 license. Your AI client's own subscription is separate from AI Game Developer.

More help#

• Troubleshooting for specific errors.
• The general FAQ and quickstart.
• The Unreal Engine page for a one-page overview.