Ue MCP

What ue-mcp MCP server does

The ue-mcp MCP server gives an AI assistant read and write access to an Unreal Engine project through categorized MCP tools. The documented surface includes 29 categories and more than 2,030 actions, covering level editing, Blueprint graphs, materials, asset import and management, animation, Niagara, landscape, foliage, PCG, audio, UI, gameplay systems, networking, Sequencer, project configuration, and build operations.

It can also inspect INI files, C++ headers, and asset listings directly from the filesystem when the editor is not running. For Unreal Engine 5.8 and later, the server can expose tools from Epic's native AI Toolset Registry as epic_* actions. A built-in demo can create and later clean up a 19-step procedural scene.

How it works

An AI client starts the TypeScript/Node.js MCP process over stdio. The process communicates over WebSocket with a C++ bridge plugin running inside the Unreal Editor, which uses Unreal's editor APIs. Direct filesystem access handles project information that does not require a live editor connection.

The ue-mcp MCP server also supports YAML flows stored in ue-mcp.yml beside the .uproject file. A flow combines tool actions into one callable sequence and can use step references, retries, rollback, shell steps, and custom JavaScript or TypeScript tasks. Configuration is hot-reloaded, so flow edits can be tested without restarting the server.

Setup and configuration

Run npx ue-mcp init from the project directory to begin interactive setup. The initializer locates a .uproject, lets you select tool categories, deploys the C++ bridge plugin, enables required Unreal plugins, and configures supported MCP clients. Restart the Unreal Editor once after initialization so the bridge loads.

For later updates, run npx ue-mcp update from the project directory. This updates the npm package, redeploys the bridge, and rebuilds it. If the connection fails, npx ue-mcp doctor checks common setup problems, including an unrestarted editor, a bridge compilation failure, or a mismatch between the configured and open projects.

Manual MCP configuration can launch npx with ue-mcp@latest and the path to a .uproject file. The package also supports npm-installed extension plugins, which can add actions to existing categories or provide new categories backed by C++ handlers.

Tools and capabilities

The documented categories support tasks such as:

• Creating, moving, deleting, and inspecting actors, lights, volumes, splines, and water bodies.
• Reading and editing Blueprint graphs, pins, properties, and compilation results.
• Creating materials and instances, editing expression graphs, and setting parameters.
• Importing and managing meshes, textures, animations, data tables, and other assets.
• Authoring Niagara, PCG, landscape, foliage, audio, UI, StateTree, GAS, navigation, and gameplay systems.
• Inspecting reflection data, gameplay tags, SaveGame data, logs, editor state, and build output.
• Running project builds, Python or console commands, PIE, Sequencer operations, and the built-in demo.

Limitations and notes

Write access changes the Unreal project, so the documentation describes configurable write guards that can block mutations or require confirmation. A source-control guard can also gate writes to checked-in assets based on source-control state.

The bridge plugin must compile and be loaded by the correct Unreal project. The editor must be running for editor API operations, while the documented filesystem reads can work with the editor closed. Native Epic Toolset Registry actions are identified for UE 5.8 and later. Agent skills ship with the package, but they load automatically only in clients that support skills.