unreal-mcp

The most comprehensive MCP server for Unreal Engine — 127 tools across 16 subsystems, with 4 transport layers and no mandatory C++ plugin.

Beta — This project is under active development and testing. Tools are being validated against UE 5.6. Some tools may not work as expected. Bug reports and contributions are welcome.

Why This One?

	unreal-mcp	flopperam	chongdashu	kvick-games	ChiR24
Tools	127	~30	~20	~5	36
Transports	4	1	1	1	1
Requires C++ plugin	No	Yes	Yes	Yes	Yes
Build/package tools	Yes	No	No	No	Partial

Most Unreal MCP projects require compiling and installing a custom C++ plugin into your UE project. This one works out of the box by using Unreal's built-in Python and Remote Control plugins — zero-install beyond enabling what already ships with UE.

Quick Start

Prerequisites

• Node.js >= 18
• Unreal Engine 5.x with editor open
• Python Editor Script Plugin enabled (built-in) with Enable Remote Execution checked in its settings

Install

git clone https://github.com/YOUR_USERNAME/unreal-mcp.git
cd unreal-mcp
npm install
npm run build

Add to Claude Code

Per-project (from your UE project directory):

claude mcp add --transport stdio unreal-mcp -- node /path/to/unreal-mcp/dist/bin.js

Global (available in all projects):

claude mcp add --scope user --transport stdio unreal-mcp -- node /path/to/unreal-mcp/dist/bin.js

Then drop a .unrealmcp.json in each UE project:

{
  "projectPath": "."
}

Add to Claude Desktop

Add to %APPDATA%\Claude\claude_desktop_config.json (Windows) or ~/Library/Application Support/Claude/claude_desktop_config.json (macOS):

{
  "mcpServers": {
    "unreal": {
      "command": "node",
      "args": ["/path/to/unreal-mcp/dist/bin.js"],
      "env": {
        "UNREAL_MCP_PROJECT_PATH": "/path/to/YourProject.uproject"
      }
    }
  }
}

Tool Modules

Module	Tools	Description
actor	10	Spawn, delete, transform, select, duplicate, tag actors
asset	16	List, search, import, export, rename, delete, validate assets
blueprint	12	Create blueprints, add components/variables/functions, graph nodes
build	9	Build targets, cook content, package, generate project files
material	13	Create materials/instances, add expressions, wire graphs
console	6	Execute Python, console commands, screenshots, viewport camera
sequencer	8	Create sequences, add tracks/bindings, set playback range
animation	6	Animation blueprints, montages, modifiers, skeletal mesh
niagara	8	Spawn particle systems, set parameters (float/vector/color/bool)
editor-utils	8	Undo/redo, LOD generation, collision, lightmap UVs, utility widgets
testing	8	Automation tests, map check, data validation, Gauntlet
profiling	5	CSV profiling, Unreal Insights traces, stat commands
source-control	6	Status, checkout, checkin, revert, mark for add, diff
world-partition	4	Data layers, streaming sources, loaded cells
remote-control-presets	5	List/get/set preset properties, call preset functions
plugin	3	List, enable, disable plugins in .uproject

Architecture

MCP Client (Claude Code, Claude Desktop, etc.)
  ↕ stdio (MCP protocol)
unreal-mcp server
  ↕ 4 transport layers
Unreal Engine

Transport Layers

Transport	Protocol	Port	What It Needs
Python Remote Execution	UDP multicast + inverted TCP	6776	Python Editor Script Plugin (built-in)
Remote Control API	HTTP REST	30010	Remote Control API plugin (built-in)
Plugin Bridge	TCP, length-prefixed JSON	55557	Optional C++ plugin
Subprocess Runner	Spawns UAT/UBT processes	N/A	Engine path only

The server probes all transports on startup and tools gracefully degrade. Most tools use Python Remote Execution. Build tools use subprocess. The optional C++ plugin adds deep Blueprint graph manipulation.

Two Paths

• Core path (no plugin): Python + Remote Control covers ~95% of tools. Just enable the built-in UE plugins.
• Plugin path (optional): C++ plugin on port 55557 adds K2 node graph manipulation, faster bulk operations, and editor UI integration. Falls back to Python automatically when unavailable.

Configuration

Three-layer priority: CLI args > environment variables > config file > defaults.

Environment Variables

Variable	Default	Description
UNREAL_MCP_PROJECT_PATH	—	Path to .uproject file or project directory
UNREAL_MCP_ENGINE_PATH	auto-detect	UE engine install path
UNREAL_MCP_RC_PORT	30010	Remote Control API port
UNREAL_MCP_PYTHON_PORT	6776	Python Remote Execution port
UNREAL_MCP_PLATFORM	Win64	Target platform
UNREAL_MCP_CONFIGURATION	Development	Build configuration
UNREAL_MCP_MODULES	all	Comma-separated list of modules to enable

CLI Arguments

node dist/bin.js --project-path /path/to/project --engine-path /path/to/UE_5.5 --rc-port 30010

Config File

Place .unrealmcp.json in your project directory or home directory:

{
  "projectPath": ".",
  "platform": "Win64",
  "configuration": "Development",
  "enabledModules": ["console", "actor", "asset", "build", "blueprint", "material"]
}

Unreal Editor Setup

Required (for most tools)

1. Edit > Plugins > enable Python Editor Script Plugin
2. Restart the editor
3. Edit > Project Settings > Plugins > Python > scroll to Remote Execution section:
   • Check Enable Remote Execution
   • UE 5.3+ IMPORTANT: Change Multicast Bind Address from 127.0.0.1 to 0.0.0.0 — Epic changed the default in 5.3 and it breaks external tools
   • Verify Multicast Group Endpoint is 239.0.0.1:6766
4. Restart the editor again

Still getting "No Unreal Editor nodes found"?

• VPN/Tailscale users: Tailscale's virtual network adapter can hijack multicast. Try temporarily disabling Tailscale, or disable the Tailscale network adapter in Windows Network Connections.
• Firewall: Allow UDP port 6766 and TCP port 6776, or temporarily disable Windows Firewall to test.
• Multiple adapters: WSL, Hyper-V, and VPN adapters can all cause multicast to bind to the wrong interface. Disabling unused adapters helps.

Optional (for Remote Control tools)

1. Edit > Plugins > enable Remote Control API
2. Restart the editor
3. Edit > Project Settings > Plugins > Remote Control > Server:
   • Check Restrict Server Access — this sounds restrictive but actually enables the sub-options below (unchecked = features hidden/off)
   • Check Enable Remote Python Execution
   • Check Allow Console Command Remote Execution
   • Allowed Origins: leave blank or add 127.0.0.1
   • These take effect immediately, no restart needed

Optional (for Blueprint graph tools)

Install the C++ plugin from plugin/UnrealMCPBridge/ into your project's Plugins/ directory. This enables add_graph_node, connect_graph_nodes, and remove_graph_node.

Development

npm run dev        # Watch-mode dev server
npm run build      # Compile TypeScript
npm run lint       # Biome linter
npm run fmt        # Biome formatter
npm test           # Run tests

License

MIT