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Unreal Engine MCP Server

License: MIT NPM Package MCP SDK Unreal Engine MCP Registry Project Board Discussions

A comprehensive Model Context Protocol (MCP) server that enables AI assistants to control Unreal Engine through a native C++ Automation Bridge plugin. Built with TypeScript and C++.


Table of Contents


Features

Category Capabilities
Asset Management Browse, import, duplicate, rename, delete assets; create materials
Actor Control Spawn, delete, transform, physics, tags, components
Editor Control PIE sessions, camera, viewport, screenshots, bookmarks
Level Management Load/save levels, streaming, World Partition, data layers
Animation & Physics Animation BPs, state machines, ragdolls, vehicles, constraints
Visual Effects Niagara particles, GPU simulations, procedural effects, debug shapes
Sequencer Cinematics, timeline control, camera animations, keyframes
Graph Editing Blueprint, Niagara, Material, and Behavior Tree graph manipulation
Audio Sound cues, audio components, sound mixes, ambient sounds
System Console commands, UBT, tests, logs, project settings, CVars

Architecture

  • Native C++ Automation — All operations route through the MCP Automation Bridge plugin
  • Dynamic Type Discovery — Runtime introspection for lights, debug shapes, and sequencer tracks
  • Graceful Degradation — Server starts even without an active Unreal connection
  • On-Demand Connection — Retries automation handshakes with exponential backoff
  • Command Safety — Blocks dangerous console commands with pattern-based validation
  • Asset Caching — 10-second TTL for improved performance
  • Metrics Rate Limiting — Per-IP rate limiting (60 req/min) on Prometheus endpoint
  • Centralized Configuration — Unified class aliases and type definitions

Getting Started

Prerequisites

  • Node.js 18+
  • Unreal Engine 5.0–5.7

Step 1: Install MCP Server

Option A: NPX (Recommended)

npx unreal-engine-mcp-server

Option B: Clone & Build

git clone https://github.com/ChiR24/Unreal_mcp.git
cd Unreal_mcp
npm install
npm run build
node dist/cli.js

Step 2: Install Unreal Plugin

The MCP Automation Bridge plugin is included at Unreal_mcp/plugins/McpAutomationBridge.

Method 1: Copy Folder

Copy:  Unreal_mcp/plugins/McpAutomationBridge/
To:    YourUnrealProject/Plugins/McpAutomationBridge/

Regenerate project files after copying.

Method 2: Add in Editor

  1. Open Unreal Editor → Edit → Plugins
  2. Click "Add" → Browse to Unreal_mcp/plugins/
  3. Select the McpAutomationBridge folder

Video Guide:

Plugin_setup_guide.mp4

⚠️ First-Time Project Open: When opening the project directly (double-click .uproject) for the first time, UE will prompt "Would you like to rebuild them now?" for missing modules. Click Yes to rebuild. After the rebuild completes, you may still see: "Plugin 'McpAutomationBridge' failed to load because module could not be loaded." This is expected — UE rebuilds successfully but doesn't reload the plugin in the same session. Simply close and reopen the project and the plugin will load correctly. Alternatively, build via Visual Studio first to avoid this.

Step 3: Enable Required Plugins

Enable via Edit → Plugins, then restart the editor.

Core Plugins (Required)
Plugin Required For
MCP Automation Bridge All automation operations
Editor Scripting Utilities Asset/Actor subsystem operations
Niagara Visual effects and particle systems
Optional Plugins (Auto-enabled)
Plugin Required For
Level Sequence Editor manage_sequence operations
Control Rig animation_physics operations
GeometryScripting manage_geometry operations
Behavior Tree Editor manage_behavior_tree operations
Niagara Editor Niagara authoring
Environment Query Editor AI/EQS operations
Gameplay Abilities manage_gas operations
MetaSound manage_audio MetaSound authoring
StateTree manage_ai State Tree operations
Smart Objects AI smart object operations
Enhanced Input manage_input operations
Chaos Cloth Cloth simulation
Interchange Asset import/export
Data Validation Data validation
Procedural Mesh Component Procedural geometry
OnlineSubsystem Session/networking operations
OnlineSubsystemUtils Session/networking operations

💡 Optional plugins are auto-enabled by the MCP Automation Bridge plugin when needed.

Step 4: Configure MCP Client

Add to your Claude Desktop / Cursor config file:

Using Clone/Build:

{
  "mcpServers": {
    "unreal-engine": {
      "command": "node",
      "args": ["path/to/Unreal_mcp/dist/cli.js"],
      "env": {
        "UE_PROJECT_PATH": "C:/Path/To/YourProject",
        "MCP_AUTOMATION_PORT": "8091"
      }
    }
  }
}

Using NPX:

{
  "mcpServers": {
    "unreal-engine": {
      "command": "npx",
      "args": ["unreal-engine-mcp-server"],
      "env": {
        "UE_PROJECT_PATH": "C:/Path/To/YourProject"
      }
    }
  }
}

Configuration

Environment Variables

# Required
UE_PROJECT_PATH="C:/Path/To/YourProject"

# Automation Bridge
MCP_AUTOMATION_HOST=127.0.0.1
MCP_AUTOMATION_PORT=8091

# LAN Access (optional)
# SECURITY: Set to true to allow binding to non-loopback addresses (e.g., 0.0.0.0)
# Only enable if you understand the security implications.
MCP_AUTOMATION_ALLOW_NON_LOOPBACK=false

# Logging
LOG_LEVEL=info  # debug | info | warn | error

# Optional
MCP_AUTOMATION_REQUEST_TIMEOUT_MS=120000
ASSET_LIST_TTL_MS=10000

LAN Access Configuration

By default, the automation bridge only binds to loopback addresses (127.0.0.1) for security. To enable access from other machines on your network:

TypeScript (MCP Server):

MCP_AUTOMATION_ALLOW_NON_LOOPBACK=true
MCP_AUTOMATION_HOST=0.0.0.0

Unreal Engine Plugin:

  1. Go to Edit → Project Settings → Plugins → MCP Automation Bridge
  2. Under Security, enable "Allow Non Loopback"
  3. Under Connection, set "Listen Host" to 0.0.0.0
  4. Restart the editor

⚠️ Security Warning: Enabling LAN access exposes the automation bridge to your local network. Only use on trusted networks with appropriate firewall rules.


Available Tools

36 MCP tools with action-based dispatch for comprehensive Unreal Engine automation.

Core Tools
Tool Description
manage_asset Assets, Materials, Render Targets, Behavior Trees
control_actor Spawn, delete, transform, physics, tags
control_editor PIE, Camera, viewport, screenshots
manage_level Load/Save, World Partition, streaming
system_control UBT, Tests, Logs, Project Settings, CVars
inspect Object Introspection
manage_pipeline Build automation, UBT compilation, status checks
manage_tools Dynamic tool management (enable/disable at runtime)
World Building
Tool Description
manage_lighting Spawn lights, GI, shadows, build lighting, list_light_types
manage_level_structure Level creation, sublevels, World Partition, data layers, HLOD
manage_volumes Trigger volumes, blocking, physics, audio, navigation volumes
manage_navigation NavMesh settings, nav modifiers, nav links, smart links, pathfinding
build_environment Landscape, Foliage, Procedural
manage_splines Spline creation, spline mesh deformation
Animation & Physics
Tool Description
animation_physics Animation BPs, Vehicles, Ragdolls, Control Rig, IK, Blend Spaces
manage_skeleton Skeleton, sockets, physics assets, cloth binding
manage_geometry Procedural mesh creation (Geometry Script)
Visuals & Effects
Tool Description
manage_effect Niagara, Particles, Debug Shapes, GPU simulations
manage_material_authoring Material creation, expressions, landscape layers
manage_texture Texture creation, modification, compression settings
manage_blueprint Create, SCS, Graph Editing, Node manipulation
manage_sequence Sequencer / Cinematics, list_track_types
manage_performance Profiling, optimization, scalability
Audio & Input
Tool Description
manage_audio Audio Assets, Components, Sound Cues, MetaSounds, Attenuation
manage_input Enhanced Input Actions & Contexts
Gameplay Systems
Tool Description
manage_behavior_tree Behavior Tree Graph Editing
manage_ai AI controllers, EQS, perception, State Trees, Smart Objects
manage_gas Gameplay Ability System: abilities, effects, attributes
manage_character Character creation, movement, advanced locomotion
manage_combat Weapons, projectiles, damage, melee combat
manage_inventory Items, equipment, loot tables, crafting
manage_interaction Interactables, destructibles, triggers
manage_widget_authoring UMG widget creation, layout, styling, animations
Networking & Sessions
Tool Description
manage_networking Replication, RPCs, network prediction
manage_game_framework Game modes, game states, player controllers, match flow
manage_sessions Sessions, split-screen, LAN, voice chat
### Supported Asset Types

Blueprints • Materials • Textures • Static Meshes • Skeletal Meshes • Levels • Sounds • Particles • Niagara Systems • Behavior Trees


Optional GraphQL endpoint for complex queries. Disabled by default.

GRAPHQL_ENABLED=true
GRAPHQL_PORT=4000

See GraphQL API Documentation.


Docker

docker build -t unreal-mcp .
docker run -it --rm -e UE_PROJECT_PATH=/project unreal-mcp

Documentation

Document Description
Handler Mappings TypeScript to C++ routing
GraphQL API Query and mutation reference
Plugin Extension C++ plugin architecture
Testing Guide How to run and write tests
Roadmap Development phases

Development

npm run build       # Build TypeScript
npm run lint        # Run ESLint
npm run test:unit   # Run unit tests
npm run test:all    # Run all tests

Community

Resource Description
Project Roadmap Track development progress across 47 phases
Discussions Ask questions, share ideas, get help
Issues Report bugs and request features

Contributing

Contributions welcome! Please:

  • Include reproduction steps for bugs
  • Keep PRs focused and small
  • Follow existing code style

License

MIT — See LICENSE

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A comprehensive Model Context Protocol (MCP) server that enables AI assistants to control Unreal Engine through the native C++ Automation Bridge plugin. Built with TypeScript and C++.

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  • C++ 69.4%
  • TypeScript 26.8%
  • C 1.9%
  • JavaScript 1.6%
  • Other 0.3%