Configuration

Configuration

Environment variables and settings for Unreal MCP.

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Quick Reference

You only need one setting to get started:

{
  "UE_PROJECT_PATH": "C:/Path/To/YourProject"
}

Everything else has sensible defaults.

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Required Settings

Setting	Description	Example
UE_PROJECT_PATH	Path to your Unreal project folder	C:/Projects/MyGame

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Complete MCP Config

Copy-paste this into your MCP config file:

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

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Optional Settings

Only change these if you have specific needs:

Setting	Default	Description
MCP_AUTOMATION_PORT	8091	Change if port 8091 is already in use
LOG_LEVEL	info	Set to debug for troubleshooting
WASM_ENABLED	true	Set to false to disable WebAssembly

Example with Optional Settings

{
  "mcpServers": {
    "unreal-engine": {
      "command": "npx",
      "args": ["unreal-engine-mcp-server"],
      "env": {
        "UE_PROJECT_PATH": "C:/Projects/MyGame",
        "MCP_AUTOMATION_PORT": "8091",
        "LOG_LEVEL": "info",
        "WASM_ENABLED": "true"
      }
    }
  }
}

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All Settings Reference

Setting	Default	Description
UE_PROJECT_PATH	(required)	Your Unreal project folder path
MCP_AUTOMATION_HOST	127.0.0.1	WebSocket host address
MCP_AUTOMATION_PORT	8091	WebSocket port
MCP_AUTOMATION_REQUEST_TIMEOUT_MS	120000	Request timeout in milliseconds
MCP_AUTOMATION_ALLOW_NON_LOOPBACK	false	Enable for LAN access
LOG_LEVEL	info	debug, info, warn, or error
WASM_ENABLED	true	WebAssembly acceleration
ASSET_LIST_TTL_MS	10000	Asset list cache duration
MOCK_UNREAL_CONNECTION	false	For testing without Unreal

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Config File Locations

AI Client	Config File
Claude Desktop (Windows)	%APPDATA%/Claude/claude_desktop_config.json
Claude Desktop (Mac)	~/Library/Application Support/Claude/claude_desktop_config.json
Cursor	~/.cursor/mcp.json
Windsurf	~/.config/windsurf/mcp.json

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LAN Access (Optional)

To access from other machines on your network:

{
  "mcpServers": {
    "unreal-engine": {
      "command": "npx",
      "args": ["unreal-engine-mcp-server"],
      "env": {
        "UE_PROJECT_PATH": "C:/Projects/MyGame",
        "MCP_AUTOMATION_ALLOW_NON_LOOPBACK": "true",
        "MCP_AUTOMATION_HOST": "0.0.0.0"
      }
    }
  }
}

Warning: Only enable on trusted networks. This exposes the automation bridge to your LAN.

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See Also

• Quick Start - Get started fast
• Installation - Full setup guide
• Troubleshooting - Common issues