Configuration
Configuration documentation.
MCP Client Configuration
The easiest way to configure UE-MCP is to run npx ue-mcp init — it detects your MCP clients and writes the config automatically.
Manual Configuration
{
"mcpServers": {
"ue-mcp": {
"command": "npx",
"args": ["ue-mcp", "C:/path/to/MyGame.uproject"]
}
}
}Where to Put This
| Client | Config File |
|---|---|
| Claude Code | .mcp.json in project root, or ~/.claude/ global config |
| Claude Desktop | claude_desktop_config.json |
| Cursor | mcp.json in .cursor/ or project root |
Without a Project Path
You can start the server without a .uproject argument. It will run in a limited mode — you can then use project(action="set_project", projectPath="...") at runtime to attach to a project.
Project Configuration (.ue-mcp.json)
Place a .ue-mcp.json file in your UE project root (next to the .uproject) to customize behavior. npx ue-mcp init creates this for you.
{
"contentRoots": ["/Game/", "/MyPlugin/"],
"disable": ["gas", "networking"]
}Options
| Key | Type | Default | Description |
|---|---|---|---|
contentRoots | string[] | ["/Game/"] | Content paths to search when using asset(action="search"). Add plugin content roots here if your project uses plugins with their own assets. |
disable | string[] | [] | Tool categories to disable. Disabled categories are not registered with the MCP server, reducing context noise for the AI. |
Bridge Connection
The C++ plugin listens on ws://localhost:9877 (currently hardcoded). The MCP server auto-connects on startup and reconnects every 15 seconds if the connection drops.
Connection States
| State | Meaning |
|---|---|
| Connected | Bridge is active, all tools available |
| Disconnected | Editor not running or plugin not loaded. Filesystem tools still work (INI parsing, C++ headers, asset listing) |
| Reconnecting | Connection lost, auto-retry in progress |
Check the current state with project(action="get_status").
Plugin Deployment
On first run with a project path, the server automatically:
- Copies
plugin/ue_mcp_bridge/→[Project]/Plugins/UE_MCP_Bridge/ - Adds
UE_MCP_Bridgeto the.uprojectplugins list - Enables
PythonScriptPluginif not already enabled (needed forexecute_pythonescape hatch)
The plugin is editor-only and has no runtime footprint.
Plugin Dependencies
The C++ bridge plugin enables these UE plugins (adding them to .uproject if missing):
PythonScriptPlugin— foreditor(action="execute_python")EnhancedInput— for input action/mapping creationGameplayAbilities— for GAS toolsNiagara— for VFX toolsPCG— for procedural generation tools
Editor Lifecycle
The server can manage the editor process:
| Command | Description |
|---|---|
editor(action="start_editor") | Launch UE with the current project |
editor(action="stop_editor") | Gracefully stop the editor |
editor(action="restart_editor") | Stop and relaunch |