Unreal Engine MCP Python Bridge Plugin

What is Unreal Engine MCP Python Bridge Plugin?

Unreal Engine MCP Python Bridge Plugin is an Unreal Engine plugin that implements the Model Context Protocol (MCP) server. It allows MCP clients, such as Anthropic’s Claude, to access the full Unreal Engine Python API, enabling AI-assisted development and automation within Unreal Engine projects.

How to use Unreal Engine MCP Python Bridge Plugin?

Install the plugin from the Fab store or build from source. After enabling the plugin in Unreal Engine, click the “Start MCP Bridge” toolbar button to start a socket server on 127.0.0.1:9000. Configure your MCP client (e.g., Claude) to use unreal_mcp_client.py as the server script, then attach the client to the running bridge.

Key features of Unreal Engine MCP Python Bridge Plugin

• Exposes the full Unreal Engine Python API to MCP clients.
• Includes sample tools and prompts (e.g., create_castle, create_town).
• Provides a client script (unreal_mcp_client.py) that communicates over sockets.
• Supports easy extension with custom Python tools and prompts.
• Works with any MCP‑compatible AI agent.
• Requires only the official MCP Python SDK as an external dependency.

Use cases of Unreal Engine MCP Python Bridge Plugin

• Developing Python tools and workflows with an agent like Claude.
• Intelligent and dynamic automation of Unreal Engine tasks.
• General collaborative development with an AI agent in Unreal Engine.

FAQ from Unreal Engine MCP Python Bridge Plugin

How do I add a new tool?

Add a new function decorated with @mcp.tool() in unreal_mcp_client.py that sends a command to Unreal Engine, and implement the corresponding server‑side method in unreal_server_init.py under the plugin’s Content folder. Restart Unreal Engine after server changes; restart Claude after client changes.

What are the system requirements?

Python 3.10 or higher must be available on the system PATH with the MCP Python SDK installed (pip install mcp). Unreal Engine 5 with Python Editor Script Plugin enabled is required. Visual Studio 2019+ is needed only if building from source.

Does the client script run inside Unreal Engine’s Python?

No. The unreal_mcp_client.py runs as a subprocess of your AI agent using the system Python. It communicates with Unreal Engine over a local socket.

How do I install the plugin?

The easiest way is from the Fab store. GitHub installation requires cloning into the Plugins folder of a C++ Unreal Engine project, generating Visual Studio project files, building, then enabling the plugin.

What transport and authentication does the server use?

The server uses a local TCP socket (127.0.0.1:9000). No authentication is mentioned; it is designed for local use by the AI agent.