EngineWire（原 Unreal MCP）

EngineWire

  EngineWire connects Claude, Cursor, VS Code or any other MCP client to a running Unreal Editor,
  and let it build levels, Blueprints, UI, materials, effects and more, through a native C++ editor plugin.

  🧭 One tool, over 400 capabilities  ·  ⚙️ Native C++ editor plugin  ·  🌐 HTTP or stdio  ·  🔐 Local and token-protected by default  ·  🎮 Unreal Engine 5.0 – 5.8

  🚀 Quick Start  · 
  📖 Wiki  · 
  📦 Releases  · 
  💬 Discussions

> 📌 Which version is this? This README describes the 0.6 line: the dev branch and npm unreal-engine-mcp-server@beta. The previous stable release, 0.5.30 (npm latest), exposes 23 separate tools instead of one; see Upgrading from 0.5.x.

Contents · What it does · How it works · Quick start · The unreal tool · Configuration · Security · Engine plugins · Docker · Documentation · Development · Community

What it does

🏗️ Levels and actors
Spawn one actor or hundreds in a single call, place and attach them, find the ones sunk into the floor, and load, stream and save levels.

🧩 Blueprints and UI
Create Blueprints, variables and components, build whole event graphs in one batch, and lay out UMG widgets, with a preview image to check them.

🎨 Materials and worlds
Material graphs and instances, procedural textures, lighting, landscapes, foliage, Niagara effects and PCG graphs.

🕹️ Gameplay
Characters and animation, Gameplay Ability System, AI (Behavior Trees, State Trees, EQS), inventory, networking and Enhanced Input.

🎬 Cinematics and audio
Level Sequences, cameras, Movie Render Queue and Take Recorder; Sound Cues and MetaSounds.

🧪 Play and verify
Run Play-In-Editor with synthetic input, take screenshots the model can see, read logs, profile, run Python, and package builds.

Nearly 400 capabilities in all, behind a single MCP tool. The assistant finds them by searching in plain words, so nobody has to learn their names. The full list is the generated Action Reference.

  A platformer level built with the MCP, in Unreal Editor 5.8. Bottom right: the plugin's status, MCP :3000 (1), meaning the native server is running on port 3000 with one client connected.

How it works

The EngineWire plugin runs inside the editor and does all the work, on the editor's game thread. Clients reach it in one of two ways, and both expose the same single tool, unreal:

| | 🌐 Route A · Native HTTP | 🧩 Route B · stdio |
| Path | Client → the plugin's Streamable HTTP server at http://127.0.0.1:3000/mcp | Client → unreal-engine-mcp-server (Node.js, stdio) → the plugin's WebSocket on 127.0.0.1:8090 |
| Node.js | Not needed | 20.19 or later |
| Capability token | The client sends it in the X-MCP-Capability-Token header | Read from the project, given UE_PROJECT_PATH |
| Best for | Claude Code, Cursor, VS Code, and several clients sharing one editor | Claude Desktop, and clients that only launch local commands |

Everything listens on 127.0.0.1 and requires the project's capability token unless you change it.

Quick start

The Quick Start page walks through this with screenshots. You need Unreal Engine 5.0 to 5.8 and a project with C++ code; a Blueprint

……（后略，见原文）