uMCP

uMCP is a server implementation of the MCP protocol designed to work directly with Unity-based AI integrations. It communicates with MCP clients using the Streamable HTTP protocol, allowing a lightweight, dependency-free interaction path between your AI agents in Unity and external tooling. The server emphasizes safety by restricting operations to pre-authorized commands, ensuring that AI agents cannot execute arbitrary code. You can extend the server by adding your own custom commands and operations via the provided McpServerToolType and McpServerTool attributes, enabling bespoke interactions within a controlled feature set. In practice, you would connect your MCP client (supporting Streamable HTTP, such as VSCode Agent Mode, Cursor, or CLINE) to the uMCP server and begin exchanging MCP requests and responses to drive Unity-side behaviors. The README notes that the server can be extended with examples located under Assets/NatsunekoLaboratory/ModelContextProtocol/ManagementTools, serving as templates for new commands.

To use it, configure your MCP client to point at the server’s URL (for example http://localhost:7225/mcp or the SSE endpoint at http://localhost:7225/sse), then start your Unity project with the MCP server component active. Your client will be able to send and receive MCP operations, enabling coordinated AI interactions within Unity without requiring external runtimes beyond the Unity environment itself.

Prerequisites

• Unity Editor: Version 2022.3 LTS or newer
• The MCP client must support Streamable HTTP (examples include VSCode Agent Mode, Cursor, CLINE, etc.)

Install CoreFramework Option A: Unity Package Manager

1. Open your Unity project.
2. Run: openupm add com.natsuneko.modelcontextprotocol.core-framework
3. Restart and open the project to initialize the MCP Core Framework.

Option B: Git URL

1. Open your Unity project.
2. Go to Window > Package Manager.
3. Click the + button and choose Add package from git URL...
4. Enter the URL: https://github.com/mika-f/uMCP.git?path=/Assets/NatsunekoLaboratory/ModelContextProtocol/CoreFramework
5. Click Add. The MCP server automatically starts when you run the Unity project.

Install Management Tools (and other packages) Option A: Unity Package Manager

• openupm add com.natsuneko.modelcontextprotocol.management-tools
• openupm add com.natsuneko.modelcontextprotocol.vrchat-world-tools

Option B: Git URL

1. Open your Unity project.
2. Go to Window > Package Manager.
3. Click + and choose Add package from git URL...
4. Enter the URL: https://github.com/mika-f/uMCP.git?path=/Assets/NatsunekoLaboratory/ModelContextProtocol/MagagementTools
5. Click Add. After adding, start your project to initialize the MCP tools.

Notes and tips:

• The server is designed to be lightweight and Unity-centric, avoiding external runtimes where possible. Ensure your Unity project has the required Core Framework and Management Tools packages installed for full MCP functionality.
• Since uMCP relies on the Streamable HTTP protocol, verify that your MCP client is configured to connect to the correct endpoints, typically /mcp or /sse on the host where Unity is running.
• The Tools extension mechanism allows you to add custom operations. Look into Assets/NatsunekoLaboratory/ModelContextProtocol/ManagementTools for examples and adapt them to your project needs.
• The installation steps include both Unity Package Manager and Git URL options to accommodate different development setups. If you encounter issues, ensure the project has internet access to fetch packages and that the Unity version is compatible with the Core Framework packages.
• If you plan to run this in a Dockerized or headless environment, you may need to adjust network bindings and ensure the Unity runtime components are accessible in that context.