MCP Mediator – Automatic MCP Server Generation

What is MCP Mediator – Automatic MCP Server Generation?

MCP Mediator is a Java-based implementation of the Model Context Protocol (MCP) that automatically generates an MCP Server from existing source code, service classes, helper methods, and external MCP tools. It aggregates these diverse components into a unified MCP Server, streamlining communication between MCP clients and servers through a single point. It is designed for developers who want to make existing Java codebases MCP-compatible without altering the original code or tools.

How to use MCP Mediator – Automatic MCP Server Generation?

Prerequisites: Java 17+, Maven 3.6+, and Spring Boot 3.2.2+ (for Spring integration). To use, instantiate a DefaultMcpMediator with a configuration builder, register request handlers (or convert existing classes using @McpService and McpServiceFactory), then call initialize(). For proxying, use ProxyMcpMediator. Run examples via the provided run.sh script, e.g., ./run.sh DefaultMcpMediatorStdioExample, and configure as a Claude Desktop MCP Server in the claude_desktop_config.json.

Key features of MCP Mediator – Automatic MCP Server Generation

• Support for stdio and SSE transport
• Extensible request handling system
• Configurable server capabilities
• Support for multiple tool implementations
• Proxying multiple remote MCP servers
• Auto‑generates MCP Server Tools from existing methods and services
• Annotation‑based conversion (@McpService, @McpTool)

Use cases of MCP Mediator – Automatic MCP Server Generation

• Convert existing Java service classes into MCP tools without modifying the original code
• Create a unified proxy that aggregates several MCP servers under one endpoint
• Enable MCP clients (e.g., Claude Desktop) to invoke existing business logic via STDIO or SSE
• Integrate MCP capabilities into Spring Boot applications
• Provide MCP access to external query sources like Wikipedia, StackOverflow, and GitHub

FAQ from MCP Mediator – Automatic MCP Server Generation

What transports does MCP Mediator support?

It supports stdio (STDIO) and SSE (Server‑Sent Events) transport mechanisms.

What are the prerequisites for using MCP Mediator?

You need Java 17 or later, Maven 3.6 or later, and optionally Spring Boot 3.2.2 or later for Spring/Spring Boot integration.

How do I convert an existing class into an MCP server?

Annotate methods with @McpTool and the class with @McpService, then use McpServiceFactory.create() to register the service as a handler with a DefaultMcpMediator.

Does MCP Mediator support Spring Boot?

Yes, Spring Framework and Spring Boot integration is available via the mcp-mediator-spring and mcp-mediator-spring-boot-starter modules (work in progress, as noted in the README).

Can MCP Mediator proxy multiple MCP servers?

Yes, the ProxyMcpMediator can connect to multiple remote STDIO MCP servers, advertise their tools, and optionally add local request handlers.