api2mcp4j

Overview

api2mcp4j is an innovative Spring Boot extension that enables developers to expose existing REST APIs as MCP tools without extensive code changes. The project automatically scans @RestController and @Service beans, leveraging information from Swagger/OpenAPI, Javadoc, and Spring MVC metadata to generate MCP tool definitions. This non-intrusive approach allows for quick integration of AI capabilities into existing Java applications while maintaining business logic integrity. The project supports custom annotations for fine-grained control and is compatible with the latest MCP Java SDK features including callbacks, resources, and prompts.

Try asking AI

After installing, here are 6 things you can ask your AI assistant:

• auto-discover_controllersvoid discoverControllers()

  Automatically scans and registers all controller methods as MCP tools

  Try:Automatically scan my REST controllers for MCP toolsTry:Discover all available endpoints in my application
• parse_swaggervoid parseSwagger(String apiPath)

  Parse Swagger/OpenAPI documentation to generate MCP tool descriptions

  Try:Use my Swagger documentation to create tool descriptionsTry:Parse my OpenAPI spec for better tool metadata
• parse_javadocvoid parseJavadoc(String sourcePath)

  Extract Java documentation comments for tool descriptions

  Try:Use Javadoc comments to describe my toolsTry:Generate tool descriptions from source code comments
• configure_mcp_servervoid configureMcpServer(Config config)

  Configure MCP server with custom settings and parser combinations

  Try:Configure my MCP server to use multiple parsersTry:Set up auto-discovery for all my REST endpoints

Note: Tool names were inferred from the features described in the README, as actual tool names weren't explicitly listed. The server exposes automatic discovery and parsing capabilities rather than specific named tools.

Comparable tools

Installation

git clone https://github.com/TheEterna/api2mcp4j.git
cd api2mcp4j/server2mcp-starter-webmvc
mvn clean install

<dependency>
    <groupId>com.ai.plug</groupId>
    <artifactId>server2mcp-starter-webmvc</artifactId>
    <version>1.1.4-SNAPSHOT</version>
</dependency>

plugin:
  mcp:
    enabled: true
    parser:
      params: SWAGGER3, SWAGGER2, SpringMVC, JACKSON, TOOL
      des:    SWAGGER3, SWAGGER2, JAVADOC, TOOL, JACKSON
    scope: interface

FAQ

What is the main advantage of api2mcp4j over traditional MCP implementations?

The main advantage is zero to low code integration - it automatically converts existing REST APIs to MCP tools without requiring manual @Tool annotations or code refactoring.

Does api2mcp4j support all Spring Boot versions?

api2mcp4j is designed for Spring Boot 3.x and requires Java 17 or higher for compatibility.

Can I combine multiple parsers for better tool descriptions?

Yes, the project supports combining multiple parsers including Swagger/OpenAPI, Javadoc, Spring MVC metadata, Jackson, and custom annotations for comprehensive tool descriptions.

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