mcp-server-spring-java

# MCP Server using Spring Boot Java A Model Context Protocol (MCP) server implementation built with Spring Boot and Java 21. This project demonstrates how to create an MCP server that provides user management tools for AI assistants. ## Features - Implements MCP server functionality using Spring AI - Exposes user management tools via MCP - Synchronous communication mode - Support for Standard I/O and Server-Sent Events transports - Integrates with DummyJSON external API for user data ## Technologies - Java 21 - Spring Boot 3.4.3 - Spring AI (Model Context Protocol) - Project Lombok - Maven ## Getting Started ### Prerequisites - Java 21 or higher - Maven ### Installation 1. Clone the repository ```bash git clone https://github.com/yourusername/mcp-spring-java.git cd mcp-spring-java ``` 2. Build the project ```bash mvn clean package ``` 3. Run the application ```bash java -jar target/mcp-spring-java-0.0.1-SNAPSHOT.jar ``` ## Configuration The MCP server is configured in `application.yml`: - Server runs on port 8090 - Server name: my-dummy-users-server - Synchronous communication mode - Supports STDIO transport for terminal-based communication - Exposes `/mcp/message` endpoint for SSE communication ## Available Tools The server exposes the following user management tools: - `getAllUsers` - Get all users with pagination - `getAllUsersDefault` - Get all users with default pagination - `getUserById` - Get a single user by ID - `searchUsers` - Search for users by query - `addUser` - Add a new user - `updateUser` - Update a user - `deleteUser` - Delete a user ## Testing with Postman You can use Postman to test the MCP server endpoints: 1. Start the MCP server 2. Open Postman and create a new request: - Method: POST - URL: http://localhost:8090/mcp/message - Headers: - Content-Type: application/json - Accept: application/json 3. For the request body, use the following JSON format to invoke any of the available tools: ```json { "message": { "toolCalls": [ { "id": "call-123", "name": "[TOOL_NAME]", "parameters": { "[PARAMETER_NAME]": "[PARAMETER_VALUE]" } } ] } } ``` ### Example Requests #### Get All Users (Default Pagination) ```json { "message": { "toolCalls": [ { "id": "call-123", "name": "getAllUsersDefault", "parameters": {} } ] } } ``` #### Get User by ID ```json { "message": { "toolCalls": [ { "id": "call-123", "name": "getUserById", "parameters": { "id": 1 } } ] } } ``` #### Search Users ```json { "message": { "toolCalls": [ { "id": "call-123", "name": "searchUsers", "parameters": { "query": "John" } } ] } } ``` The response will contain a JSON object with the results from the tool execution. ## Usage with MCP Clients You can configure this server in MCP client applications using the following configuration: ```json { "mcpServers": { "dummy-user-server": { "command": "java", "args": [ "-Dspring.ai.mcp.server.stdio=true", "-Dspring.main.web-application-type=none", "-Dlogging.pattern.console=", "-jar", "path/to/mcp-spring-java-0.0.1-SNAPSHOT.jar" ] } } } ``` ## License This project is licensed under the terms provided in the LICENSE file.