jooby-mcp

This module provides a lightweight wrapper around the official Java MCP SDK, adapted for use with Jooby’s routing, server capabilities and DI.

Unlike some other frameworks, this module does not (yet) offer convenient annotations. Instead, it delivers a minimal abstraction over the official MCP SDK to help structure your code more effectively.

Additionally, it supports running multiple MCP servers within a single Jooby instance.

Usage

1. Add the dependency to your pom.xml:

   <dependency>
       <groupId>io.github.kliushnichenko</groupId>
       <artifactId>jooby-mcp</artifactId>
       <version>${version}</version>
   </dependency>

2. Add configuration to application.conf

   mcp {
     name: "my-awesome-mcp-server"     # Required
     version: "0.0.1"                  # Required
     sseEndpoint: "/mcp/sse"           # Optional (default: /mcp/sse)
     messageEndpoint: "/mcp/message"   # Optional (default: /mcp/message)
   }
   

3. Implement your tool, prompt or resource, see examples below

4. Install module and register your tools, prompts, resources in the application

   {
        install(AvajeInjectModule.of()); // or other DI module of your choice, should go before McpModule
        install(new McpModule()
            .tools(Set.of(GetWeatherTool.class))
            .prompts(Set.of(MyAwesomePrompt.class))
        );
   }

Example Tool

import io.github.kliushnichenko.jooby.mcp.McpSyncTool;

@Singleton
public class GetWeatherTool implements McpSyncTool {

  @Inject
  private final WeatherService weatherService;

  @Override
  public McpSchema.Tool specification() {
      var schema = """
              {
                "type" : "object",
                "id" : "urn:jsonschema:Operation",
                "properties" : {
                  "latitude" : {
                    "type" : "number"
                  },
                  "longitude" : {
                    "type" : "number"
                  }
                }
              }
              """;

      return new McpSchema.Tool("get_weather",
              "Fetches weather by latitude and longitude coordinates",
              schema);
  }

  @Override
  public McpSchema.CallToolResult handler(McpSyncServerExchange exchange, Map<String, Object> args) {
      Double latitude = (Double) args.get("latitude");
      Double longitude = (Double) args.get("longitude");
      var weather = weatherService.getWeather(latitude, longitude);
      return new McpSchema.CallToolResult(weather, false);
  }
}