SpringBoot MCP Server with JUnit

Overview

The SpringBoot MCP + JUnit template is a ready‑to‑run foundation for building Model Context Protocol (MCP) servers with Spring Boot. It streamlines the process of exposing AI‑ready services that can be consumed by Claude or other MCP‑compatible assistants, while also providing a robust unit‑testing layer through JUnit. By integrating Spring’s mature ecosystem with MCP, developers can focus on business logic rather than protocol plumbing.

Problem Solved

Developers building AI assistants often need a lightweight, standards‑compliant server that can accept and respond to MCP messages. Setting up such a server from scratch involves configuring protocol endpoints, handling encoding nuances, and ensuring compatibility with both STDIO and Server‑Sent Events (SSE) clients. The template eliminates this boilerplate, offering a pre‑configured SpringBoot application that supports both STDIO and SSE modes out of the box. It also includes a JUnit testing harness, allowing rapid verification of MCP interactions without manual HTTP or socket traffic.

Core Value

• Rapid Prototyping – The project skeleton contains all necessary dependencies and configuration files, enabling developers to spin up an MCP server in minutes.
• Dual‑Mode Operation – By toggling a single JVM property (), the same binary can serve as an STDIO or SSE endpoint, making it versatile for local debugging and production deployment.
• Encoding Awareness – The template forces UTF‑8 on /, preventing common character‑encoding bugs when exchanging JSON payloads with AI assistants.
• Extensible Endpoints – Through developers can easily re‑route message or SSE paths, and even inject custom transports for advanced scenarios such as multi‑endpoint services.

Real‑World Use Cases

• Local Development & Testing – A data scientist can run the server locally, feeding it through a terminal or a lightweight SSE client, and immediately see how an AI assistant interprets prompts.
• CI/CD Integration – The included JUnit tests can be executed in continuous‑integration pipelines to ensure that MCP endpoints behave correctly after code changes.
• Microservice Integration – The server can be embedded in larger Spring applications, exposing AI‑enabled services (e.g., summarization, translation) that other components can call via MCP.
• Rapid MVPs – Start a minimum viable product with an AI assistant backend without wrestling with low‑level protocol details, then scale to production by adding authentication or load balancing.

Integration with AI Workflows

Once the server is running, an MCP‑compatible assistant simply sends a JSON payload to either (via the JVM’s standard streams) or to an SSE endpoint (). The server processes the request, applies any business logic, and streams back responses in real time. Because the template follows the official MCP specification, it guarantees interoperability with any future MCP clients or extensions.

Standout Advantages

• SpringBoot + MCP Synergy – Leverages Spring’s dependency injection, configuration properties, and actuator endpoints for seamless monitoring.
• JUnit‑Ready – Built‑in test support removes the need to write custom integration tests for MCP traffic.
• Future‑Proofing – The template references the latest MCP specification and anticipates upcoming authentication features, ensuring longevity.

In summary, this SpringBoot MCP + JUnit template empowers developers to deploy robust, standards‑compliant AI assistant backends quickly while maintaining testability and configurability across diverse deployment scenarios.