Model Context Protocol (MCP) Servers and Clients

<dependency>
    <groupId>org.springframework.ai</groupId>
    <artifactId>spring-ai-starter-mcp-server-webmvc</artifactId>
</dependency>

# application.yml
spring:
  ai:
    mcp:
      server:
        name: webnest-courses
        version: 1.0.0
        type: SYNC
        protocol: STREAMABLE
server:
  port: 8090

@Component
public class CourseCatalogTools {

    private final CourseRepository courses;

    public CourseCatalogTools(CourseRepository courses) {
        this.courses = courses;
    }

    @McpTool(name = "search_courses",
             description = "Search Webnest courses by keyword and return title, level and lesson count")
    public List<CourseSummary> searchCourses(
            @McpToolParam(description = "Keyword such as 'spring' or 'sql'", required = true) String keyword) {
        return courses.searchByKeyword(keyword).stream()
            .map(c -> new CourseSummary(c.getSlug(), c.getTitle(), c.getLevel(), c.getLessonCount()))
            .toList();
    }

    @McpTool(name = "course_outline", description = "Get the module and lesson outline of a course by slug")
    public CourseOutline outline(
            @McpToolParam(description = "Course slug, e.g. spring-boot", required = true) String slug) {
        return courses.outline(slug);
    }
}

public record CourseSummary(String slug, String title, String level, int lessons) {}

@Component
public class CourseResources {

    @McpResource(uri = "webnest://syllabus/{slug}", name = "Course syllabus",
                 description = "Markdown syllabus of a Webnest course")
    public String syllabus(String slug) {
        return syllabusService.markdownFor(slug);
    }

    @McpPrompt(name = "study_plan", description = "Create a weekly study plan for a course")
    public GetPromptResult studyPlan(
            @McpArg(name = "slug", description = "Course slug", required = true) String slug,
            @McpArg(name = "hoursPerWeek", description = "Available hours per week", required = true) String hours) {
        String text = "Create a week-by-week study plan for the course '" + slug
            + "' for a learner with " + hours + " hours per week.";
        return GetPromptResult.builder(List.of(new PromptMessage(Role.USER, TextContent.builder(text).build())))
            .description("Study plan")
            .build();
    }
}

<dependency>
    <groupId>org.springframework.ai</groupId>
    <artifactId>spring-ai-starter-mcp-client</artifactId>
</dependency>

# application.yml of the assistant app
spring:
  ai:
    mcp:
      client:
        type: SYNC
        request-timeout: 30s
        streamable-http:
          connections:
            courses:
              url: http://localhost:8090
              endpoint: /mcp
        stdio:
          connections:
            filesystem:
              command: npx
              args:
                - "-y"
                - "@modelcontextprotocol/server-filesystem"
                - "C:/webnest/notes"

@RestController
public class AdvisorController {

    private final ChatClient chatClient;

    public AdvisorController(ChatClient.Builder builder, SyncMcpToolCallbackProvider mcpTools) {
        this.chatClient = builder
            .defaultSystem("You are a course advisor for Webnest Studio.")
            .defaultTools(mcpTools.getToolCallbacks())
            .build();
    }

    @GetMapping("/advisor")
    public String advise(@RequestParam String goal) {
        return chatClient.prompt().user(goal).call().content();
    }
}

# Official MCP debugging UI (requires Node.js)
npx @modelcontextprotocol/inspector

# In the Inspector UI:
#   Transport: Streamable HTTP
#   URL:       http://localhost:8090/mcp
#   -> Connect -> Tools -> search_courses -> keyword = "spring" -> Run