spring-boot-starter-swagger-mcp

Spring Boot starter that automatically exposes SpringDoc OpenAPI operations as MCP tools.

What You Get

• Auto-discovery of OpenAPI operations from your running Spring app
• Auto-registration of MCP tools for discovered API operations
• Smart-context tools: meta_discover_api_tools, meta_invoke_api_by_intent
• Response optimization with projection/summarization controls
• Risk controls for dangerous operations (_confirm, blocked paths, role checks, audit logs)

Architecture

graph TD
    User([User / LLM Client]) <--> MCP[MCP Client / Claude Desktop]
    MCP <--> Bridge[Swagger MCP Bridge /starter/]
    Bridge <--> Docs[SpringDoc OpenAPI /v3/api-docs]
    Bridge <--> API[Your Spring Controller /hello]

Quick Start (New Empty Spring Boot Project)

1. Create a Spring Boot app

Use:

• Java 17+
• Spring Boot 3.5.x
• Spring Web

2. Add dependencies

Gradle (build.gradle.kts):

plugins {
    id("org.springframework.boot") version "3.5.9"
    id("io.spring.dependency-management") version "1.1.7"
    java
}

java {
    sourceCompatibility = JavaVersion.VERSION_17
}

repositories {
    mavenCentral()
}

dependencies {
    implementation("org.springframework.boot:spring-boot-starter-web")
    implementation("org.springdoc:springdoc-openapi-starter-webmvc-api:2.8.3")
    implementation("io.github.neo1228:spring-boot-starter-swagger-mcp:<version>")
}

Maven (pom.xml):

<properties>
  <swagger-mcp.version>0.1.0-SNAPSHOT</swagger-mcp.version>
</properties>

<dependencies>
  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
  </dependency>
  <dependency>
    <groupId>org.springdoc</groupId>
    <artifactId>springdoc-openapi-starter-webmvc-api</artifactId>
    <version>2.8.3</version>
  </dependency>
  <dependency>
    <groupId>io.github.neo1228</groupId>
    <artifactId>spring-boot-starter-swagger-mcp</artifactId>
    <version>${swagger-mcp.version}</version>
  </dependency>
</dependencies>

Use a release version (for example 0.1.0) when consuming from a remote artifact repository.

3. Add one controller

import io.swagger.v3.oas.annotations.Operation;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.Map;

@RestController
public class HelloController {

    @Operation(operationId = "getHello", summary = "Get greeting message")
    @GetMapping("/hello")
    public Map<String, Object> hello(@RequestParam(defaultValue = "world") String name) {
        return Map.of("message", "Hello " + name);
    }
}

4. Add configuration (application.yml)

spring:
  ai:
    mcp:
      server:
        protocol: STREAMABLE_HTTP
        streamable-http:
          mcp-endpoint: /mcp

swagger:
  mcp:
    enabled: true
    api-docs-path: /v3/api-docs
    tool-name-prefix: api_

5. Run and verify

1. Start app: ./gradlew bootRun or ./mvnw spring-boot:run
2. Verify OpenAPI: http://localhost:8080/v3/api-docs
3. Verify MCP endpoint: http://localhost:8080/mcp
4. Connect from an MCP client

Generated tool names follow <tool-name-prefix><operation-id> (example: api_gethello).

Use It Before Public Release (Local Development Install)

If the artifact is not published to a remote registry yet:

1. Build and publish to local Maven cache:
   • ./gradlew publishToMavenLocal
2. In your consumer app:
   • add mavenLocal() repository
   • use version 0.1.0-SNAPSHOT (or your chosen local version)

Key Configuration

• swagger.mcp.enabled: enable/disable bridge (default true)
• swagger.mcp.api-docs-path: OpenAPI docs path (default /v3/api-docs)
• swagger.mcp.tool-name-prefix: tool name prefix (default api_)
• swagger.mcp.smart-context.gateway-only: expose only meta tools
• swagger.mcp.security.require-confirmation-for-risky-operations: require _confirm token for risky methods

For risky HTTP methods (POST, PUT, PATCH, DELETE), default policy requires _confirm=CONFIRM.

Compatibility Matrix

Starter	Java	Spring Boot	springdoc-openapi	Spring AI BOM
0.1.x	17+	3.5.x	2.8.3	1.1.2

Spring Boot 4.x is not supported in this repository.

Example Consumer Project

See examples/minimal-webmvc-gradle for a minimal app using this starter.

Release And Versioning

• Release process: RELEASING.md
• Versioning policy: VERSIONING.md
• Changelog: CHANGELOG.md

Development

• Run tests: ./gradlew test
• Contribution guide: CONTRIBUTING.md
• Security reporting: SECURITY.md

License

Apache License 2.0 (LICENSE)