Agent Skills: spring-boot-web-api

Spring Boot 4 REST API implementation patterns. Use when creating REST controllers, REST endpoints, request validation, exception handlers with ProblemDetail (RFC 9457), API versioning, content negotiation, WebFlux reactive endpoints, HTTP clients with @HttpExchange, JSON serialization with Jackson 3, error handling, or CORS configuration. Covers @RestController patterns, Bean Validation 3.1, global error handling, and declarative HTTP clients.