The article discusses “Schema-Driven Development,” a methodology where API documentation is defined as an OpenAPI schema, enabling automatic generation of server and client code. In Spring WebMVC/WebFlux, springdoc-openapi can generate an OpenAPI schema from Spring controller implementations, facilitating automatic HTML documentation and client code generation. By defining controllers using interfaces since Spring 5.1, developers can achieve schema-driven development with less overhead, allowing for clearer separation of Swagger annotations and implementation code within controllers. The article also mentions the use of HTTP Interface Client in Spring 6 for building API clients easily in Spring environments.