Code First API Design
Code First API Design is a development approach where developers write the implementation code first, and then generate API documentation, schemas, or client libraries automatically from that code. It contrasts with Design First approaches by prioritizing working software and iterative development over upfront specification. This methodology often leverages tools that inspect code annotations, types, or runtime behavior to produce OpenAPI/Swagger specifications or other API artifacts.
Developers should use Code First API Design when working in agile environments where requirements evolve rapidly, as it allows for faster iteration and reduces duplication between code and documentation. It's particularly useful for teams that prefer to prototype quickly or maintain a single source of truth in the codebase, avoiding the overhead of manually synchronizing specifications. Common use cases include building RESTful APIs in frameworks like ASP.NET Core, Spring Boot, or FastAPI, where annotations or decorators can drive documentation generation.