OpenAPI is a REST architecture documentation (YAML or JSON) standard that outlines API endpoints, and data models (JSON Schema) for one or more servers.
With this programming language agnostic API definition file, you can:
- Generate code across application tiers (front-end and back-end),
- use it as documentation for your developers or implementation partners,
- and validate input and output against its JSON Schema definition,
- and even run simple test execution cases using the Swagger UI generation capability (see this live demo).
OpenAPI is a powerful tool that can improve collaborative efforts and streamline development efforts between teams (internally and externally)