What is Swagger primarily used for?

Swagger is primarily used for designing and documenting APIs. It provides a powerful framework that enables developers to define their API structure in a clear and machine-readable format. This is often done using the OpenAPI Specification (formerly known as Swagger Specification). The main advantage of using Swagger for API documentation is that it allows for interactive documentation, where users can try out API calls directly from the documentation interface.

Additionally, as APIs evolve, Swagger helps keep the documentation in sync with the actual API, as developers can generate client libraries, server stubs, and API tests directly from the API specification. This integration of design and documentation significantly enhances the development process, making it easier for teams to collaborate and understand the API functionalities, reducing misunderstandings and easing the learning curve for new developers.

While other options mention aspects related to APIs, such as performance monitoring, security testing, and usage auditing, those are not the primary functions of Swagger.