WSO2 API Manager has an integrated Swagger UI, which is part of the Swagger project.
Swagger is a 100% open source, standard, language-agnostic specification and a complete framework for describing, producing, consuming, and visualizing RESTful APIs, without the need of a proxy or third-party services. Swagger allows consumers to understand the capabilities of a remote service without accessing its source code and interact with the service with a minimal amount of implementation logic. Swagger helps describe a services in the same way that interfaces describe lower-level programming code.
The Swagger UI is a dependency-free collection of HTML, JavaScript, and CSS that dynamically generate documentation from a Swagger-compliant API. Swagger-compliant APIs give you interactive documentation, client SDK generation and more discoverability. The Swagger UI has JSON code and its UI facilitates easier code indentation, keyword highlighting and shows syntax errors on the fly. You can add resource parameters, summaries and descriptions to your APIs using the Swagger UI.
Also, see the Swagger 2.0 specification.
In this tutorial, let's see how you can add interactive documentation to an API by directly editing the Swagger code and through the API Publisher UI.
This tutorial uses the PhoneVerification API created in Create and Publish an API.