The REST API Browser
The REST API browser is a browser that provides a visual overview of the structure and capabilities of the REST web services Record API. The data presented in the REST API browser is based on OpenAPI 3.0 metadata.
The REST API browser provides information about the available operations, field names, field types, the structure of potential HTTP responses, and a summary of all records, sublists, schema definitions and other objects.
For more information, see The REST API Browser.