Puppeteer is a Node.js library which provides a high-level API to control Chrome/Chromium over the DevTools Protocol.

API Testing Platform that automatically generates unit test cases with dependency mocks from API calls

RapidAPI for Mac is a full-featured HTTP client that lets you test and describe the APIs you build or consume. It has a beautiful native macOS interface to compose requests, inspect server responses, generate client code and export API definitions.

Simulate APIs, integrations, and environments at enterprise scale.

Requestly is an open-source tool that simplifies API development, testing, mocking, and integration for developers and QAs.

Swagger UI allows anyone — be it your development team or your end consumers — to visualize and interact with the API’s resources without having any of the implementation logic in place