Since the WordPress 4.7 “Vaughan” release, each WordPress installation includes REST API endpoints to access and manipulate its content. These endpoints will be the foundation for the next generation of WordPress websites and applications.Today we’re releasing a brand new Open Source WordPress API console. You can use it to try these endpoints and explore the results. The console works for any website on WordPress.com and also for any self-hosted WordPress installation.
more on: https://developer.wordpress.com/2017/02/14/new-wordpress-unified-api-console/