Testing
These are a list of Utilities, Apps, and Tools that will help you develop in a much more productive way.
Free Webhooks
This tool will give you the ability to create free webhooks for testing. You will be given an endpoint that you can place as your webhook in other tools so that you can inspect the payload and other information.
Postman
By far the best tool you can be using when developing APIs. This will allow you to set up environments variables and sets of collections to better manage, develop, and test all your apis.