Standard tools, such as Postman, can be used to navigate the Business Central API in order to discover what is available and to test requests.

After you configure your sandbox for basic authentication, you just need to enter a valid API URL and your basic authentication information, and then submit the request. 

From there, you can view the results of the request in readable JSON format.

You can use Postman to perform any testing of the API prior to ensure your request is formatted properly, and to ensure the data that is returned is what you expect.