To view details about various endpoints and methods:
Hover your cursor over the Menu button located in the upper-right corner of the side navigation menu. In the menu that appears, click API Documentation. The API Documentation panel opens on the right side of the screen.

On the API Documentation panel, available API resources are organized by header. Click the Inventory header to display the methods of the Inventory resource.
Click the POST /inventories/http_requests/{inventory_name}/devices method to display detailed information about the method, including:

To test the method:
Click the Try it out button located to the right of the Parameters header. The request body becomes editable and an Execute button appears.
Modify the request body as desired. For more information, see Inventory integration variables.