These adapters need information on the API to be called. You can provide this information in two ways:
Via a connector This is the easiest way to provide the necessary information. The Designer allows for importing different connector configurations (see Creating Connectors for more information about that).
Via a manual data model If you do not have a configuration file to import at hand, you can create the necessary resources and interface definitions manually to the Implementation folder. Refer to the related adapter pages for more information on how to do that.
The image below shows the interaction between connector and adapter using a REST service example.