Descriptions

The describedAs() element is used to provide a short description of the action parameter to the user.

In the Web UI (Wicket viewer) it is displayed as a 'tool tip'.

For example:

public class Customer {

    public Order placeOrder(
          Product product,
          @ParameterLayout(
              describedAs = "The quantity of the product being ordered"
          )
          int quantity) {
        // ...
    }

    // ...
}