... usage, you only have to describe the data type requested by the command and the command itself: user interaction and screen layout are automatically adapted so you don't have to care about it, but for complex situations, CCFE is programmable with your preferred shell interpreter and can propose lists of admitted values selectable by user for parameters to enter.
CCFE don't need changes to called scripts or commands, so they can indifferently be executed with CCFE interface or CLI.