It is a simple data model:
In order to use Smart Controls, the OData metadata document needs to contain a few key elements such as the "sap:" annotations (see UI5 documentation) - I found the respective part in the CAP documentation and updated my CAP service accordingly:
The metadata document now looks like this:
As far as I can see, that pretty much matches the example in the UI5 documentation (except "DESCR" is "name" in my example). Also, the CAP documentation (specific part for pre-defined types like "Currencies") states that "all SAP Fiori UIs [...] will automatically receive Value Help for currencies". However, my UI5 smart control does not display any ValueHelp (the SmartLabel works!):
Does anyone have any ideas why the ValueHelp won't show up?