Currently, I don’t think there is a way to tell if an item is assigned to a secure zone or not.
It would be good to have the secured status of an item available in the liquid output so we can filter/sort by it (eg: use it to filter out secure items from a list if needed, or visually mark an item as secured content…)
Basic implementation would just be a boolean value:
Or perhaps better still, or as well as, output the assigned zones in an array:
"SecureZones": [ "Zone 1", "Zone 2", ... ]