We don't have an auto-add mode or something like this.
I personally would have the tendency to implement this using a DatasetModel instead of an invoke method. All you're doing is to create new records with given values. There's no need to use an invokable method for that purpose.
DEFINE VARIABLE oCustomer AS CustomerDatasetModel NO-UNDO.
oCustomer = NEW CustomerDatasetModel () .
oCustomer:TrackingChanges = TRUE.
oCustomer:Customer:Create().
oCustomer:Customer:Name = "Roger".
oCustomer:SaveChanges ().