I think you are trying to something with ISG (try to have some custom integration interfaces) and you trying to generate ildt file for a custom package, but you are failing because you don't follow the standards. you don't have the required things in place.. Pls should be there, and it should contain a correct annonation.
See -> Oracle® E-Business Suite Integrated SOA Gateway Developer's Guide..
The Integration Repository Annotation Standards are defined in that document.
Also see -> Oracle® E-Business Suite Integrated SOA Gateway Implementation Guide
https://docs.oracle.com/cd/E26401_01/doc.122/e20925/T511175T543269.htm