Common VNF behaviors may be illustrated by use cases. For example, the ONAP R1 scope is defined by End to End Use cases showing the behavior of various ONAP platform components.  These use cases rely on some common behavior from VNFs for VNF operations including VNF Onboarding, VNF Instantiation, VNF Configuration etc. 

Additionally user stories may be helpful for expanding some VNF Requirements towards test descriptions. 

These user stories should be focused on the VNF not on ONAP platform components. 

A common template should be used to structure these user stories for completeness.

the stories should be documented in the / user stories repo