How would you answer an interview scenario involving use case boundaries?

For an interview scenario involving use case boundaries, I would first clarify the business goal, scale, constraints, and the failure or quality attribute the interviewer wants to explore. Use-case boundaries define the operations the application supports and the contracts needed to execute them. For production, name use cases around user or business goals, keep inputs and outputs explicit, and define transactional scope intentionally. I would then explain the main alternatives and tradeoffs, identify likely failure modes, and describe how I would validate the solution through testing, observability, security controls, and recovery or rollback planning.