| Quality scenario part | Use case part | Comments |
| Environment (context) | An exception point in the extended use case | |
| Stimulus Source | Internal (the system itself) or external (a primary actor) | |
| Stimulus | The event that satisfies the condition in the exception point | |
| Response | The MSS of the extending use case and any sub-scenarios branching from it | |
| Response measurement | Post-conditions | If the extending use case returns to the extended use case upon completion, then the results are implied by the post-conditions of the extending use case. Other wise – by the post-conditions of the extending use case |