A trigger is the action an actor takes to start a use case. Describe it from the actor’s point of view, then follow it with the use case’s action steps. section 3.6.2
Search Catalogue
The customer presses the Search button after entering target book attributes in an online form. That action triggers the catalogue search use case, which returns matching books. section 3.6.2
Specify a trigger alongside the surrounding use-case details:
- Identify the actor’s action that starts the use case. section 3.6.2
- Record preconditions, primary and alternate action sequences, and postconditions around that starting event. section 3.6.2
