When developing use cases for your portal, keep the following elements in mind:
Priority. Describes the priority, or ranking of the use case. For example, this could range from high to medium to low.
Context of use. Describes the setting or environment in which the use case occurs.
Scope. Describes the conditions and limititations of the use case.
Primary user. Describes what kind of user this applies to, for example, an end user or an administrator.
Special requirements. Describes any other conditions that apply.
Stakeholders. Describes the people who have a vested interest in how a product decision is made or carried out.
Precondition. Describes the prerequisites that must be met for the use case to occur.
Minimal guarantees. Describes the minimum that must occur if the use case is not successfully completed.
Success guarantees. Describes what happens if the use case is successfully completed.
Trigger. Describes the particular item in the system that causes the event to occur.
Description. Provides a step-by-step account of the use case, from start to finish.