| name | usability-test |
| description | Plan and run a usability test around realistic user tasks, representative participants, observable success, moderator discipline, evidence capture, and prioritized product implications. |
Usability Test
Use when a product flow, prototype, or implementation needs evidence about whether intended users can understand and complete important tasks.
Procedure
- Define the product decisions, target participants, critical tasks, prototype or build revision, and what successful task completion means.
- Create realistic scenarios that give participants a goal without telling them which control or path to use.
- Prepare starting state, test data, environment, recording or note method, consent, and any moderator handoff rules.
- Ask participants to work naturally and avoid rescuing them until the point of intervention is itself recorded as evidence.
- Observe task success, route, hesitation, errors, recovery, terminology confusion, missed information, repeated attempts, and requests for help.
- Use follow-up questions after behavior occurs to understand intent and interpretation without leading the action beforehand.
- Distinguish interface defects from prototype limitations, participant-specific unfamiliarity, and technical failures unrelated to the design.
- Synthesize patterns and severe outliers by task impact and confidence, then hand product implications to the appropriate design or product owner.
Decision rules
- A test task should describe the user's goal, not the UI steps.
- Moderator assistance changes the evidence and must be recorded.
- Five participants is not a universal rule; sample needs depend on variation, method, and claim.
- Usability testing finds interaction evidence, not population-level preference percentages from a small qualitative sample.
Quality gate
The test is complete when participant and build context are recorded, realistic tasks produce observable behavior, moderator influence is visible, findings distinguish design from test-environment artifacts, and prioritized implications trace back to specific evidence.