This walks you through systematic usability evaluations using Nielsen's 10 heuristics, from visibility of system status to help documentation. It structures the whole process: scope definition, multiple user perspective walkthroughs, severity ratings on a 0-4 scale, and issue documentation with specific recommendations. The approach is solid and matches how actual UX teams work, though you'll get better results with 3-5 independent evaluators comparing notes afterward. Best used when you need to catch interface problems before committing to user testing, especially for evaluating specific task flows or new feature designs. The severity framework helps prioritize what actually needs fixing versus what's just cosmetic.
npx skills add https://github.com/owl-listener/designer-skills --skill heuristic-evaluation