Improve design mockups from critique (design-review, user studies, a multi-perspective council, a UI lint pass, or raw notes): triage keep/change/kill, produce a new version with a per-change rationale trail so the next test can measure improvement. If no critique exists yet, runs the full test-iterate-test loop (review + studies + lint) around the mockup. Reaches for a design system if one exists. Use when: run design-iteration on this mockup, iterate on these designs, revise the mockups from feedback, incorporate the review, next design iteration, close the loop on design feedback.