Use whenever a screenshot is captured or supplied — a bug report, a Playwright capture, a design review, a "does this look right". Read the WHOLE image, not just the thing it was sent for: sweep it against the defect checklist below, file the findings, and add them to the todo list. When a defect is later reported that this sweep should have caught, append the miss to the Misses log (in the consuming repo's .claude/screenshot-sweep/ when installed as a plugin) and add the check that would have caught it, so the checklist grows tighter over time.
