When you need to map out how users move through your product, this creates clean flow diagrams with proper notation for screens, decisions, branches, and error paths. It knows the difference between task flows (single linear path), user flows (multiple branches), and wire flows (with wireframe thumbnails), and pushes you to start with the happy path before layering in edge cases. The annotations cover decision criteria, system actions, and async processes, which means you're not just getting boxes and arrows but actually useful documentation. It enforces consistent labeling on every connector, so six months from now someone can actually follow what you built.
npx skills add https://github.com/owl-listener/designer-skills --skill user-flow-diagram