Design any user-facing experience end-to-end: task flows, multi-step workflows, navigation structures, onboarding, settings, search, content creation, collaboration, signup, checkout, dashboards, notifications, error recovery, and more. Handles cross-platform adaptation (mobile/web/TV/embedded), device-aware design, accessibility, interaction specifications, and multi-channel journey mapping. Trigger when designing user flows of any kind, mapping screen sequences, optimizing task completion, specifying interactions, designing navigation, or asking "how should the user experience X?" Use this skill broadly — any time someone is working through how a user moves through a product experience, this skill applies.