What problem does it solve? Design decisions about state machines, data models, and UI layouts often look reasonable on paper but fail in practice. This Skill builds throwaway prototypes that let you press buttons, flip between variants, and discover flaws in the idea before committing to real implementation. ## Core Features & Use Cases - Logic Prototypes: Build a lightweight interactive terminal app with a pure reducer, state machine, or function set behind it, so you can drive state transitions by hand and watch edge cases break. - UI Prototypes: Generate 3-5 structurally different UI variants on one route, switchable via a ?variant= URL param and a floating bottom bar with arrow-key cycling. - Use Case: You are unsure whether a state machine handles a specific edge case. The Skill creates a runnable terminal prototype with keyboard shortcuts that mutate in-memory state and re-render the full frame after every action, so you can feel the problem immediately. ## Quick Start Ask the assistant to prototype the state machine or page design you are unsure about, and it will build a runnable throwaway prototype you can drive yourself.