This is throwaway code with a purpose: answer a design question fast, then delete it. It routes you to one of two branches depending on what you're testing. If you need to validate state logic or a data model, it builds a tiny interactive terminal app. If you're exploring UI options, it generates radically different variations on one route with a toggle bar. The smart bit is that it enforces the throwaway nature from the start: no tests, no persistence, located next to real code but clearly marked as temporary. When you're done, you capture the answer and delete the prototype. Works well when you'd otherwise bikeshed in Figma or argue about state machines in a PR.
npx skills add https://github.com/mattpocock/skills --skill prototype