描述
Choose the smallest viable React/fullstack state owner before comparing libraries. Use when the user needs to classify local UI state, shared subtree/Context state, URL or form state, server-state caches, or client workflow stores such as Zustand / Redux Toolkit / Jotai. Triggers on: global state, prop drilling, Context vs Zustand, Redux Toolkit vs Zustand, server state vs client state, React Router state management, optimistic updates, URL state, form state, and too much state in one store.