use-legend

MUST be used when building React components with @usels/core, @usels/web, @usels/integrations, "use scope" directive, or observable-bearing props. Covers scope rules, reactive reads, component props, rendering boundaries, library hook interop, third-party integration, and mixing with normal React hooks.

Use when building a custom reactive utility for an app using @usels/core — decides between "use scope" core-only style vs traditional 2-layer hook+core style and shows the pattern for each

Use when looking up what @usels/core or @usels/web hooks exist, their signatures, options, or return types — covers 100+ Observable-native React hooks built on Legend-State

Use when writing tests for custom hooks or "use scope" components — covers rerender stability, element lifecycle (null→element→null), and reactive options change scenarios