TypeScript Best Practices Follows type-first, functional, and error handling patterns from CLAUDE.md. This skill covers language-specific idioms only. Pair with React Best Practices When working with React components ( , files or imports), always load alongside this skill. This skill covers TypeScript fundamentals; React-specific patterns (effects, hooks, refs, component design) are in the dedicated React skill. Make Illegal States Unrepresentable Use the type system to prevent invalid states at compile time. Discriminated unions for mutually exclusive states: Branded types for domain primiti…