# Reviewing State Management > Review state management patterns for React 19 best practices. Use when reviewing component state, Context usage, or state architecture. Use when this capability is needed. - Skill: `tomevault-io/reviewing-state-management` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/reviewing-state-management` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/reviewing-state-management/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Web & Frontend - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/reviewing-state-management --- # Review: State Management ## Checklist ### State Immutability - [ ] No direct state mutation - [ ] Using spread operators or immutable update patterns - [ ] Arrays updated with map/filter/concat (not push/splice) - [ ] Objects updated with spread or Object.assign ### State Location - [ ] Local state used when appropriate - [ ] Context only for cross-cutting concerns - [ ] No prop drilling through 3+ levels - [ ] Frequently changing state not in Context ### useReducer Usage - [ ] Used for complex state logic - [ ] Reducer functions are pure - [ ] Action types are consistent - [ ] State updates follow patterns ### Context Patterns - [ ] Split contexts for different concerns - [ ] Using `use()` API in React 19 (not `useContext`) - [ ] Context providers at appropriate level - [ ] No unnecessary re-renders ### Anti-Patterns - [ ] ❌ Direct state mutation (`state.push()`, `state.x = y`) - [ ] ❌ Context for frequently changing values - [ ] ❌ Excessive prop drilling - [ ] ❌ God components managing too much state For comprehensive state patterns, see: `research/react-19-comprehensive.md`. --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/djankies) — claim your Tome and manage your conversions.