react-useeffect
React useEffect best practices from official docs. Use when writing/reviewing useEffect, useState for derived values, data fetching, or state synchronization. Teaches when NOT to use Effect and better alternatives.
Best use case
react-useeffect is best used when you need a repeatable AI agent workflow instead of a one-off prompt. It is especially useful for teams working in multi. React useEffect best practices from official docs. Use when writing/reviewing useEffect, useState for derived values, data fetching, or state synchronization. Teaches when NOT to use Effect and better alternatives.
React useEffect best practices from official docs. Use when writing/reviewing useEffect, useState for derived values, data fetching, or state synchronization. Teaches when NOT to use Effect and better alternatives.
Users should expect a more consistent workflow output, faster repeated execution, and less time spent rewriting prompts from scratch.
Practical example
Example input
Use the "react-useeffect" skill to help with this workflow task. Context: React useEffect best practices from official docs. Use when writing/reviewing useEffect, useState for derived values, data fetching, or state synchronization. Teaches when NOT to use Effect and better alternatives.
Example output
A structured workflow result with clearer steps, more consistent formatting, and an output that is easier to reuse in the next run.
When to use this skill
- Use this skill when you want a reusable workflow rather than writing the same prompt again and again.
When not to use this skill
- Do not use this when you only need a one-off answer and do not need a reusable workflow.
- Do not use it if you cannot install or maintain the related files, repository context, or supporting tools.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/react-useeffect/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How react-useeffect Compares
| Feature / Agent | react-useeffect | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
React useEffect best practices from official docs. Use when writing/reviewing useEffect, useState for derived values, data fetching, or state synchronization. Teaches when NOT to use Effect and better alternatives.
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
Related Guides
SKILL.md Source
# You Might Not Need an Effect
Effects are an **escape hatch** from React. They let you synchronize with external systems. If there is no external system involved, you shouldn't need an Effect.
## Quick Reference
| Situation | DON'T | DO |
|-----------|-------|-----|
| Derived state from props/state | `useState` + `useEffect` | Calculate during render |
| Expensive calculations | `useEffect` to cache | `useMemo` |
| Reset state on prop change | `useEffect` with `setState` | `key` prop |
| User event responses | `useEffect` watching state | Event handler directly |
| Notify parent of changes | `useEffect` calling `onChange` | Call in event handler |
| Fetch data | `useEffect` without cleanup | `useEffect` with cleanup OR framework |
## When You DO Need Effects
- Synchronizing with **external systems** (non-React widgets, browser APIs)
- **Subscriptions** to external stores (use `useSyncExternalStore` when possible)
- **Analytics/logging** that runs because component displayed
- **Data fetching** with proper cleanup (or use framework's built-in mechanism)
## When You DON'T Need Effects
1. **Transforming data for rendering** - Calculate at top level, re-runs automatically
2. **Handling user events** - Use event handlers, you know exactly what happened
3. **Deriving state** - Just compute it: `const fullName = firstName + ' ' + lastName`
4. **Chaining state updates** - Calculate all next state in the event handler
## Decision Tree
```
Need to respond to something?
├── User interaction (click, submit, drag)?
│ └── Use EVENT HANDLER
├── Component appeared on screen?
│ └── Use EFFECT (external sync, analytics)
├── Props/state changed and need derived value?
│ └── CALCULATE DURING RENDER
│ └── Expensive? Use useMemo
└── Need to reset state when prop changes?
└── Use KEY PROP on component
```
## Detailed Guidance
- [Anti-Patterns](./anti-patterns.md) - Common mistakes with fixes
- [Better Alternatives](./alternatives.md) - useMemo, key prop, lifting state, useSyncExternalStoreRelated Skills
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