react-expert

# React Expert Research Skill

## Overview

This skill produces exhaustive documentation research on any React API or concept by searching authoritative sources (tests, source code, PRs, issues) rather than relying on LLM training knowledge.

<CRITICAL>
**Skepticism Mandate:** You must be skeptical of your own knowledge. Claude is often trained on outdated or incorrect React patterns. Treat source material as the sole authority. If findings contradict your prior understanding, explicitly flag this discrepancy.

**Red Flags - STOP if you catch yourself thinking:**
- "I know this API does X" → Find source evidence first
- "Common pattern is Y" → Verify in test files
- Generating example code → Must have source file reference
</CRITICAL>

## Invocation

```
/react-expert useTransition
/react-expert suspense boundaries
/react-expert startTransition
```

## Sources (Priority Order)

1. **React Repo Tests** - Most authoritative for actual behavior
2. **React Source Code** - Warnings, errors, implementation details
3. **Git History** - Commit messages with context
4. **GitHub PRs & Comments** - Design rationale (via `gh` CLI)
5. **GitHub Issues** - Confusion/questions (facebook/react + reactjs/react.dev)
6. **React Working Group** - Design discussions for newer APIs
7. **Flow Types** - Source of truth for type signatures
8. **TypeScript Types** - Note discrepancies with Flow
9. **Current react.dev docs** - Baseline (not trusted as complete)

**No web search** - No Stack Overflow, blog posts, or web searches. GitHub API via `gh` CLI is allowed.

## Workflow

### Step 1: Setup React Repo

First, ensure the React repo is available locally:

```bash
# Check if React repo exists, clone or update
if [ -d ".claude/react" ]; then
  cd .claude/react && git pull origin main
else
  git clone --depth=100 https://github.com/facebook/react.git .claude/react
fi
```

Get the current commit hash for the research document:
```bash
cd .claude/react && git rev-parse --short HEAD
```

### Step