React Code Review

This command invokes the react-reviewer agent for React-specific code review. For pull requests touching .tsx/.jsx files, both react-reviewer and typescript-reviewer should run — each owns a distinct lane.

What This Command Does

1. Identify React Changes: Find modified .tsx/.jsx files (and React-containing .ts/.js files) via git diff
2. Run Lint: Execute eslint with eslint-plugin-react-hooks and eslint-plugin-jsx-a11y
3. Typecheck: Run tsc --noEmit or the project's canonical typecheck command
4. Review React Lanes Only: Hook rules, RSC boundaries, accessibility, render performance, React-specific security
5. Generate Report: Categorize issues by severity (CRITICAL / HIGH / MEDIUM)

When to Use

Use /react-review when:

• A PR or commit touches .tsx/.jsx files
• After writing or modifying React components, custom hooks, or pages
• Before merging React code
• Auditing accessibility on UI components
• Reviewing a new hook for rules-of-hooks and dependency correctness
• Auditing a Next.js App Router server/client component boundary

For pure .ts/.js changes with no React imports, use /code-review (general) or invoke typescript-reviewer directly.

Scope vs /code-review and TypeScript Review

On a TSX/JSX PR, invoke both react-reviewer and typescript-reviewer. Findings from each are non-overlapping by design.

Review Categories

CRITICAL (Must Fix)

• dangerouslySetInnerHTML with unsanitized input
• href/src with unvalidated user URLs (javascript:, data:)
• Server Action without input validation
• Secret in client bundle (NEXT_PUBLIC_*, VITE_*, REACT_APP_*)
• localStorage/sessionStorage for session tokens
• Conditional hook calls (violates Rules of Hooks)
• Direct state mutation
• Hook called outside a component or custom hook

HIGH (Should Fix)

• Missing useEffect/useMemo/useCallback deps (disabled exhaustive-deps without justification)
• Effect for derived state
• Effect missing cleanup
• Stale closures in handlers/intervals
• Server-only imports in Client Components
• Sensitive data leaked via props to Client Components
• Server Actions without auth checks
• Accessibility violations (missing labels, non-semantic interactive elements, ARIA misuse)
• key={index} in dynamic lists
• Duplicated state, useEffect chains

MEDIUM (Consider)

• Over-memoization without measured win
• Inline new object/function as prop to memoized child
• Suspense at route root only (no progressive reveal)
• Long lists without virtualization
• High-frequency value via useContext
• Roll-your-own validation in non-trivial forms
• Prop drilling beyond 3 levels
• Component over 200 lines
• Class components in new code

Automated Checks Run

# Lint (required for any meaningful review)
npx eslint . --ext .tsx,.jsx,.ts,.js

# Typecheck (skip cleanly for JS-only projects)
npm run typecheck --if-present
[ -f tsconfig.json ] && tsc --noEmit -p tsconfig.json

# Targeted a11y rules
npx eslint . --rule 'jsx-a11y/alt-text: error' \
              --rule 'jsx-a11y/anchor-is-valid: error' \
              --rule 'jsx-a11y/click-events-have-key-events: error'

# Supply-chain
npm audit

If eslint-plugin-react-hooks or eslint-plugin-jsx-a11y is not configured, the review will flag the gap as a HIGH config issue and continue.

Example Usage

User: /react-review

Agent:
# React Code Review Report

## Files Reviewed
- src/components/UserCard.tsx (modified)
- src/hooks/useUser.ts (new)

## Lint Results
PASS: eslint clean
PASS: typecheck clean

## Issues Found

[CRITICAL] Unsanitized dangerouslySetInnerHTML
File: src/components/UserCard.tsx:42
Issue: User-controlled bio rendered as raw HTML.
Why: XSS via stored script tags in user input.
Fix: Sanitize with DOMPurify or render as text:
```tsx
import DOMPurify from "isomorphic-dompurify";
<div dangerouslySetInnerHTML={{ __html: DOMPurify.sanitize(user.bio) }} />
```

[HIGH] Effect cleanup missing
File: src/hooks/useUser.ts:18
Issue: `fetch` call without AbortController; setState on unmounted component possible.
Fix: Add AbortController and cleanup:
```ts
useEffect(() => {
  const ac = new AbortController();
  fetch(`/api/users/${id}`, { signal: ac.signal })
    .then(r => r.json())
    .then(setUser);
  return () => ac.abort();
}, [id]);
```

## Summary
- CRITICAL: 1
- HIGH: 1
- MEDIUM: 0

Recommendation: FAIL: Block merge until CRITICAL issue is fixed

Approval Criteria

Integration with Other Commands

• Run /react-build first if the build is broken
• Run /react-test to ensure component tests pass
• Run /react-review before merging
• Use /code-review for non-React-specific concerns on the same PR

Related

• Agent: agents/react-reviewer.md
• Companion agent: agents/typescript-reviewer.md (run alongside for TSX/JSX PRs)
• Skills: skills/react-patterns/, skills/react-testing/, skills/accessibility/
• Rules: rules/react/