Frontend Code Review

# Frontend Code Review

## Intent
Use this skill whenever the user asks to review frontend code (especially `.tsx`, `.ts`, or `.js` files). Support two review modes:

1. **Pending-change review** – inspect staged/working-tree files slated for commit and flag checklist violations before submission.
2. **File-targeted review** – review the specific file(s) the user names and report the relevant checklist findings.

Stick to the checklist below for every applicable file and mode.

## Checklist
See [references/code-quality.md](references/code-quality.md), [references/performance.md](references/performance.md), [references/business-logic.md](references/business-logic.md) for the living checklist split by category—treat it as the canonical set of rules to follow.

Flag each rule violation with urgency metadata so future reviewers can prioritize fixes.

## Review Process
1. Open the relevant component/module. Gather lines that relate to class names, React Flow hooks, prop memoization, and styling.
2. For each rule in the review point, note where the code deviates and capture a representative snippet.
3. Compose the review section per the template below. Group violations first by **Urgent** flag, then by category order (Code Quality, Performance, Business Logic).

## Required output
When invoked, the response must exactly follow one of the two templates:

### Template A (any findings)
```
# Code review
Found <N> urgent issues need to be fixed:

## 1 <brief description of bug>
FilePath: <path> line <line>
<relevant code snippet or pointer>


### Suggested fix
<brief description of suggested fix>

---
... (repeat for each urgent issue) ...

Found <M> suggestions for improvement:

## 1 <brief description of suggestion>
FilePath: <path> line <line>
<relevant code snippet or pointer>


### Suggested fix
<brief description of suggested fix>

---

... (repeat for each suggestion) ...
```

If there are no urgent issues, omit that section. If there are no suggestions, omit that section.

If the issue number is more than 10, summarize as "10+ urgent issues" or "10+ suggestions" and just output the first 10 issues.

Don't compress the blank lines between sections; keep them as-is for readability.

If you use Template A (i.e., there are issues to fix) and at least one issue requires code changes, append a brief follow-up question after the structured output asking whether the user wants you to apply the suggested fix(es). For example: "Would you like me to use the Suggested fix section to address these issues?"

### Template B (no issues)
```
## Code review
No issues found.
```



# Rule Catalog — Code Quality

## Conditional class names use utility function

IsUrgent: True
Category: Code Quality

### Description

Ensure conditional CSS is handled via the shared `classNames` instead of custom ternaries, string concatenation, or template strings. Centralizing class logic keeps components consistent and easier to maintain.

### Suggested Fix

```ts
import { cn } from '@/utils/classnames'
const classNames = cn(isActive ? 'text-primary-600' : 'text-gray-500')
```

## Tailwind-first styling

IsUrgent: True
Category: Code Quality

### Description

Favor Tailwind CSS utility classes instead of adding new `.module.css` files unless a Tailwind combination cannot achieve the required styling. Keeping styles in Tailwind improves consistency and reduces maintenance overhead.

Update this file when adding, editing, or removing Code Quality rules so the catalog remains accurate.

## Classname ordering for easy overrides

### Description

When writing components, always place the incoming `className` prop after the component’s own class values so that downstream consumers can override or extend the styling. This keeps your compon