AI + UX Code Review Checklist: 17 Critical Frontend Issues to Catch Before Production

Frontend code reviews often focus on functionality, but poor UX and accessibility can be just as damaging to user experience. With AI-powered code review tools, teams can now systematically catch UX anti-patterns, accessibility violations, and performance bottlenecks before they reach production. This checklist provides 17 critical frontend issues that every engineering team should check during code review.

Accessibility Issues to Catch in Code Review

1. Missing Alt Text for Images

Images without alt attributes create barriers for screen reader users. AI code review tools can automatically flag missing alt text and suggest improvements based on context.

2. Inadequate Color Contrast Ratios

WCAG guidelines require minimum contrast ratios of 4.5:1 for normal text and 3:1 for large text. AI tools can analyze CSS and detect contrast violations automatically.

3. Missing ARIA Labels and Roles

Interactive elements need proper ARIA attributes for screen readers. Look for buttons, form controls, and custom widgets missing accessibility metadata.

4. Poor Keyboard Navigation

All interactive elements must be accessible via keyboard. Review JavaScript event handlers to ensure they support both mouse and keyboard interactions.

5. Missing Focus Indicators

Users navigating with keyboards need visible focus indicators. Avoid CSS that removes default focus styles without providing alternatives.

6. Improper Heading Hierarchy

Headings should follow logical order (h1→h2→h3) without skipping levels. Screen readers use heading structure for navigation.

Performance Issues That Impact UX

7. Unused CSS and JavaScript

Dead code increases bundle sizes and slows loading. AI code review can identify unused imports, functions, and CSS rules across your entire codebase.

8. Large Uncompressed Images

Images over 100KB without optimization severely impact mobile users. Check for missing compression, wrong formats, and oversized dimensions.

9. Missing Lazy Loading

Images below the fold should use lazy loading to improve initial page load times. Modern browsers support native lazy loading with the loading="lazy" attribute.

10. Blocking Render Resources

JavaScript and CSS files that block the critical rendering path delay first contentful paint. Review resource loading patterns and async/defer attributes.

11. Memory Leaks in Single Page Applications

Event listeners, subscriptions, and timers that aren't cleaned up cause memory leaks. Check component unmount logic and useEffect cleanup functions.

UX Anti-Patterns to Avoid

12. Poor Error Messaging

Generic error messages like "Something went wrong" frustrate users. Review error handling to ensure messages are specific and actionable.

13. Missing Loading States

Users need feedback during async operations. Check for loading indicators, skeleton screens, or progress bars in all async workflows.

14. Inconsistent Design Patterns

Buttons, inputs, and interactions should follow consistent patterns. AI tools can flag deviations from your design system components.

15. Non-Responsive Layouts

Layouts should work across all screen sizes. Review CSS media queries, flexible grids, and viewport meta tags for mobile compatibility.

16. Form Validation Issues

Forms should validate on blur, show clear error messages, and prevent invalid submissions. Check both client-side and server-side validation logic.

17. Poor Mobile Interaction Patterns

Touch targets should be at least 44px, hover states don't exist on mobile, and scrolling should feel natural. Review touch event handling and mobile-specific CSS.

Implementing AI-Powered UX Code Reviews

Modern AI code review tools can automatically detect many of these issues during the review process. Tools like Propel can:

• Scan for WCAG compliance violations
• Analyze bundle sizes and suggest optimizations
• Flag inconsistent design system usage
• Detect performance anti-patterns
• Suggest accessibility improvements

Setting Up Your UX Code Review Process

To effectively catch these issues, integrate UX checks into your standard code review workflow:

1. Configure your AI code review tool to check for accessibility and performance issues
2. Create custom rules for your design system components
3. Set up automated lighthouse scoring in your CI/CD pipeline
4. Train your team to recognize common UX anti-patterns
5. Establish UX review criteria alongside functional requirements

By systematically checking for these 17 critical frontend issues during code review, your team can ship more accessible, performant, and user-friendly applications. AI-powered code review tools make this process scalable and consistent across your entire engineering organization.