Vercel Releases Open-Source React Performance Skill for AI Coding Assistants
Vercel has released React Best Practices, a new skill designed for AI coding agents that encodes over ten years of React performance optimization knowledge into a structured, queryable framework. The tool enables developers using Cursor, Claude Code, and compatible AI assistants to systematically identify and fix performance issues in React codebases.
The Performance Problem in React Development
React developers frequently encounter performance issues that only become apparent once applications slow down:
- Async waterfalls — sequential operations blocking unnecessarily
- Bundle bloat — shipping excessive JavaScript to users
- Unnecessary re-renders — components updating when they shouldn't
- Consolidating eight separate message scans into one pass
- Parallelizing sequential database calls to cut wait time in half
- Moving JSON parsing into `useState` callbacks to eliminate repeated work
- Unnecessary re-renders
- Missing memoization
- Inefficient data fetching patterns
- Bundle size issues
The skill addresses these problems by providing AI agents with a structured framework for identifying and fixing performance issues, organized by impact level from critical to low.
Structured Optimization Framework
The skill follows a specific order of operations across eight categories:
1. Eliminate waterfalls — parallelize sequential async operations
2. Reduce bundle size — often the biggest performance gains
3. Server-side performance — optimize backend rendering
4. Client-side data fetching — improve data loading patterns
5. Re-render optimization — minimize unnecessary updates
6. Rendering performance — optimize component rendering
7. Advanced patterns — sophisticated optimization techniques
8. JavaScript performance — core language optimizations
The skill contains over 40 rules across these categories, each with an impact rating for prioritization and code examples showing problematic patterns alongside correct solutions.
Real-World Optimization Examples
The framework has demonstrated measurable improvements:
These optimizations represent knowledge that experienced React developers possess but can miss when focused on feature development.
Installation and Integration
Installation requires a single command:
```bash
npx add skill vercel-labs/agentkills
```
The skill works with Cursor, Claude Code, and other AI coding tools supporting skills. Once installed, it compiles into an `agents.md` document that AI agents reference when making optimization decisions.
For Claude Code users, the skill appears in the skills folder and can be invoked directly. Verdant users can configure it as a slash command for parallel agent workflows.
Usage in Practice
Developers can prompt AI agents to analyze slow components using the React best practices skill. The AI then checks for:
The agent suggests specific fixes based on skill rules, such as correcting missing `useEffect` dependencies or optimizing library imports.
Open Source Availability
The skill is open source under the Apache 2.0 license, available in the Vercel Labs GitHub repository. This accessibility makes it valuable for both beginners learning best practices and experienced developers catching issues they might otherwise miss.
Implications for AI-Assisted Development
The release represents a shift toward specialized, domain-specific knowledge embedded directly into AI coding tools. Rather than generic code completion, agents equipped with such skills can provide expert-level optimization guidance grounded in extensive real-world experience.