How do I install the Performance skill?

Run npx skillmds@latest add sylphxai/performance in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

What does the Performance skill do?

Performance - Core Web Vitals, bundle size. Use when optimizing speed. It is listed under Coding & Dev Tools on SkillMD.

Is Performance safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Performance?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Performance free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Performance?

SylphxAI (@sylphxai) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Performance by sylphxai — Agent Skill

Name: Performance
Author: SylphxAI

File contents

Performance Guideline

Tech Stack

Framework: Next.js (SSR/ISR/Static)
Platform: Vercel
Tooling: Bun

Non-Negotiables

Core Web Vitals must meet thresholds (LCP < 2.5s, CLS < 0.1, INP < 200ms)
Performance regressions must be detectable

Context

Performance is a feature. Slow products feel broken, even when they're correct. Users don't read loading spinners — they leave. Every 100ms of latency costs engagement.

Don't just measure — understand. Where does time go? What's blocking the critical path? What would make the product feel instant? Sometimes small architectural changes have bigger impact than optimization.

Driving Questions

What makes the product feel slow to users?
Where are the biggest bottlenecks in the critical user journeys?
What's in the critical rendering path that shouldn't be?
How large is the JavaScript bundle, and what's bloating it?
What database queries are slow, and why?
If we could make one thing 10x faster, what would have the most impact?

Frequently asked questions

Performance