How do I install the Core Vitals Fixer skill?

Run npx skillmds@latest add modbender/core-vitals-fixer 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 Core Vitals Fixer skill do?

Fix Core Web Vitals issues with AI guidance. Use when your Lighthouse scores are bad. It is listed under Coding & Dev Tools on SkillMD.

Is Core Vitals Fixer safe to use?

This skill has not completed SkillMD's automated safety review yet. Independent scanners report: SkillSpector: PASS, Skill Scanner: PASS. Capability flags: makes network calls. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Core Vitals Fixer?

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 Core Vitals Fixer free to use?

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

Who published Core Vitals Fixer?

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

Core Vitals Fixer by modbender — Agent Skill

Name: Core Vitals Fixer
Rating: 4.2 (5 reviews)
Author: modbender

File contents

Core Web Vitals Fixer

Your LCP is 4 seconds, CLS keeps jumping, and FID feels sluggish. This tool scans your code and tells you exactly what to fix and how.

One command. Zero config. Just works.

Quick Start

npx ai-core-vitals ./src/

What It Does

Analyzes your code for Core Web Vitals issues
Identifies LCP, FID, and CLS problems
Provides specific fixes with code examples
Prioritizes issues by impact

Usage Examples

# Scan your source directory
npx ai-core-vitals ./src/

# Scan app directory
npx ai-core-vitals ./app/

# Focus on specific metric
npx ai-core-vitals ./src/ --metric lcp

Best Practices

Fix LCP first - it's usually the biggest win
Lazy load below the fold - don't load what users can't see
Reserve space for images - prevents CLS
Defer non-critical JS - improves FID

When to Use This

Lighthouse scores are tanking your SEO
Users complain about slow page loads
Core Web Vitals failing in Search Console
Building a new site and want to start optimized

Part of the LXGIC Dev Toolkit

This is one of 110+ free developer tools built by LXGIC Studios. No paywalls, no sign-ups, no API keys on free tiers. Just tools that work.

Find more:

GitHub: https://github.com/LXGIC-Studios
Twitter: https://x.com/lxgicstudios
Substack: https://lxgicstudios.substack.com
Website: https://lxgicstudios.com

Requirements

No install needed. Just run with npx. Node.js 18+ recommended. Needs OPENAI_API_KEY environment variable.

npx ai-core-vitals --help

How It Works

Scans your code files for common performance antipatterns, then sends them to GPT-4o-mini. The AI identifies issues affecting LCP, CLS, and FID and provides actionable fixes with priority rankings.

License

MIT. Free forever. Use it however you want.

Built by LXGIC Studios

GitHub: github.com/lxgicstudios/ai-core-vitals
Twitter: @lxgicstudios

---name: core-vitals-fixerdescription: Fix Core Web Vitals issues with AI guidance. Use when your Lighthouse scores are bad.--- # Core Web Vitals Fixer Your LCP is 4 seconds, CLS keeps jumping, and FID feels sluggish. This tool scans your code and tells you exactly what to fix and how. **One command. Zero config. Just works.** ## Quick Start ```bash npx ai-core-vitals ./src/ ``` ## What It Does - Analyzes your code for Core Web Vitals issues - Identifies LCP, FID, and CLS problems - Provides specific fixes with code examples - Prioritizes issues by impact ## Usage Examples ```bash # Scan your source directory npx ai-core-vitals ./src/ # Scan app directory npx ai-core-vitals ./app/ # Focus on specific metric npx ai-core-vitals ./src/ --metric lcp ``` ## Best Practices - **Fix LCP first** - it's usually the biggest win - **Lazy load below the fold** - don't load what users can't see - **Reserve space for images** - prevents CLS - **Defer non-critical JS** - improves FID ## When to Use This - Lighthouse scores are tanking your SEO - Users complain about slow page loads - Core Web Vitals failing in Search Console - Building a new site and want to start optimized ## Part of the LXGIC Dev Toolkit This is one of 110+ free developer tools built by LXGIC Studios. No paywalls, no sign-ups, no API keys on free tiers. Just tools that work. **Find more:** - GitHub: https://github.com/LXGIC-Studios - Twitter: https://x.com/lxgicstudios - Substack: https://lxgicstudios.substack.com - Website: https://lxgicstudios.com ## Requirements No install needed. Just run with npx. Node.js 18+ recommended. Needs OPENAI_API_KEY environment variable. ```bash npx ai-core-vitals --help ``` ## How It Works Scans your code files for common performance antipatterns, then sends them to GPT-4o-mini. The AI identifies issues affecting LCP, CLS, and FID and provides actionable fixes with priority rankings. ## License MIT. Free forever. Use it however you want. --- **Built by LXGIC Studios** - GitHub: [github.com/lxgicstudios/ai-core-vitals](https://github.com/lxgicstudios/ai-core-vitals) - Twitter: [@lxgicstudios](https://x.com/lxgicstudios)

Frequently asked questions

Core Vitals Fixer