What Are Claude Code Skills?

If you've been using Claude Code, you're probably using it the basic way — open a project, start chatting, ask it to write code. That works fine. But there's a layer on top of that most people miss entirely: Skills.

What Is a Skill?

A Skill is a markdown file that gives Claude specialized knowledge for a specific task. When a skill is installed in your project, Claude automatically knows when to use it based on what you're asking.

Think of it like hiring a specialist. Regular Claude is a generalist. A skill turns Claude into an expert in one specific domain — UI design, marketing copy, code reviews, whatever the skill covers.

Where Do Skills Live?

Skills go in one of two places:

# Project-specific skill (only for this project)
your-project/.claude/skills/<skill-name>/SKILL.md

# Personal skill (available across all your projects)
~/.claude/skills/<skill-name>/SKILL.md

The difference matters. A skill for your company's design system belongs in the project folder. A skill for writing better commit messages belongs in your personal folder so every project can use it.

How Does Claude Know When to Use a Skill?

This is the clever part. Every skill has a description field at the top — and that description is what Claude reads to decide whether to activate it.

---
name: ui design system
description: Use when building UI components, choosing colors, picking fonts, or reviewing design code
---

When you say "help me pick a color palette for my dashboard," Claude sees that description and knows to pull in the design skill. You don't have to manually invoke it.

A Real Example: UI UX Pro Max

UI UX Pro Max is a skill that gives Claude a full design intelligence system — 67 UI styles, 96 color palettes, 57 font pairings, and guidelines for 13 tech stacks.

Without the skill, if you ask Claude "what colors should I use for my SaaS dashboard?" you get a generic answer. With the skill installed, Claude runs a reasoning engine against industry-specific rules and returns a complete, opinionated design system tailored to your product.

That's the difference a skill makes.

How to Install a Skill

1. Download or clone the skill files
2. Copy the skill folder into .claude/skills/ in your project (or ~/.claude/skills/ for personal use)
3. That's it — Claude picks it up automatically on the next session

Skills vs CLAUDE.md

You might be wondering: can't I just put instructions in my CLAUDE.md file instead?

You can, but skills are better for complex, reusable knowledge. CLAUDE.md is for project-specific rules and context — your tech stack, your build commands, gotchas Claude can't figure out from the code. Skills are for deep domain expertise you want to apply repeatedly, potentially across multiple projects.

Use both. They work together.

What Skills Are Available?

The ecosystem is still early, but growing fast. A few worth knowing about:

• UI UX Pro Max — design system generation for any stack
• Marketing Skills — 33 skills covering SEO, copywriting, email, ads, and CRO
• Community-built skills on GitHub for code review, testing patterns, Docker deployment, and more

You can also write your own. If you find yourself giving Claude the same context over and over, that's a sign you should turn it into a skill.

The Bottom Line

Skills are the fastest way to level up what Claude Code can do without writing a single line of code. If you're a beginner using Claude to build apps, installing one or two domain-specific skills is probably the highest-leverage thing you can do today.