Claude Code skills are custom commands that extend Claude's capabilities in your development workflow. Think of them as reusable prompts that you can invoke with a simple slash command.
In this guide, we'll walk through everything you need to know to create your first skill and level up your Claude Code experience.
What Are Claude Code Skills?
Skills are markdown files that define custom behaviors for Claude Code. When you type /skill-name, Claude loads the skill's instructions and executes them in your current context.
Why use skills?
- Consistency: Same behavior every time you invoke it
- Speed: One command instead of typing long prompts
- Shareability: Share skills with your team
- Context: Skills can access your codebase automatically
Creating Your First Skill
Skills live in your project's .claude/skills/ directory. Let's create a simple code review skill.
Step 1: Create the Directory
mkdir -p .claude/skills
Step 2: Create the Skill File
Create .claude/skills/review.md:
# Code Review
Review the selected code for:
1. **Bugs**: Logic errors, edge cases, null checks
2. **Performance**: Inefficient algorithms, unnecessary loops
3. **Security**: Input validation, injection risks
4. **Readability**: Naming, comments, structure
Provide specific suggestions with code examples.
Step 3: Use Your Skill
Now you can type /review in Claude Code, and it will review your code using these criteria.
Skill Best Practices
Keep Skills Focused
Each skill should do one thing well. Instead of a massive "do everything" skill, create specific ones:
/review- Code review/test- Generate tests/docs- Write documentation/refactor- Suggest improvements
Use Clear Instructions
Be specific about what you want. Compare these:
Vague:
Review this code
Specific:
Review this code for security vulnerabilities. Focus on:
- SQL injection
- XSS attacks
- Authentication bypasses
Format findings as: [SEVERITY] Description + Fix
Include Examples
Show Claude what good output looks like:
## Example Output
**Finding**: Missing input validation on user ID
**Severity**: High
**Location**: line 45
**Fix**: Add `parseInt()` and range check
Advanced Skill Patterns
Dynamic Context
Skills can reference your current file or selection:
Analyze the current file and suggest improvements based on:
- The project's existing patterns
- Dependencies in package.json
- Related test files
Multi-Step Skills
For complex tasks, break them into steps:
## Task: Add New API Endpoint
1. First, analyze existing endpoints in `/api` for patterns
2. Create the new endpoint following those patterns
3. Add input validation
4. Generate tests
5. Update the API documentation
Conditional Logic
Guide Claude based on context:
If this is a React component:
- Check for proper hook usage
- Verify prop types
- Look for re-render issues
If this is an API route:
- Check authentication
- Validate request body
- Ensure proper error handling
Sharing Skills with Your Team
Skills can be committed to your repository, making them available to everyone:
your-project/
├── .claude/
│ └── skills/
│ ├── review.md
│ ├── test.md
│ └── deploy-checklist.md
├── src/
└── package.json
This ensures consistent AI assistance across your entire team.
What's Next?
Now that you understand the basics, try creating skills for your most common tasks:
- Start simple: Pick one repetitive task you do daily
- Write the skill: Be specific about what you want
- Test and iterate: Refine based on results
- Share: Add to your repo for the team
Want to automate entire workflows, not just individual commands? nNode lets you chain AI agents together to handle complex, multi-step processes automatically.