Skill Creator

Skill Creator

Create well-structured Agent Skills that work across Claude Code, GitHub Copilot, VS Code, and OpenAI Codex.

What is a Skill?

A skill is a directory containing:

• SKILL.md - Instructions with YAML frontmatter
• assets/ - Templates, data files (optional)
• references/ - Additional documentation (optional)
• scripts/ - Executable code (optional)

Skills extend AI agent capabilities with domain-specific knowledge and workflows.

Creation Workflow

Step 1: Gather Requirements

Ask the user:

1. What should the skill do? (capability)
2. When should it be used? (trigger conditions)
3. What resources does it need? (templates, scripts, references)
4. Where should it be installed? (project or personal)

Step 2: Choose Skill Location

# Project skill (shared with team via git)
.claude/skills/{skill-name}/SKILL.md

# Personal skill (only for you)
~/.claude/skills/{skill-name}/SKILL.md

# agent-kit content (for distribution)
content/skills/{skill-name}/SKILL.md

Step 3: Create Directory Structure

mkdir -p {location}/{skill-name}/{assets,references,scripts}

Step 4: Write SKILL.md

Use the template from assets/skill-template.md.

Key sections:

1. Frontmatter - name, description, metadata
2. Purpose - What the skill does
3. When to Use - Trigger conditions
4. Instructions - Step-by-step guidance
5. Examples - Concrete usage examples
6. Related Skills - Links to other skills

Step 5: Add Resources (if needed)

• assets/: Templates the skill uses
• references/: Additional docs for complex topics
• scripts/: Automation scripts

Step 6: Create Slash Command

Every skill should have a corresponding slash command for easy invocation.

Command location:

# Project command (matches skill location)
.claude/commands/{skill-name}.md

# agent-kit content (for distribution) - MUST use ak- prefix
content/commands/ak-{skill-name}.md

IMPORTANT: Naming Rules

1. agent-kit commands MUST use ak- prefix: All commands in content/commands/ must be prefixed with ak- to avoid conflicts with user-created commands.

   • ✅ content/commands/ak-create-plan.md → /ak-create-plan
   • ❌ content/commands/create-plan.md → conflicts with user commands

2. No command/skill name conflicts: Command names must not conflict with existing skill names in the same scope.

Command template:

---
description: {One-line description of what command does}
arguments:
  - name: {arg-name}
    description: {What the argument is for}
    required: false
---

Use the {skill-name} skill to help the user {accomplish task}.

Follow the {skill-name} skill instructions in @skills/{skill-name}/SKILL.md exactly.

Key steps:
1. {Step from skill}
2. {Step from skill}
...

See assets/command-template.md for the full template.

Step 7: Validate with skill-validator

Before finalizing, run the skill-validator to ensure the skill meets all requirements:

User: Validate my new skill at {path}

Claude: [Runs skill-validator checks]
[Reports any errors, warnings, or suggestions]

The validator checks:

• Frontmatter requirements (name, description)
• SKILL.md structure and token limits
• All referenced files exist
• Corresponding slash command exists
• agent-kit commands use ak- prefix (for content/commands/)
• No command/skill name conflicts

Only proceed if validation passes with no errors.

Step 8: Test the Skill

1. Ask Claude something that should trigger it
2. Verify it activates correctly
3. Check the output quality
4. Iterate on instructions

Frontmatter Requirements

---
name: skill-name              # Required: lowercase, hyphens, max 64 chars
description: What and when    # Required: max 1024 chars, include trigger words
license: MIT                  # Optional: license type
metadata:                     # Optional: additional info
  author: your-name
  version: "1.0.0"
---

Name Rules

• Max 64 characters
• Lowercase letters, numbers, hyphens only
• No spaces or underscores
• Cannot contain "anthropic" or "claude"

Description Best Practices

The description is critical for discovery. Include:

1. What the skill does
2. When to use it (trigger words)

❌ Bad: Helps with documentation ✅ Good: Generate API documentation from code. Use when creating docs, OpenAPI specs, or README files for libraries.

Progressive Loading

Skills use 3-level loading to stay efficient:

Keep SKILL.md under 5000 tokens. Move detailed content to references/.

Bundled Resources

assets/ - Templates and Data

# In SKILL.md
See [assets/template.md](assets/template.md) for the format.

Use for:

• Document templates
• Configuration examples
• Data schemas

references/ - Extended Documentation

# In SKILL.md
For advanced usage, see [references/advanced.md](references/advanced.md).

Use for:

• Detailed examples
• Troubleshooting guides
• API references

scripts/ - Executable Code

# In SKILL.md
Run the validation script:
\`\`\`bash
./scripts/validate.sh
\`\`\`

Use for:

• Validation utilities
• Code generation
• Data processing

Scripts execute without loading into context - only output is captured.

Common Patterns

Workflow Skill

For multi-step processes:

## Workflow

1. **Phase 1: Discovery**
   - Scan project structure
   - Identify relevant files
   
2. **Phase 2: Analysis**
   - Parse content
   - Extract patterns
   
3. **Phase 3: Generation**
   - Apply template
   - Write output

Reference Skill

For domain knowledge:

## Quick Reference

| Term | Definition |
|------|------------|
| ... | ... |

## Detailed Reference

See [references/full-guide.md](references/full-guide.md)

Tool Skill

For specific capabilities:

## Usage

\`\`\`bash
{command} [options]
\`\`\`

## Options

| Flag | Description |
|------|-------------|
| --flag | What it does |

Output

After creation, provide:

1. Path to the new skill
2. Path to the slash command
3. Validation results
4. How to test it
5. How to iterate

Created:
  Skill:   .claude/skills/my-skill/SKILL.md
  Command: .claude/commands/my-skill.md

Validation: ✅ PASSED (0 errors, 0 warnings)

To test:
1. Start a new conversation
2. Use the slash command: /my-skill
3. Or ask: "Help me with {trigger phrase}"
4. Verify the skill activates

To iterate:
- Edit SKILL.md and test again
- No restart needed - changes take effect immediately

Examples

Example: Create a code review skill

User: Create a skill for reviewing React components

Claude: [Asks clarifying questions]
- What aspects to review? (performance, accessibility, patterns)
- Any specific rules or style guide?
- Should it suggest fixes or just identify issues?

[Creates skill structure]
.claude/skills/react-review/
├── SKILL.md
├── assets/
│   └── checklist.md
└── references/
    └── patterns.md

Example: Create a documentation skill

User: Create a skill for writing JSDoc comments

Claude: [Creates skill with template]
.claude/skills/jsdoc-writer/
├── SKILL.md
└── assets/
    └── jsdoc-template.md

Template Reference

See assets/skill-template.md for the starter template.

Validation

Before finalizing, run skill-validator to verify:

• Frontmatter has required fields (name, description)
• Name follows rules (lowercase, hyphens, no reserved words)
• Description includes what AND when
• SKILL.md is under 5000 tokens
• All referenced files exist
• Examples are concrete and testable
• Corresponding slash command exists
• Command references the skill correctly
• agent-kit commands use ak- prefix (for content/commands/)
• No command/skill name conflicts

Related Skills

• skill-validator - Validates skills after creation (invoked automatically)
• doc-contents - For documentation generation
• create-plan - For implementation planning
• brainstorm - For exploring skill ideas before creating