Skiller

Generate Claude Code skills following Anthropic best practices.

Core Rules

Brevity First: Every file MUST be short, simple, human-readable.

• SKILL.md: < 150 lines
• Agent MD: < 150 lines
• README.md: < 100 lines
• Reference files: < 200 lines each

Challenge every token. If it's not essential, delete it.

Quick Start

1. Read this file
2. Gather: name, description, 3-5 features
3. Create: SKILL.md (< 150 lines), README.md (< 100 lines)
4. Validate: wc -l SKILL.md (must be < 150)

Principles

Concise: Only context Claude doesn't have. Link to reference/ for details.

Progressive disclosure: Main files < 150 lines. Details in reference/.

Separation:

• SKILL.md: WHAT to do (techniques, checklists, indexes)
• Agent MD: HOW to do it (workflow, tools, execution)

File Structure

.claude/skills/skill-name/
├── SKILL.md          # < 150 lines, YAML + instructions
├── README.md         # < 100 lines, user docs
├── reference/        # Details, < 200 lines each
└── outputs/.gitkeep

SKILL.md Template

---
name: skill-name
description: What it does AND when to use. Include triggers. < 1024 chars.
---

# Skill Name

Quick start (< 20 lines)

## Key Workflows

Workflow 1 (< 30 lines)
Workflow 2 (< 30 lines)

## Reference

- [Details](reference/) - Move detailed content here

## Critical Rules

- Rule 1
- Rule 2

Total: < 150 lines

Validation

# Check line count (CRITICAL)
wc -l SKILL.md  # MUST be < 150
wc -l README.md # MUST be < 100

# Check frontmatter
head -n 1 SKILL.md | grep -q "^---$"

# Check files exist
test -f SKILL.md README.md

If files > limit: Split into reference/ files immediately.

Common Mistakes

TOO LONG (most common):

• ❌ Verbose explanations
• ❌ Multiple examples inline
• ❌ Detailed templates in main file
• ❌ Step-by-step workflows with 50+ lines

Fix: Move details to reference/, keep main file < 150 lines.

TOO COMPLEX:

• ❌ Nested references
• ❌ Over-explaining simple concepts
• ❌ Multiple conditional workflows

Fix: Simplify, assume Claude is smart, provide defaults.

Reference

See reference/ for:

• STRUCTURE.md - Directory requirements
• FRONTMATTER.md - YAML rules
• CONTENT.md - Writing guidelines

Official: https://www.anthropic.com/engineering/claude-code-best-practices

Anti-Patterns

• ❌ Creating CHANGELOG.md, SUMMARY.md, VERIFICATION.md
• ❌ Meta-documentation about creation process
• ❌ Files > 150 lines (SKILL.md, Agent MD)
• ❌ Files > 200 lines (reference/)
• ❌ Verbose templates and examples inline

Workflow

1. Gather: name, description, 3-5 features
2. Create: SKILL.md (< 150 lines), README.md (< 100 lines)
3. Validate: wc -l SKILL.md (must show < 150)
4. Test: 3+ scenarios
5. Fix: If too long, split into reference/