1.3Markdown Body: The Execution Instructions

The body is what Claude reads when the skill is invoked. It should be structured for an AI agent, not a human reader.

Best Practices

1. Lead with a one-line summary — What does this skill do?
2. List commands in a reference table — Quick lookup format
3. Show common patterns — The 80% use cases
4. Include tips — Gotchas the agent needs to know
5. Stay under 500 lines — Longer skills bloat context; use /references/ for details

Example: A Browser-Automation SKILL.md Structure

This is the shape of the SKILL.md that playwright-cli install --skills generates (and the same shape Vibium's vibe-check skill pioneered):

# Playwright CLI — Browser Automation Reference

The `playwright-cli` automates browsers via the command line.
Snapshots and screenshots are saved to .playwright-cli/ on disk.

## Commands

### Core
- `playwright-cli open <url>` — launch browser at a page
- `playwright-cli snapshot` — save page snapshot (YAML with element refs)
- `playwright-cli click <ref>` — click element by ref (e.g. e8)
- `playwright-cli fill <ref> "<text>"` — fill input by ref
...

### Common Patterns

**Read a page:**
​```sh
playwright-cli open https://example.com
playwright-cli snapshot   # then Read the snapshot file it names
​```

## Tips
- All actions auto-wait for the element to be actionable
- Take a snapshot after navigation before interacting — refs come from snapshots

This structure works because:

• The agent can scan the command table to find what it needs
• The patterns section provides copy-paste workflows
• The tips prevent common mistakes