# Anatomy of a Skill — Advanced Agent Workflows and Skills

Source: https://www.geekswithgeeks.com/en/agent-workflows/skills-anatomy

> Read and write a SKILL.md file with a name, a description and step-by-step instructions.

## A folder with a SKILL.md

A skill is a folder whose main file `SKILL.md` starts with YAML frontmatter holding a `name` and a `description`, followed by Markdown instructions. The folder may also hold scripts, templates and reference documents the instructions point to.

## Small folder, loaded on demand

A skill packages instructions and helper files. The agent sees a short description first and loads the rest only when needed.

![Three layers: description, instructions, resources.](assets/figures/agent-workflows/section-2-map.svg) — Figure 2.1 — Description, instructions and resources.

## A small SKILL.md

The description tells the agent when to use the skill. The body is the procedure. In Claude Code, project skills live in `.claude/skills/<name>/SKILL.md`.

```markdown
---
name: release-notes
description: Write release notes from merged pull requests. Use when the user asks for a changelog or release summary.
---

# Release notes

1. List merged PRs since the last tag with `git log`.
2. Group them under Features, Fixes and Chores.
3. Write one plain-language line per PR.
4. Save the result to `RELEASE_NOTES.md`.
```

## One skill, one job

Keep each skill focused on a single repeatable task. A skill that tries to cover reviews, deployments and docs gets triggered at the wrong times and is hard to maintain.

**Quiz:** Which part of SKILL.md tells the agent when to use the skill?

- [ ] The last line of the file
- [ ] The folder size
- [ ] The file extension
- [x] The description in the frontmatter

*Answer:* The description in the frontmatter. The description is what the agent reads to decide whether the skill applies.