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Bruno Ashford @brunoashfordSubscribeModule 5 · Lesson 5.1 · 10 min
What a Skill Is
Understand a skill as a reusable, standard procedure that Claude loads only when the task needs it.
Use ← → to move. The marker highlights text and the pencil draws on the slide; navigation locks while you annotate. Undo removes the last mark, Esc exits.
1See the anatomy of a skill
A skill is a folder named after the skill, containing a file called SKILL.md. The top of the file is a small block called frontmatter with a name and a description. Below it are plain written instructions. That is all a basic skill needs.
Create .claude/skills/complaint-reply/SKILL.md with this content:
---
name: complaint-reply
description: Drafts a reply to a customer complaint in our voice. Use when the user shares a complaint email, review or message and asks for a response.
---
# Complaint reply
1. Read the complaint and identify the real issue.
2. Check the client brief if there is one.
3. Draft a reply, never send it.2Know where skills live
Project skills go in .claude/skills/<skill-name>/SKILL.md inside your Company folder, so they apply to that business and can be shared with your team. Personal skills go in ~/.claude/skills/<skill-name>/SKILL.md and follow you across every project.
3Understand the two ways a skill runs
Automatically: when your request matches the description, Claude loads the skill on its own. Directly: you type / followed by the skill name, for example /complaint-reply. This is why the description matters so much. It is the trigger.
4Know why skills are cheap to keep
Only the short name and description sit in Claude's context all the time. The full instructions load only when needed. So unlike CLAUDE.md, you can have dozens of skills without crowding the desk you learned about in Module 4.
5See what you already have
Type /skills in Claude Code to list the skills available in this session, including a few that ship with Claude Code. Yours will appear here once you create them.
/skillsEvery business has a handful of tasks done again and again: the proposal, the complaint reply, the Friday report. Each time someone does it slightly differently, and each time the quality depends on who is in the office. You have probably tried to fix this with an SOP document. Be honest: when did someone last open it?
A skill is an SOP that actually runs. It is a folder with a SKILL.md file: a short description of when to use it, then the steps, rules and examples. Claude sees the description of every skill you have, and loads the full instructions only when a task matches. You can also call a skill directly by typing a slash and its name.
Key points
- A skill is an SOP that runs: a folder with a SKILL.md file.
- Frontmatter holds the name and the description.
- The description decides when Claude uses it automatically.
- You can also call it directly with /skill-name.
- Only the description stays loaded, so skills do not crowd context.
Avoid
- Writing a vague description like "helps with emails" so it never triggers.
- Putting a whole process in CLAUDE.md instead of a skill.
- Saving the file with the wrong name. It must be SKILL.md inside a folder.
- Building a skill for a task you only do once a year.
Maria's clinic answers about 15 online reviews a month. Some replies were warm, some defensive, and one accidentally mentioned a treatment, which is a privacy problem. She turned her reply rules into a skill: thank the reviewer, never confirm they are a patient, move any complaint to a phone call, sign off as the practice manager. Now any receptionist pastes a review and asks for a reply, and the output is consistent and safe.