A skill is a workflow you write down once, so Claude can follow it every time the task comes up. It's a folder with a text file, SKILL.md, and Claude reads only the name and the description until a task fits. Only then does it load the rest.
Skills are on every plan, including the free one, and they work in chat, in Cowork and in Claude Code. Plugins, which are bundles of skills, need a paid plan.
On this page
- 01 What a skill is
- 02 Skill, project or connector
- 03 How to add a skill
- 04 Build your own
- 05 My own skills
- 06 Questions and answers
- 07 Build from there
What a skill is
Without a skill, Claude guesses at the method every time you give it a task. A skill is the method written down ahead of time: the steps, the rules and examples of what the result should look like.
The folder has the same name as the skill it holds, and inside it is SKILL.md. At the top of the file are a name and a description of when to use it. Below that comes the workflow itself, written as plain text. The folder can also hold templates, examples and small scripts that Claude uses along the way.
The description is the only part Claude reads before it picks a skill. That's why you can have many skills turned on without them crowding the conversation. And that's why the description decides whether your skill gets used.
Skills follow an open standard, Agent Skills. A skill is made of text files you own. You can read them, edit them and take them with you.
Skill, project or connector
Four things in Claude often get mixed up. Each one does its own job, and they work best together.
- Project
Background that's always there in the project's chats: your audience, your offers, your files. For what belongs to one area of your business.
- Skill
A workflow that's loaded only when the task fits, and that comes along into all your chats. For what you do again and again.
- Connector
Access to your apps, like Gmail, Google Drive or your accounting. A skill can describe what Claude should do with that access. The access itself comes from the connector.
- Instructions
Rules that apply to every single answer, like putting the answer in the first line. You write them under Settings, Account, in Instructions for Claude.
A plugin is a bundle of skills for one field, sometimes with connectors inside. Plugins need Pro, Max, Team or Enterprise.
My mail agent uses two of them. Gmail is connected as a connector, and my tone lives in a skill built on emails I've sent myself. It writes the replies, and nothing is sent until I've approved it.
How to add a skill
All skills live under Customize in the menu on the left: the built-in ones, the ones from Anthropic and your own.
Turn on code execution
Under Settings, Capabilities you'll find Run code in the cloud. Skills need it, so it has to be on.
Open Customize and choose Skills
Under Discover are skills from Anthropic and from others. Under Yours are the ones you've added yourself.
Add a skill
Click + next to a skill under Discover. If someone gave you a skill as a zip file, choose Add and Upload skill.
Turn it on and try it
Open it, check that it's turned on, and click Try in chat. You can also call up a skill in a chat: type / and pick it from the list.
A skill can contain scripts that Claude runs. Only add skills from sources you trust, and read SKILL.md before you turn on a skill someone else gave you.
Anthropic's own plugins are under Plugins in the same menu. The guide 30 skills from Anthropic lists the ten I picked myself and what each of them does.
Build your own
A skill pays off when you keep correcting Claude with the same instructions. Write them down once, and you won't have to remember to explain them next time.
Start with the task in one sentence and what a good result looks like. That sentence becomes the description, and the rest becomes the workflow.
Ask Claude for a draft
Under Customize, Skills, choose Add and Create with Claude. Say what the task is, what goes in and what should come out. Claude writes the draft with you, and you edit it.
Give it your own examples
Five posts you wrote yourself say more about your tone than a description of it. For a mail agent, your own sent emails are the answer key.
Write the limit in
Write what it must never do. For example: "Write drafts. Never send. Ask if you're unsure about a price or an agreement."
Test it on three real tasks
If Claude doesn't use it on its own, rewrite the description with the words you use yourself when you ask for the task.
Keep each skill to one workflow. Several small skills work better together than one big one, and Claude can use more than one in the same chat.
On a Mac you can also record the task. In Cowork, click + in the message box and choose Record a skill. You do the task and talk along the way, and Claude suggests a skill from the recording. It works on Pro, Max and Team.
My own skills
My content agent is built from skills and scheduled runs, and each skill has its own part of the work.
Here are five of the skills I've built myself.
- ai-med-line-design
My design system: colors, fonts and the rules for how a slide, an ad or a page may look. Claude reads it before it designs anything for me.
- karrusel-builder
Builds my carousels from an approved script into finished slides, ten at most, in the sizes Instagram and Blotato need.
- caption-writer
Writes captions by three rules: the body never repeats the slides, no examples are made up, and every caption ends with one concrete action.
- line-tilbud
Proposals and pitches with my structure, my prices and my language rules, set in my own design as a PDF.
- skriv-kort-og-skarpt
Tightens emails, reports and pitches without cutting the points. You can get it free in the guide Two skills that make your AI answers shorter.
A skill is one workflow. When several skills work together, often at a set time, I call it an agent. Here's how to build the first one: Build your first agent.
Questions and answers
- Are Claude skills free?
- Yes. Skills are on every plan, including the free one, as long as code execution is on. Plugins, which are bundles of skills, need Pro, Max, Team or Enterprise.
- When should you use a skill?
- When you do the same task again and again and want it done the same way every time. A task you'll only do once is better described right in the chat.
- How do you install a skill in Claude?
- Turn on Run code in the cloud under Settings, Capabilities. Then open Customize, Skills, and click + next to a skill under Discover, or choose Add and Upload skill if you have it as a zip file.
- How does Claude know when to use a skill?
- It reads the descriptions of the skills you've turned on and loads the one that fits the task. You can also call up a skill yourself: type / in the message and pick it.
- What's the difference between a skill and a project?
- A project is background that's always there in the project's chats. A skill is a workflow that's loaded only when the task fits, and it works in all your chats.
Build from there
Start with the task you explain from scratch most often.
Skills work best when Claude knows your business. Put your tone, your offers and your clients in one place, so every new skill has something to build on.
If skills and agents should be built for your business, we set them up together in a 1:1 session. You see how I brief, what context I give it, and when it's allowed to run on its own.
