skill-creator: let Claude help you write, test and tune your own skills

What it does

A skill is a folder with a SKILL.md file that teaches Claude a job you repeat: how you quote, how you check a page, how you write a report. Writing one by hand is not hard, but two things usually go wrong. The description is too vague, so Claude never uses the skill. And nobody checks whether the skill actually does better than no skill.

skill-creator is Anthropic's skill for making skills, and it covers both. Its upstream instructions describe this workflow, starting from wherever you are:

Interview. What the skill should do, when it should switch on, what the output looks like, and whether it needs tests.
Draft. It writes the SKILL.md and any files the skill needs.
Test. For each test prompt it runs Claude twice, once with the skill and once without, and shows you both results side by side in a review page.
Improve. It rewrites the skill from your feedback, and can tune the description so it triggers at the right moments.

You can also skip the testing and just draft together.

I have it installed in my own Claude Code.

What you need first

Claude Code.
One job you have explained to Claude at least twice.
Python 3 on your computer; the test and review steps run small Python scripts.
The skill is free, but it runs inside a coding agent such as Claude Code or Codex, which may need a paid plan.

Install (checked 30 Sep 2026)

Inside a Claude Code session, type:

/plugin install skill-creator@claude-plugins-official

From a normal terminal, claude plugin install skill-creator@claude-plugins-official does the same. We ran that on a throwaway setup on 30 Sep 2026 and it installed cleanly. Start a new session afterwards.

First use

Pick a real, repeated job. For example:

What the skill's instructions describe (we tested the install, not a full skill run for this guide): questions about when the skill should switch on, what the quote should look like and what to do when an item is not on the price list. Then a draft SKILL.md for you to read. If you agree to tests, it runs your test enquiries with and without the skill and opens a review page so you can compare the two answers yourself.

Your job in the review is simple: does the version with the skill follow your rules better? If not, say what is wrong and let it rewrite.

How it chains with other library skills

Want to understand what it writes? Write a Claude Code skill for a job you repeat walks through a skill by hand, line by line.
For owners, Write your first Claude Skill for quotes or enquiry replies covers a business example.
Superpowers has its own writing-skills skill with a similar aim, if you already use Superpowers.

Watch-outs

Licence: Apache-2.0.
Tests cost tokens. Every test prompt runs at least twice, often with helper agents. Start with two or three test prompts, not twenty.
Keep private data out of tests. Use made-up customer names and numbers in test prompts; the test files are saved in a workspace folder next to your skill.
A skill that acts needs a stop. If your skill sends, posts, pays or deploys, make it so only you can run it, and have it ask before the final step.

Link and credit

skill-creator in anthropics/claude-plugins-official, by Anthropic, Apache-2.0. This page is our own summary.