What is agentskills.io?

The open standard that makes the skills you build portable. Write a capability once, and run it on whatever tool you use next.

I keep a skill called learn in a folder on my laptop. After I edit an article, I type /learn and the agent reads what I changed, pulls the new patterns out of my edits, and updates my writing guide. I built it for Claude Code. The harness I run for Headphones.com, OpenCLAW, reads the exact same skill format. The folder I wrote for one runs on the other with no rewrite, because both speak the same standard.

That standard has a quiet little home on the internet: agentskills.io.

What it is

agentskills.io is where an open standard called Agent Skills is published. A skill is a folder. Inside it sits one required file, SKILL.md, that describes a capability in plain English: what it does, when the agent should reach for it, and what good output looks like. Around that file the folder can hold whatever the capability needs: reference notes, examples, templates, even small scripts.

The format started at Anthropic, the company behind Claude, and was released as an open standard in late 2025. "Open" is the load-bearing word. Anthropic does not own the skills you write, and the format is not locked to Claude. The same SKILL.md folder is now read by Claude Code, OpenCLAW, OpenAI's Codex, Cursor, Gemini's command-line tool, and a couple dozen other products. You can read the whole specification at agentskills.io; it is short enough to finish over a coffee.

Why it matters

Here is the part that matters for a CEO, and none of it is technical.

When you run AI seriously, two things end up living on your laptop: the model and the skills. The model is rented. You pay for it monthly, a better one ships every few months, and the one you lean on today will not be the one you lean on in a year. The skills are yours. Each one is a piece of how your business actually runs, captured once and reusable forever.

The open standard is what keeps that second pile from evaporating every time the tools move. Because every serious product reads the same SKILL.md format, the skill library you build this year is portable. If a sharper agent ships next spring, or you graduate from Claude Code to a harness that runs your workflows around the clock, your skills come along. You are not rebuilding from scratch; you are reconnecting what you already own.

That is why, when a CEO asks me where to invest first, I say invest in skills, not in agonizing over which tool is perfect. The model is rented. The skills are the asset you own. The open standard is the reason that sentence holds up. It is the same case I make at length in why CEOs should use Claude Code in the terminal.

What a good portable skill looks like

Take that learn skill. The folder holds a SKILL.md and a couple of supporting notes. The SKILL.md says, in plain language: read the difference between the draft and the version I shipped, find the writing patterns I changed, check them against my existing guide so nothing gets added twice, then append the new ones. Every instruction is a sentence a sharp new hire could follow on day one. None of it names a specific product.

That last point is the whole game. A good skill describes the work, not the plumbing. It says "read my recent edits," not "call this one tool's private command." When the instructions are written for a capable reader instead of a particular piece of software, any tool that reads the standard can pick up the folder and do the job. That is exactly why the learn folder I wrote for Claude Code also runs in OpenCLAW.

Common mistakes

Assuming skills are a Claude-only thing. They are not. The entire point of the standard is that a skill folder travels across tools. If you have built skills in Claude Code, you already own portable assets, whether you meant to or not.

Hard-coding the plumbing. A skill that bakes in one tool's private commands or your exact folder paths breaks the moment it moves. Describe the work in plain English and let the agent handle the mechanics.

Shopping the ecosystem instead of building in it. A growing library of skills other people have published is out there, and browsing is fine. But the leverage is in the skills that encode how your business runs, and only you can write those.

Installing community skills without reading them. A downloaded skill is a folder of instructions, and sometimes scripts, that run with your access. Read it first, or ask the agent to read it and flag anything odd, before you trust it. There is more on that risk in the OpenCLAW explainer.

Do this next

If you have never written a skill, start with the one workflow you repeated twice last week. Open a session, describe it out loud, and ask the agent to make a skill for it. The step-by-step is Make a skill in Claude Code, and the bigger picture is What are skills in Claude Code?. Build one, and you have started a library no tool change can take from you. Tell me what you named it. I love seeing the first one people build.