Skills - All You Need to Know

Hey Peeps,

Krishna Rao runs finance for Anthropic — a company that went from $9B to over $30B in annualised revenue in four months.

His team did not hire 50 new people to keep up.

They built Skills. Over 70 of them. One Skill alone — called MFR — now produces their entire monthly financial review. 90 to 95% ready before any human touches it.

This isn't just Anthropic. PwC found that workers with AI skills earn 56% more than peers in the same roles without them. The World Economic Forum put it plainly: AI skills are becoming a partial equaliser in hiring — shifting attention away from credentials toward demonstrable, current capabilities.

So today, let's start from the very beginning. What are Skills, what's inside them, and how do you actually use them.

First — What is a .md file?

When a Skill is created, it generates a .md file. Most people see that and freeze. Don't.

A .md file is just a plain text document. Think of it like a Word document — except anyone (or any AI) can open and read it without needing Word installed. That's the only thing special about it.

It uses simple symbols to add formatting:

You can open a .md file on Windows with Notepad, on Mac with TextEdit, on mobile with any text editor. Or just rename it from .md to .txt — and it opens like a normal text file.

That's it. No magic. Just a text file with a different label.

So what actually goes inside a Skill?

Think of a Skill's .md file as a briefing document. Before the conversation even starts, the AI reads it — and already knows the task, the approach, what good output looks like, and what to avoid.

Inside, you might find:

When you type /newsletter or /finance in Claude, the right Skill fires automatically. No uploading. No re-explaining. The AI already has the briefing.

That's the magic of a Skill — memory with a trigger.