I’ve typed the same instructions into Claude at least 50 times: how I want my newsletter written, my report format, my tone, my rules—every single session. In this video, I show how Claude Cowork Skills fixes that. A skill is basically one file that Claude “inherits” permanently, so you stop re-explaining and stop reprompting. I walk through where to access skills (the Cowork desktop app), how skills live inside plugins, and why the “Customize → Skills” section is the real place to start if you want to build your own workflow. Then I demo what I actually use day-to-day: my email newsletter skill. We open the skill file, break down how it’s structured, and I edit it live using the built-in Skill Creator—adding a new “community wins” section without rebuilding the whole thing. After that, I build a brand new running accountability skill from scratch, where Claude asks 10 clarifying questions before generating the skill. The key takeaway: skills aren’t just prompts—they’re reusable, updatable workflows, and you can test them with Cowork’s evaluation system to see how they perform with and without the skill enabled.