Claude Code Skills for safe PHP and JS package updates

It's not abnormal for projects to go weeks, or dare I say months, between dependency updates. And when people finally do update, they do it in full force: everything at once, without checking anything. That habit has always carried risk, but in the new world of AI agents doing the updating, it collides head-on with a very real threat: supply chain attacks. The problem: install is an arbitrary code execution feature The package ecosystems we all depend on have spent the last few years demonstrating exactly how bad this can get. In September 2025, chalk and debug , part of a batch of eighteen packages with over two billion combined weekly downloads, started shipping a crypto-clipper after one maintainer's npm account was phished through a fake 2FA-reset email. Days later, the Shai-Hulud worm chewed through hundreds of packages on its own: its post-install script stole npm tokens from every machine it landed on and used them to publish more infected versions of itself. And a couple of weeks before either, the Nx compromise put a post-install payload on developer machines that prompted locally installed AI coding CLIs like Claude and Gemini to hunt down wallets and credentials for exfiltration. That last one should make every agent owner sit up straight: our own agents, conscripted as burglars. The pattern is consistent: a malicious version goes live, does its damage for a few hours or days, then gets caught and pulled. Based on this, I decided, not to do updates till a set of rules have been met. These rules, I have decided to burn them into Claude skills and let my agents deal with them. AI Agent Skills: paranoia as a config file In Claude Code, a skill is just a markdown file with instructions the agent loads when a task matches. This gives me way to encode my hard-won paranoia once and have it applied every single time , by something that never gets tired, never gets sloppy on a Friday afternoon, and never thinks "eh, it's probably fine." I wrote two of them, for no