Claude Skills Collection: why it is not safe to use

What we found

Our review did not find hidden instructions, hardcoded secrets, obfuscated content, privilege escalation, or undisclosed data transfers in the inspected repository materials. The documented skills mainly read user-provided files or user-requested web pages and write results locally.

The main concern is data sensitivity. At least one skill is designed to work through an authenticated Yahoo Fantasy browser session using Claude-in-Chrome. The collection also includes household finance workflows that process private financial PDFs. Based on the inspected docs and sampled files, this access appears tied to accounts and documents the user intentionally connects, not to hidden collection or export. Even so, these workflows can place sensitive personal or account data into the skill context, which raises privacy risk if used without careful scoping.

What to do instead

Use this collection only with accounts, browser sessions, and documents you are comfortable exposing to the skill context. Prefer test or low-sensitivity data where possible. Limit access to the minimum files and pages needed, review prompts and outputs for accidental inclusion of sensitive details, and avoid connecting high-risk financial or personal records unless that access is necessary.