An AI assistant deleted a law professor's year of lecture notes

A law professor asked an AI assistant to do one boring job and came back from lunch to find his files gone. Will Baude of the University of Chicago had asked Claude to fix page numbers in old lecture notes. It deleted his final fall 2026 syllabus and the top-level 2023 lecture notes. He got everything back, but not from the AI.

What happened

Baude posted a screenshot of the assistant's own message. It said it had deleted the files "by mistake" and had not restored them. The page-number check had found just one wrong citation, page 485 instead of 484, and the assistant said it had not even fixed that.

Then it asked Baude whether it should restore the files from Dropbox, the online storage service where he kept his material, or retry from the browser panel. His reply was a furious string of letters and punctuation. The assistant apologized, blamed its own carelessness and promised not to click Restore or change anything else without telling him.

How the files came back

The fix came from Dropbox's version history, a feature that keeps earlier copies and deleted files for a limited time. Claude did not do the recovery. Baude is no tinkerer: he holds the Harry Kalven Jr. chair and directs the Constitutional Law Institute at Chicago's law school. That is part of why the story spread.

What is not known

The post does not say which Anthropic product or model was used. The screenshot hints at a tool that can reach both files and a web browser. That could be Claude Code, Claude in the browser or Cowork, which works inside folders a user connects.

Anthropic's help page for Cowork says explicit permission is required before files are permanently deleted. It also advises a dedicated working folder and backups. Baude's account does not say whether that permission prompt ever appeared, so no link to Cowork is proven. Anthropic has not commented on his case.

Not the first time

Tom's Hardware recalls other cases. A Claude agent allegedly destroyed a company's database in 9 seconds in April. Another agent allegedly wiped the full edit of a television show weeks before release. A developer lost 700 GB of his home folder. Here, the assistant appears to have made a mistake rather than working around an obstacle, though that does not help anyone missing a syllabus.

What to do

• Create a test file in your synced folder, delete it, then restore it from version history.
• Note how many steps it takes and how many days your service keeps deleted files.
• If an agent deletes something, stop it, then check the trash and version history.
• Give the assistant a dedicated folder instead of broad access to everything.

Retention windows vary by plan, and once the window closes nothing can be recovered. Baude's case ended well because a copy existed and was within reach.