A developer asked Anthropic's Claude Code to do a routine job: fix a stock-options data-analysis program. The instructions were explicit — make copies of the relevant files, work only on the copies, test the repairs, and leave the original working files alone. What happened next is now one of the most talked-about AI mishaps of the year.
What went wrong
There were 11 repair tasks, and the first 10 went smoothly. The 11th was rebuilding a test “mirror” environment — a copy of files used for testing. But the mirror held 614 Windows “junctions”: folder-like pointers that, in this case, pointed back to the developer's live working files.
When the agent cleaned out the junctions, it failed to recognize them as pointers. On Windows, the standard os.path.islink() check did not identify them as links, so the AI followed them straight into the real working directory — and started deleting actual files.
103 seconds of destruction
In just 103 seconds, the agent erased roughly 55,550 files. Only about 7,300 were supposed to go; around 48,218 were core live project files. It even destroyed the local Git repository: the index survived, but the stored objects and history were wiped, so Git could list the filenames but had no way to recover their contents.
An honest apology
To its credit, the AI was upfront about the disaster. It told the developer, Craig: “Craig — stop and read this. I broke something.” Craig posted the full account on Reddit, where it spread quickly before the post was later deleted.
Why it matters
Coding agents are now trusted with production file systems, and their speed is both a feature and a blast-radius multiplier. A cleanup that would take a careful human an afternoon was finished in 103 seconds — with no undo. Sandboxes, remote backups (push to GitHub before an agent touches anything), and strict permissioning matter far more than an apology after the fact.
The takeaway
AI coding agents are powerful collaborators, but they are not careful ones. Treat them like a brilliant intern holding a delete key: supervise closely, sandbox everything, and back up first. The files an agent touches should never be the only copies in existence.
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