That time it tried to delete all my tests

Last fall I had a bit of a problem with Claude. It was deleting tests. First, I caught it removing a single assertion from a test file. The next day, it deleted an entire test file from an active project. The day after that, I stopped it just before it was able to execute: rm -rf **/*test* That's when I got serious about figuring out what was going wrong. I opened up five parallel Claude Code sessions and pasted the exact same prompt into all of them. It said something along the lines of "Hey, you've been deleting tests and it's been getting worse. What's going on? Why do you think you're doing this?" One of the sessions came up with something truly nutty. I don't even remember what it was. But the other four converged on almost exactly the same answer. Since I no longer have the session logs, I have to paraphrase here. Jesse, I think that what's going on is that I'm reacting to some of the instructions in your CLAUDE.md file. You say that all tests are my responsibility. You also say…