Do you have an actual rule for what you won't paste into an AI tool, or is it a gut feeling?

I keep noticing myself paste things into ChatGPT or Claude without a second thought. A contract. A customer email.

A snippet of code with an API key still in it.

I don't have a written rule. It's more of a "this feels fine" or "this feels sketchy" in the moment.

Curious whether anyone here has actually formalized this. What's on your never-paste list, and what made you draw that line?