Write down the last 3 things you pasted (or would paste) into an AI tool. Label each: public / internal / confidential. You're done when you've named the one paste you'd redo differently — most people find one.
How-to · INF · INF.5
Classify before you paste — 60-second drill
Public / internal / confidential is the classification that decides where text may go; run it before every paste.
Worked example
The paste decision isn't about the tool; it's about the data. Three buckets: public (fine anywhere), internal (approved tools only), confidential (approved tools with a reason, or nowhere). Sixty seconds of classification prevents the leak no setting can undo.