Stop Time Machine from eating your disk when you run AI agents (macOS) — asimov + exclusions walkthrough
Written together with my AI coding agent — it's what actually diagnosed and fixed this on my machine, then drafted this writeup and the prompt below. Sharing it in that spirit, not pretending I hand-typed every word.
⚠️ Correction (2026-07-03): the folder-exclusion approach in this walkthrough (asimov /tmutil addexclusion) only slims your final backed-up output — what gets copied to an external backup drive. It does NOT reduce ongoing disk usage from macOS local snapshots, which is the thing that actually fills your disk during agent