Most marketing teams learn their CAC doubled on Tuesday by reading the Monday dashboard next week. The 90-day pipeline that catches it within hours: GA4 + Meta + Google Ads into a Sheet, nightly Gemini call with a 14-day baseline and a name-the-cause prompt, red/yellow severity to Slack. Includes the actual prompt, the n8n JSON, and a real Tuesday alert.
Smart Bidding has no signal at $50/day. Here's the Claude-managed guardrail system I run instead — bid floors, 7-day ROAS checks, auto-pause, and budget redistribution to winners.
