Cost Tracking, Auth & Production Hardening

$2,847 for six hours of work. That's what I paid when a developer accidentally created an infinite loop in my AI platform. GPT-4 at $3.20 per iteration, running 891 times while I slept. The agent kept retrying a failed classification call, convinced it could eventually succeed. It never did. But my credit card kept getting charged. That morning taught me that cost control isn't a nice-to-have feature - it's life support for AI platforms. The $2,847 Wake-Up Call Here's exactly what happened. A developer was testing an agent that analyzed customer feedback. The agent was supposed to: Extract sentiment from reviews Classify issues Generate summary reports But there was a bug in the ReAct loop. When the classification tool returned an empty result (which happened for non-English reviews), the agent assumed it failed and retried. Forever. The logs told the story: 2024-01-15 14:23:15 - Agent: Classifying review text... 2024-01-15 14:23:18 - Tool: Classification failed - no result 2024-01-15