The Cascade Problem: Why Agent Side Effects Explode at Scale
A team ships a document-processing agent. It works flawlessly in development: reads files, extracts data, writes results to a database, sends a confirmation webhook. They run 50 test cases. All pass.
Two weeks after deployment, with a hundred concurrent agent instances running, the database has 40,000 duplicate records, three downstream services have received thousands of spurious webhooks, and a shared configuration file has been half-overwritten by two agents that ran simultaneously.
The agent didn't break. The system broke because no individual agent test ever had to share the world with another agent.
