Ten Things to Wire Up Before an Agent Touches Production

A developer deployed a customer-support agent that got stuck in a retry loop with a CRM tool. No hard circuit breaker. It spent six hours overnight repeating the same broken call while he slept, and he woke up to roughly a $4,200 OpenAI bill for doing nothing useful. That's the failure mode. Not a dramatic hack — a boring loop with no external stop. Roughly 95% of enterprise generative-AI pilots in 2025 delivered no measurable return, and almost none of those were model failures. Teams optimized the brain and skipped the nervous system. A read-only chatbot is a wiki with better search. A deployed agent does things — writes to a database, calls an API, refunds a customer. That shift from reading to doing is where pilots die. The useful mental model: treat the LLM as a fallible kernel, not a magic box. You don't trust a kernel blindly. You wrap it in checks, limits, and a way to roll back. Agents break three assumptions your ops playbook depends on Non-determinism. The same input can produce different actions on different days. An agent succeeds Monday and fails on the identical request Tuesday. Call it ghost debugging — the bug won't sit still long enough to catch. Design for a 3% to 15% tool-call failure rate as a normal state, not an exception. Cost grows with loop length, not request count. This is the mechanism most guides skip. The agent loops: think, call a tool, read the result, think again. Frameworks append every step and every tool error to the running history, then resend the whole cumulative log on the next call. Token use grows quadratically. A 20-step loop is not twice a 10-step loop — each step re-pays for everything before it. Related trap: past roughly the 40% context-fill mark, answers get worse. Load the window with tool definitions and raw JSON and you're doing your real work in the dumb zone. Every tool you connect widens the blast radius. Which brings us to the controls. Four controls the agent cannot touch Wire these before you touch agent logi