You are paged: the overnight batch agent has been running 6 hours instead of 20 minutes and has spent 400 dollars. Walk me through your response.

Question

Accepted Answer

First minute: kill the run and confirm billing has actually stopped, then immediately check what side effects it executed while looping, did it write records, send messages, call external APIs, because a stuck agent is not just a cost problem, 6 hours of retrying may have half-executed things that need cleanup or dedup. Then evidence: the full trace of the run is the incident record; I want where behaviour diverged from the normal 20-minute shape. The pattern is usually visible fast: at some step a tool started failing or returning something the agent could not use, and instead of stopping, it retried, rephrased, retried, each failure appending to the context, and a context full of failed attempts makes the next decision worse, so loops self-reinforce. Common mechanical causes: an upstream dependency changed or went down and the tool error was unhelpful, "error 500" tells the model nothing actionable, so it flails; the success condition became unreachable, the data it was told to find stopped existing, and nothing bounded the search; and malformed tool output that parsed but meant nothing, so the agent politely looped on garbage. The immediate fix targets whichever it was. The real work is preventing the class, because a 6-hour 400-dollar run means our controls were missing, not that the model misbehaved: hard budgets enforced by the harness, not the prompt, iterations, tokens, wall-clock, spend, this job should have died at 2x its normal envelope, so roughly 40 minutes or a few dollars; loop detection, same tool with same arguments twice triggers intervention; tool errors rewritten to be actionable so the agent can adjust or give up cleanly; a designed failure path, checkpoint state, summarise progress, alert a human, rather than retry forever; and an anomaly alert on runtime and spend per job, because a human should have been paged at minute 40, not hour 6.

Answer

The agent sent 200 duplicate notification emails while looping. Now what?

Side-effect triage: dedup and apology where needed, then the structural fix, idempotency keys on side-effecting tools and confirmation gates on externally-visible actions, so a loop can waste tokens but not repeat sends.

Answer

Why must the budget live outside the model rather than in the prompt?

A model deep in a failure loop is precisely the model least likely to follow a "stop after 10 tries" instruction, its context is polluted. Enforcement has to sit where the loop runs, in code.

You are paged: the overnight batch agent has been running 6 hours instead of 20 minutes and has spent 400 dollars. Walk me through your response.

You are paged: the overnight batch agent has been running 6 hours instead of 20 minutes and has spent 400 dollars. Walk me through your response.

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