Async side effects can make LLM agent tests falsely fail or falsely pass

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A red-team harness for AI support bots produced misleading results because its assertions checked the helpdesk before the ticket worker had committed tickets. The author describes a test that stayed red for three days even though the agent behaved correctly. The core lesson is that asynchronous side effects should be verified by waiting for events rather than asserting on instantaneous state. Stronger checks are recommended, such as requiring exactly one ticket and scoping it by session, queue, and time window. Those checks should also poll until a deadline instead of relying on fixed sleeps. Credit goes to several readers who identified the race condition and the duplicate-ticket gap.

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