Stuck in the Loop: Why AI Agents Retry, Oscillate, and Never Finish

An agent moving through a multi-step task needs two things it doesn't automatically have: a reliable way to know when the task is actually finished, and a reliable way to recognize when its current approach isn't working. Without both, the agent has no internal alarm bell. It just keeps acting — and if the same action keeps producing the same unhelpful result, nothing tells it to stop, change course, or ask for help. This isn't a minor implementation detail. It's a structural gap in how most agent loops are built: observe, decide, act, observe again. That loop has no natural exit condition unless one is explicitly designed in. Pattern One: The Retry Loop : The retry loop is the simpler of the two failure modes. The agent takes an action, it fails, and the agent tries the exact same action again — sometimes with trivial variation — expecting a different outcome. A few reasons this happens: Misread failures : The agent doesn't correctly interpret why the action failed, so it can't adjust its approach. It just repeats the attempt. No failure memory : Without a persistent record of "I already tried this and it didn't work," the agent has nothing to check against before trying again. Overconfidence in the plan : If the agent's internal reasoning treats the original plan as correct, it may conclude the execution was the problem, not the plan — and simply re-execute. The result is a kind of insanity loop: identical input, identical output, repeated until a turn limit, budget cap, or timeout finally intervenes from the outside. Pattern Two: Oscillation : Oscillation is subtler and, in some ways, more dangerous, because it can look like activity rather than failure. The agent doesn't repeat the same action — it alternates between two (or more) states, undoing its own progress each cycle. A classic example : An agent editing a file makes a change, then in a later step "fixes" that change back to something close to the original, believing it's correcting an error. The next cyc