Agents repeating the same or near-identical actions without making progress toward a terminal state.
Agent Infinite Loops is one of the more frequent production failures in AI agent deployments. Here's how to design around it.
What it actually looks like in production
- Agent called search with progressively broader queries forever
- Two agents in multi-agent disagreed and ping-ponged
- Agent retried failing tool because the error wasn't classified terminal
Why it happens
- No max_iterations cap
- Weak termination conditions in multi-agent
- Transient vs. semantic errors not differentiated
- No loop detection at runtime
How to prevent it (vendor-neutral)
1. Hard iteration caps
2. Wall-clock timeouts
3. Loop detection (same tool, similar args, repeated)
4. Cost ceiling per run
5. Explicit termination in multi-agent protocols
How Prefactor helps detect and prevent it
Prefactor sits at the agent runtime and contributes specifically:
- Runtime guardrails that flag or block matching patterns before they land
- Continuous eval suites that catch quality regressions on every change
- Tamper-evident logs of every incident and response action
- Per-agent anomaly alerts on the signals listed below
Detection — what to monitor
- Runs at max_iterations
- Same tool repeated with similar args
- Per-run cost outliers
Response — what to do when it happens
Immediate (minutes): confirm the incident from the trace; pause the affected agent if active harm possible; hotfix the trigger.
Short-term (hours): add the failure case to the eval suite; patch the root cause; redeploy with regression validation.
Medium-term (days): root cause analysis; tighten guardrails or controls; document the incident for post-mortem and audit.
FAQ
Can agent infinite loops be eliminated entirely? Usually no — reduce frequency and severity dramatically, and contain blast radius. Aim for low, detected, and contained.
How often should we test for this? Continuously, with every change. Every reported incident becomes a test case.
Can Prefactor detect this in real time? Yes for many variants — guardrails run in-line with sub-second latency.
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