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Agents2026-06-19 · source-backed

Evaluator bias is contagious in multi-agent systems.

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A new paper on "Contagion Networks" (arXiv:2606.20493) shows that when LLMs serve as evaluators inside multi-agent systems, their systematic biases propagate through the network rather than staying local. A single biased judge can contaminate downstream agent decisions. If you run LLM-as-judge pipelines or agent self-improvement loops, this argues for diversifying or auditing your evaluator agents, because one bad judge poisons everything it touches.

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