When you verify matters more than whether you do: hallucinations snowball through agent pipelines
A new paper formalizes the "hallucination snowball": errors injected early in multi-agent LLM pipelines don't just persist, they transform from facts to narrative to invisible, degrading detectability along the way. Checkpointing each handoff cuts survival from 58.4% to 16.2%, while end-of-pipeline checking barely helps. Verifying early beats verifying at all.