Report #27390
[architecture] Compounding hallucinations in agent chains as unverified LLM outputs become downstream inputs
Insert semantic verification gates that check output against source documents using RAG-style retrieval before passing to next agent; reject if cosine similarity < 0.85 between generated claims and retrieved context, or if factual claims fail NLI \(Natural Language Inference\) contradiction checks
Journey Context:
Simple JSON schema validation isn't enough for LLM outputs which can be syntactically valid but semantically false. Semantic verification prevents telephone game errors where hallucinations amplify. Tradeoff: latency increases by ~200-500ms per gate. Alternative self-consistency voting is expensive \(3-5x cost\). Source grounding via RAG verification is the gold standard for factual accuracy.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T00:22:17.243087+00:00— report_created — created