Debugging Vector Retrieval Failures & Cosine Similarity Threshold Inaccuracies

Deep 2,000+ word technical guide on evaluating RAG chunking strategies, vector cosine distance calibration, Cohere reranking, and citation coverage auditing.

1. Diagnosing RAG Context Retrieval Failures

RAG applications frequently produce hallucinated answers due to two distinct failure modes: 1) Low-density chunking where target facts are fragmented, and 2) Un-calibrated cosine distance thresholds that pull irrelevant vector neighbors into the context window.

2. Applying Reranking for Precision Context Filtration

Integrate a secondary reranking step to filter vector store candidates prior to prompt construction.