Master retrieval-augmented generation, vector databases, embeddings, and semantic search systems.
RAGAS for fast experiments, DeepEval for CI gates, TruLens for production tracing. The metric-by-metric comparison plus the 2026 production thresholds to set.
Recall converges at 95-99% across HNSW engines, so cost at scale is throughput-per-dollar. ScyllaDB hits 252K QPS at 2ms P99 on 1B vectors. Here's the math.
Jina Reranker v3 hits 81.33% Hit@1 at 188ms, the only top-tier sub-200ms model. The latency and NDCG breakdown across Cohere, Voyage, Jina, and BGE.
Bad extraction poisons every downstream embedding. The honest breakdown of Reducto, LlamaParse, Unstructured, and Docling on tables, compliance, and price.
PageIndex hits 98.7% on FinanceBench with no embeddings and no vector DB. Here's how the LLM-reasoned TOC tree works, where it breaks, and when to migrate.
Cursor, Notion, and Linear standardized on Turbopuffer for one reason: object storage cuts vector DB cost 10x at scale. Here's the migration playbook, and when Pinecone still wins.
Chroma tested 18 frontier models across long contexts. All of them degraded, 30%+ accuracy drops when the answer sits mid-document, 7.9% loss from length alone. Here's the cap and the compaction loop we ship.
Andrej Karpathy's LLM Wiki compiles raw sources into a maintained knowledge base before queries ever arrive: eliminating embedding drift, chunk-boundary errors, and retrieval noise. Here's when it beats RAG and when it doesn't.
Traditional RAG pipelines hit 34% accuracy on complex queries. Agentic RAG's agent-controlled retrieval loop, with routing, grading, and self-correction, pushes that to 78%. Here's the architecture and how to build it.