Claude Skills for RAG Evaluation 2026: Ragas & Phoenix
RAG evaluation with Ragas and Phoenix in 2026: build Claude Skills that catch silent retrieval failures, score faithfulness, and trace every answer to its...
Chapter 1: Why RAG Evaluation Broke in 2026 (And What Changed) There is a specific kind of failure that only shows up after a retrieval-augmented generation system ships. The demo worked. The internal pilot got compliments. Then real users arrived with real questions, and the assistant started confidently citing the wrong policy document, or answering from its own pretraining while a perfectly good source sat unretrieved in the index. Nothing crashed. No exception fired. The logs were clean. The system was simply wrong, quietly, at scale. That gap — between "it runs" and "it's right" — is what broke in...