EVAL #006: LLM Evaluation Tools — RAGAS vs DeepEval vs Braintrust vs LangSmith vs Arize Phoenix

EVAL: LLM Evaluation Tools - RAGAS vs DeepEval vs Braintrust vs LangSmith vs Arize Phoenix By Ultra Dune | EVAL Newsletter You shipped the RAG pipeline. The worked. The CEO nodded. Then production happened. Users started asking questions your retriever never anticipated. The LLM hallucinated a return policy that doesn't exist. Your "95% accuracy" metric turned out to measure nothing useful. Welcome to the actual hard part of building LLM applications: evaluation. Here's the uncomfortable truth most AI engineering teams discover around month three: building the LLM app was the easy part.