What problem does it solve? Measuring whether an LLM application actually works well is hard: single metrics mislead, regressions slip into production, and open-ended outputs resist simple scoring. This Skill provides a complete evaluation methodology covering automated metrics, LLM-as-judge patterns, human annotation, RAG pipeline scoring, and CI/CD regression detection. ## Core Features & Use Cases - Automated Metrics: Implementations of BLEU, ROUGE, BERTScore, perplexity, and custom metrics like groundedness and toxicity. - LLM-as-Judge: Pointwise, pairwise, and rubric-based judging with position-bias mitigation via order swapping and structured JSON output. - RAG Evaluation: RAGAS metrics (faithfulness, answer relevancy, context precision/recall) to diagnose retrieval and hallucination issues. - Agentic & Structured Output Evaluation: Task success rates, tool-use accuracy, step efficiency, and Pydantic schema compliance checks. - Use Case: Before deploying a prompt change, run your eval suite in CI, compare against the baseline commit, and automatically fail the build if any metric regresses by more than 5%. ## Quick Start Ask the AI to set up an evaluation suite with RAGAS metrics and an LLM-as-judge pairwise comparison for your RAG chatbot's test cases.