What problem does it solve? Measuring the quality of LLM applications is difficult because traditional software tests cannot capture fuzzy qualities like accuracy, coherence, and groundedness. This Skill provides a systematic framework for evaluating LLM outputs so you can detect regressions, compare models, and validate prompt changes before deployment. ## Core Features & Use Cases - Automated Metrics: Compute BLEU, ROUGE, BERTScore, perplexity, and retrieval metrics like MRR and NDCG for RAG pipelines. - LLM-as-Judge: Use stronger models to score responses pointwise, pairwise, or against reference answers. - Human Evaluation & A/B Testing: Structure annotation tasks, measure inter-rater agreement with Cohen's kappa, and run statistically rigorous A/B tests with t-tests and effect sizes. - Use Case: Before shipping a prompt change to your RAG chatbot, run the evaluation suite against a golden dataset of 50 question-answer-context triples, detect any regression in faithfulness, and route low-scoring answers to human reviewers. ## Quick Start Ask the AI to evaluate your LLM application by running automated metrics like BLEU, BERTScore, and groundedness against your test dataset and report any regressions compared to the baseline.