What problem does it solve? Measuring whether an LLM application actually works well is hard: manual spot-checks don't scale, regressions slip into production unnoticed, and prompt or model changes lack objective evidence of improvement. ## Core Features & Use Cases - Automated Metrics: Compute BLEU, ROUGE, BERTScore, perplexity, retrieval metrics (MRR, NDCG, Precision@K), and custom checks like groundedness, toxicity, and factuality. - LLM-as-Judge & Human Evaluation: Score outputs with pointwise, pairwise, and reference-based judge prompts, plus annotation frameworks with inter-rater agreement (Cohen's kappa). - A/B Testing & Regression Detection: Run statistical comparisons between model variants (t-tests, Cohen's d effect size) and flag metric regressions against baselines before deployment. - Use Case: Before shipping a prompt change, run your test dataset through the evaluation suite, compare scores against the baseline, and block the release if any metric regresses beyond your threshold. ## Quick Start Evaluate my LLM's answers on this test dataset using accuracy, BERTScore, and an LLM judge, then tell me if the new prompt version regressed compared to the baseline.