testing-llm-features

Builds an offline eval suite for LLM-powered features: golden reference cases per prompt template, deterministic scoring where possible, a regression gate on prompt, model and retrieval changes, and CI wiring with promptfoo, Vitest or deepeval. Use when a product ships prompts, agents or RAG, when a model or prompt upgrade needs a regression check, when LLM output is currently verified by someone eyeballing it, or when asked how to test a feature whose output is non-deterministic.