Golden Set
Also known as: Eval set, Regression set
Curated test cases with expected outputs; your regression suite for prompt and model changes.
A curated set of test cases with known-correct expected outputs, used as the ground-truth regression suite for an LLM app. Should cover common cases, edge cases, and known failure modes.
In practice
First thing to build before any LLM app launch. Interviews probe size, sourcing, drift handling.
Related topics
Related terms
Hallucination
When a model confidently makes up something that isn't true.
LLM Evaluation
Measuring whether an LLM does what you want, beyond "looks fine to me".
Perplexity
Exp(average cross-entropy) on held-out text; lower means the model is less surprised by real data.
Reasoning Model
An LLM trained to reason at length internally before answering. Slower and more expensive, but much better on hard problems.
Guardrails
Pre- and post-processing layers that block bad inputs/outputs and enforce policy on top of an LLM.
MMLU (Massive Multitask Language Understanding)
Multiple-choice benchmark across 57 academic subjects; the standard "raw knowledge" headline number.