Glossary · Evaluation & safety
LLM-as-a-Judge
Using a language model to score, compare, classify, or critique another system's output against a rubric.
Why it matters
It can scale evaluation of qualities that are difficult to express as exact-match tests, such as clarity or instruction adherence.
In practice
Give a separate evaluator model the task, candidate answer, reference evidence, and a structured rubric, then calibrate its scores against human-reviewed examples.
Common confusion
A judge model is not ground truth. It can be biased by order, verbosity, style, prompt wording, or shared model failures.
Related terms
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