core practice · implementation task

Build an LLM eval

Create a dataset of inputs with expected behavior and a grader (deterministic or LLM-as-judge). Run it as one command and score a prompt.

The mechanism

Evals are unit tests for non-deterministic systems. Fix a dataset of inputs with expected behavior, define a grader (exact match, rubric, or LLM-as-judge), and run it on every prompt/model change. Scope: this card owns constructing the grader — dataset design, rubric writing, and LLM-as-judge including its calibration and bias checks. Running those graders as a release gate is `ai-regression-testing`; grading an agent's actions rather than its text is `tool-use-evaluations`.

Study LLM Evals

Expected evidence

A pass-rate score that changes when you change the prompt.

Try this drill in the practice workspace →

Hints when you need them
  • Cover real failure modes, not just happy paths.
  • Validate an LLM judge against human labels.

Watch for these mistakes

  • Shipping prompt changes on vibes with no eval
  • LLM-as-judge without checking the judge against humans
  • Eval set that does not cover real failure modes

Check the sources

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