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LLMs, GenAI, RAG, agents, evaluation · insight-1596

Pilot an annotation guide on 30 items and treat low agreement as a spec defect

Evidence type
practitioner heuristic
Difficulty
medium
Roles
Data scientist, Applied AI
Industries
cross-industry

Summary: situation, action, reason, boundary

  1. Situation

    Two annotators label LLM outputs for "helpfulness" and agree only slightly better than chance.

  2. Action

    Before scaling, have two or more annotators label 30 items, list each disagreement and what rule would settle it, add decision rules and worked edge cases to the guide, then re-pilot until agreement is stable; adjudicate remaining disagreements with a third reader and keep both original labels.

  3. Reason

    Disagreement between careful annotators usually points to an under-specified criterion, and fixing the guide is cheaper than relabelling thousands of items.

  4. Boundary

    Rubric-based human evaluation of generated text.

Symptom or risk

Teams blame annotators or average the labels, which bakes an ambiguous definition into the metric and into any judge calibrated against it.

Exceptions

Genuinely subjective preference tasks will keep some disagreement; report it instead of forcing consensus.

Trade-offs

One or two extra rounds before labelling at scale.

Pitfalls

Pilot items that are all easy; include borderline cases.

Lessons and concepts