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eval-blindlisted

Compare two models, prompts, or variants without letting bias leak into the verdict. Use when: (1) deciding which model/prompt to ship, (2) grading A vs B outputs, (3) any "is the new version better" comparison. Triggers: "compare models", "which prompt is better", "eval", "A/B", "blind judge".
gnibu/bento · ★ 0 · AI & Automation · score 68
Install: claude install-skill gnibu/bento
# Blind eval Framing leaks into verdicts. If the judge knows which side is "the new one" — or if you grade the candidate's own claim instead of its behavior — you measure the framing, not the quality. Blind it. ## Steps (paste as todos) 1. **Name the decision.** One sentence: what are you choosing between, on what metric? 2. **Neutralize labels.** Rename the two arms to `A/` and `B/` — no `gpt5_run` / `new_prompt` / `v2`. Strip model/variant names from dir names, file names, and any text the judge will see. Keep the A↔B mapping in a separate note you don't show anyone. 3. **Freeze the input set.** Same prompts/dataset for both arms. Record it. 4. **Collect behavior, not claims.** Capture what each arm actually did — transcripts, files touched, outputs. Discard any "I handled this correctly" self-report. 5. **One blind judge over both sets.** A separate pass (fresh context, or a human) scores A and B on the *same* scale, having never been told which is which. 6. **Unblind last.** Only after scores are locked, reveal the mapping and read the result. 7. **Record the verdict + the mapping** so the decision is reproducible. ## Guardrails - If the judge can infer the arm from anything (a stray filename, a version string, tone), it isn't blind — fix and rerun. - Grade the same observable for both. Different rubrics per arm = not a comparison. - Ties are a result. Don't reach for the arm you hoped would win.