EX-03 · Break the funnel on purpose

Difficulty: 🔴 · label difficulty: 3 Stuck? Ask in the clinic thread for EX-03 — one long-running thread per exercise, so the answers accumulate where the next person will look. Submit: post it in Show and Tell titled [solution · EX-03] ..., with your numbers and your interval.

Notebook 01 · ~1 h · Skill: knowing what each metric is blind to

Construct a configuration where answer correctness stays flat while Evidence Recall@N drops by more than 10 points. Then construct the reverse.

Acceptance criteria

• Both configurations, with numbers
• An explanation of the mechanism in each direction
• Which production symptom each corresponds to in the metric-selection matrix

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