principle-prove-it-works

1# Prove It Works
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3Verify every task output by checking the real thing directly. Do not infer from proxies, self-reports, or "it compiles."
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5**Why:** Unverified work has unknown correctness. Indirect verification (file mtimes, output freshness, agent self-reports, cached screenshots) feels cheaper than direct observation. Acting on a wrong inference costs far more than checking the source.
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7Check the real thing, not a proxy:
8- Check process liveness directly, not indirectly through derived state
9- Read the actual value, not a cached or derived representation
10- When verification fails, suspect the observation method before suspecting the system
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12## Script the check when you can
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14The strongest proof is a deterministic script that re-runs the same comparison, not a one-time eyeball. Write the script, run it, and keep its output as an artifact a reviewer can re-run instead of trusting your word.
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16Keep the artifact visible for the human. Commit it only for large or complex work where the trail has to be auditable later, like a big port or migration (the **show-me-your-work** skill).