The Driftproof receipt for code-review-and-quality on Claude Opus 5, from Report 011, dated 2026-09-23, and what it can say.
code-review-and-quality on claude-opus-5
Not enough draws
Not enough draws to conclude at this effect floor.
Draws needed: 9 draws per arm (case severity-labeled-findings), with the spreads held.
Skill token cost: +6975 input and +507 output tokens per call against no skill (measured, grading excluded).
The two arms
| arm | mean | spread across cases | cases |
|---|---|---|---|
| with the skill | 0.901 | no spread recorded | 1 |
| without the skill | 0.862 | no spread recorded | 1 |
No lift is stated for a state that did not measure one. A spread is the sample standard deviation of the per-case means: a descriptive spread with no coverage probability. The verdict above reads each case's two bands, not these aggregates.
What was verified
receipt_hash verified when this page was built from receipts/report-011/code-review-and-quality-claude-opus-5-2026-09-23.json; run.transcripts records retained-local.
Receipt hash: d7bd2fcd3dbea881a53581022cea4a311ed9e75b457aa6d91a7c4d1c3aaaecd0
Check this file yourself
validate shows that this file is unchanged since it was sealed. It does not show who made it or who sealed it.
curl -fsSLO https://raw.githubusercontent.com/driftproofhq/driftproof/main/receipts/report-011/code-review-and-quality-claude-opus-5-2026-09-23.json
npx driftproof@0.28.0 validate code-review-and-quality-claude-opus-5-2026-09-23.json