The Driftproof receipt for grill-me on Claude Sonnet 5.5, dated 2026-11-01, and what it can say.
grill-me on claude-sonnet-5-5
Regressed
A case separated downward under the band rule. That is a separation detected under the rule, not proof that the skill moved the score.
Skill token cost: +65 input and +359 output tokens per call against no skill (measured, grading excluded).
The two arms
| arm | mean | spread across cases | cases |
|---|---|---|---|
| with the skill | 0.678 | ± 0.201 | 3 |
| without the skill | 0.749 | ± 0.153 | 3 |
Lift -0.071, ± 0.252. 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.
This receipt also reads the skill against a same-length placebo. Report 017 shows that reading.
What was verified
receipt_hash verified when this page was built from receipts/report-017c/campaign-1/9ad7ac527a21f178392b4ae9d146922b7ad58ee6ca8dcef4f8d5172f95cdb027.json; run.transcripts records retained-local.
Receipt hash: ad5aacbe99af3e9356543dc4efe0760dfcf7300aae59a5e173369eaa136e4e96
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-017c/campaign-1/9ad7ac527a21f178392b4ae9d146922b7ad58ee6ca8dcef4f8d5172f95cdb027.json
npx driftproof@0.27.0 validate 9ad7ac527a21f178392b4ae9d146922b7ad58ee6ca8dcef4f8d5172f95cdb027.json