The Driftproof receipt for grill-with-docs on Claude Sonnet 5.5, dated 2026-11-01, and what it can say.
grill-with-docs 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: +98 input and +248 output tokens per call against no skill (measured, grading excluded).
The two arms
| arm | mean | spread across cases | cases |
|---|---|---|---|
| with the skill | 0.906 | ± 0.136 | 3 |
| without the skill | 0.922 | ± 0.072 | 3 |
Lift -0.017, ± 0.154. 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/bfc0fd31bf2c53d679e22d467a049c6f8a5e2209265a755d14c5d2ca68a1ef02.json; run.transcripts records retained-local.
Receipt hash: 09e0d9f8092405058e0bde94b23385ca6599266cb018f965edbe4dddedd0ab5b
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/bfc0fd31bf2c53d679e22d467a049c6f8a5e2209265a755d14c5d2ca68a1ef02.json
npx driftproof@0.27.0 validate bfc0fd31bf2c53d679e22d467a049c6f8a5e2209265a755d14c5d2ca68a1ef02.json