gstack's new /eval-plan shows what a paid eval will cost before you approve it

1 day ago

gstack 1.91.79.0 to 1.91.82.0 (2026-10-11), for Claude Code users: the new /eval-plan preregisters a paid eval and projects its cost from a small pilot before you approve, and now prices its default models out of the box. Also: gstack-lane-check flags open PRs that touch your planned files, autoplan ends on a one-page owner brief, and /review gains a contributor-PR mode and a banned-terms check. https://github.com/garrytan/gstack/blob/main/CHANGELOG.md#191790---2026-10-11 https://github.com/garrytan/gstack/blob/main/CHANGELOG.md#191800---2026-10-11 https://github.com/garrytan/gstack/blob/main/CHANGELOG.md#191820---2026-10-11 https://github.com/garrytan/gstack/blob/main/eval-plan/SKILL.md

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Chapters

  1. 0:00/eval-plan
  2. 0:13Prices
  3. 0:29Lanes
  4. 0:42Owner brief
  5. 0:56/review
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/eval-plan

gstack logo

gstack’s new /eval-plan shows what a paid eval will cost before you approve it

Bars, arms, decoys, stop ruleschecklist
A $0 stub model on real inputsdry-run
About 3 runs, cost projected with an error bandpilot
/eval-planPricesLanesOwner brief/review
garrytan/gstack · CHANGELOG.md 1.91.79.0

gstack's new /eval-plan preregisters a paid eval for your product. A dry run on a free stub model checks prices and prompts. A pilot of about three runs projects the cost before you approve.

Prices

/eval-plan now prices its two default models out of the box

claude-opus-5-5$4 / $20 per MTok
gpt-6.1-sol$2 / $10 per MTok
Any model without a verified priceEVAL_PRICE_MISSING
/eval-planPricesLanesOwner brief/review
garrytan/gstack · CHANGELOG.md 1.91.80.0

Its default models, Claude Opus 5.5 and GPT 6.1 Sol, used to stop on a missing price. Both now have verified prices, so the plan runs. A model without a verified price still fails closed.

Lanes

gstack-lane-check names the open PR that touches your planned files

In-flight branch or PR overlaps your planLANE_CONFLICT
gstack-evidence verifyverified | unverified
/eval-planPricesLanesOwner brief/review
garrytan/gstack · CHANGELOG.md 1.91.79.0

gstack-lane-check compares your planned files with in-flight branch and PR, and names each overlapping PR. Evidence verify reruns a bundle's probes and marks each claim verified or unverified.

Owner brief

Autoplan ends on a one-page brief for the owner

URGENT, outside this plan · first
A plain summary
Numbered decisions · seven per page
close --plan · each draft direction becomes your decision and its date
/eval-planPricesLanesOwner brief/review
garrytan/gstack · CHANGELOG.md 1.91.79.0

Autoplan now ends on a one-page brief. Urgent items outside the plan come first, then a summary, then numbered decisions, seven per page. Closing the plan writes your decisions in.

/review

/review now reviews outside contributors’ PRs as evidence

Contributor PRs · accept, supersede or decline, credit when a diagnosis or test carries over
Banned terms · checked in every /review and /document-release diff
Plan reviews · the reality check names the review file it reads
eval-plan/SKILL.mdthe /eval-plan guide
/eval-planPricesLanesOwner brief/review
garrytan/gstack · CHANGELOG.md 1.91.79.0 · 1.91.82.0

/review now reviews an outside contributor's PR as evidence, and credits them when their diagnosis or test carries over. It flags banned terms in every diff, and the plan review's reality check names the file it reads. The /eval-plan guide has more.