gstack/docs/review-policy.md

Review policy: how gstack's reviews converge

This is the canonical statement of what a gstack review may block on, how the /ship review loop converges, and what the ship receipt records about it. The skills (/review, /ship) and the tools (gstack-review-scope, gstack-ship-receipt) implement it; a team's own rules should point here instead of restating it. A one-line crew rule is enough:

Review convergence: gstack review policy (docs/review-policy.md), scope knob default.

The blocking floor

A finding is blocking when it is a CRITICAL defect: it would fail a test, break production, or lose data or secrets. Everything else is below the floor: an advisory, an informational item, a test finding (category testing: a gap, a weak or flaky test), a wording or naming note, a style or simplification suggestion. Below-floor findings are reported, never fixed after pass 1 of a ship, and never earn another review pass.

Three words cover every finding, and the loop budgets by them: a blocker is the intended case gone wrong (the floor above); a should is a real bug a caller will hit inside the intended case (fixed when it is in the diff on pass 1, deferred when it is not); a nit is the rest (a named note). Two stop rules follow: if a pass's fixes grew the diff past what the request needs, cut that growth first; and the cap approves nothing, so a standing blocker is reported, never waved through.

Before a merged finding counts, the parent applies lead judgment (review/sections/review-army.md, ship/sections/review-army.md, stage 4 of the merge): a reviewer whose whole return is nits found nothing; a defect names the call site or input that reaches it, or it is a note; structure for a case nothing takes is advisory; "I would have done it differently" is not a finding; a finding that assumes a rule the repository documents otherwise is dropped with the pointer. Independent agreement between reviewers is the strongest signal.

Every reviewer prompt gstack dispatches (the core checklist, each specialist, the Red Team, the outside voice) carries this definition: CRITICAL means the floor above; everything else is INFORMATIONAL. Data loss, a trust-boundary bypass and uncapped spend stay forced CRITICAL (the sideways sweep rule); no lane, specialist, dedup or saved decision downgrades them.

NO FINDINGS is a result

A reviewer that finds nothing answers NO FINDINGS and nothing else. That is a completed, clean result, never a failed review and never a reason to invent an item to show work. Missing or unusable reviewer output is the opposite: incomplete coverage, which blocks until the reviewer is rerun.

How /ship converges (review_scope: frozen, the default)

1. Pass 1 reviews the whole diff against the merge base. Every finding goes through gstack-review-scope classify, which stamps it with locus (diff: a hunk the PR changed, with three lines of context; outside: anything else), kind, blocking and scope. Findings in the diff are fix. A blocking finding in code the PR did not change is defer: gstack-review-scope defer files it as a GitHub issue (one per finding, reused across reruns through an <!-- gstack-deferred-finding: <fingerprint> --> marker; the issue text is scanned like the PR body before anything is posted, so a finding that quotes a secret is unfiled (publication scan refused: …); unfiled (<reason>) when gh is unavailable or its search fails; every unfiled case still exits 0) and the PR body lists it under ## Deferred findings. A finding's cause (the changed line behind a defect reported elsewhere, a deleted file included) places it in the diff. Below-floor findings outside the diff are note, listed under ## Review notes.
2. Pass 2 and later review only the range since the previous pass. Each pass saves its head; the next pass diffs RANGE_BASE..HEAD for every reviewer (the gate scan and QA probes keep the whole candidate) and classifies with --range-base. Only a blocking finding in that range or in the diff is fix; every below-floor finding is a note. A finding the diff causes in code it did not change names the changed line in cause, and the locus follows it.
3. Three passes is the cap. A pass that applies no edits is the exit: the PR ships with its deferred and noted items named in the body. A blocking finding still in fix scope on pass 3 stops the run and names the finding (path, severity, problem) for the owner; a fourth pass is the owner's call, never the loop's.

The same floor and the same NO FINDINGS rule apply to /review on its own; its re-review loop keeps its three-cycle fix cap (CYCLES), and a pass that applies no edits is its exit too.

What the receipt records

gstack-review-scope summary --since <REVIEW_SINCE> reads this invocation's review-log rows and writes the counters gstack-ship-receipt write --review-loop puts in the receipt:

Field	Meaning
review_loop.passes	review passes this ship ran (1 to 3)
review_loop.blocking_found	distinct blocking findings across the passes
review_loop.deferred	blocking findings in unchanged code filed as issues (a Step 11 late defer, logged as a review-late-defer row so it never displaces the newest review pass, counts here and is not a pass)
review_loop.noted	below-floor findings listed in the PR body
review_loop.fixed	findings fixed in this PR
review_loop.scope	the review_scope the loop ran under

The receipt's summary line prints passes=<n> blocking_found=<k> deferred=<m>, which is what a scorecard tracks (target: a median of 2 passes per PR). A receipt carried across a base merge or a test-only fix (ship-policy.md#receipt-carry) keeps these counters, because the reviewed product diff is unchanged.

The scope knob

.gstack/ship-policy.json review_scope (ship-policy.md#review-scope):

Value	Pass 1	Blocking finding in unchanged code	Pass 2+	Cap
frozen (default)	the diff	filed as an issue, listed as deferred	the range since the previous pass, blocking only	3 passes
diff-plus-blocking	the diff	fixed in this PR	the range since the previous pass, blocking only	3 passes
all	everything	fixed in this PR	the whole diff, every finding	3 fix cycles

diff-plus-blocking is the fallback for a repository where deferred issues pile up; all is the loop as it ran before the key existed. A value other than frozen needs min_gstack_version at or past the release that added the key (REVIEW_SCOPE_KEY_VERSION in lib/ship-policy.ts) so an older gstack refuses the file by name instead of ignoring the key.

Reviewer fan-out

The review army launches every selected specialist in one message so they run in parallel; a host that caps running subagents makes that impossible past the cap. In /ship the knob is a prompt flag, --review-fanout auto|serial|parallel (default auto), read where the force flags (--all-specialists) are (/review on its own keeps the single parallel batch: its generated SKILL.md sits at its size pin, and a refused launch there is a failed reader, never dropped coverage):

Value	Batches
auto	when the host reports fewer free subagent slots than selected specialists, batches of the free-slot count (at least one), each launched in one message, the next only after every reader of the previous one finished or is confirmed stopped; a host that reports no slot count runs one parallel batch
serial	batches of one
parallel	one batch regardless of slots; a refused launch is a failed reader, never silently dropped coverage

Capy caps a thread at 8 running subagents, and waiting or idle ones hold a slot, so under auto a nine-specialist review on an otherwise idle Capy thread runs as one batch of 8 and one of 1 (Fan-out: 9 specialists in 2 batches of 8). Batching changes the order, never the set: every selected specialist runs before the merge stage, and the Red Team's activation reads the merged result as before.

Two checklist rules with ids

Two findings review/checklist.md names by rule id so a PR body, a review log and a later reader agree on what was flagged:

• prereg-with-results (Pass 1, Gate Integrity, ASK): one diff adds or changes an eval's preregistration (bars, arms, decoys, stop rules, a plan file) and also adds that eval's results, scores or verdict. The bar could have been set after the outcome, so the pairing is the finding. The repair is a split: the preregistration lands first and the results PR cites its merged commit.
• test-keyboard-count-loop (Pass 2, informational): a browser-driver test reaches an element by a counted loop of key presses and asserts on whatever has focus, so the count encodes today's DOM order. Locate the target by role, label or test id; a counted loop stays only when the count is the behavior under test.

Porting a contributor's work

A ported branch keeps the contributor's commits as theirs and adds the porter's fixes on top, each crediting the original authors. gstack-coauthor-trailers [<range> | --base <ref>] [--message <file>] [--exclude <email>]... lists every distinct author of the range's commits (default origin/<base>..HEAD) other than the checkout's own committer identity, in first-appearance order, as Co-authored-by: Name <email> lines; --message <file> adds the ones the commit message file lacks to its trailer block (git interpret-trailers, pinned placement, so an existing co-author keeps attribution), matched by email case-folded, so running it twice changes nothing. The COAUTHORS: <n> in <range> line on stderr is the receipt; --json prints { range, authors, trailers, appended }.

Where this is enforced

• scripts/resolvers/review-army.ts: the floor and NO FINDINGS in every specialist and Red Team prompt (rendered into review/sections/review-army.md and ship/sections/review-army.md); in /ship every specialist and Red Team prompt it renders carries its diff base as a literal sha the parent writes in (DIFF_BASE=<diff-base>: the merge base on pass 1, RANGE_BASE from pass 2 on), because a reviewer is its own process and never sees the parent's shell variables; the fan-out batches above.
• ship/sections/review-army.md Step 9: passes, RANGE_BASE, classify, defer, render, the cap check before any edit, the Step 11 late-defer row, scratch files under .gstack/tmp/, the cap decisions; ship/sections/adversarial.md Step 11: the outside voice reads the same range and scopes queued fixes the same way.
• lib/review-scope.ts, bin/gstack-review-scope: classify, defer, render, summary; refusals are REVIEW_SCOPE_INPUT and REVIEW_SCOPE_RANGE (troubleshooting.md).
• lib/ship-policy.ts: the review_scope key and its ship: review_scope … consequence line.
• review/checklist.md: prereg-with-results under Gate Integrity and test-keyboard-count-loop under Pass 2; bin/gstack-coauthor-trailers for the contributor-credit trailers of a port.
• lib/ship-receipt-prose.ts, gstack-ship-receipt read --check-prose: the body's quoted counters against the receipt (RECEIPT_PROSE_MISMATCH, ship-policy.md).
• lib/ship-receipt.ts, lib/headless-artifacts.ts: the review_loop receipt object, its schema and the summary line.