docs(748): drop the attempt tally and the duplicated clause

Two tidy-ups from the final review, both in the withdrawal note added last
commit.

"three successive attempts at one were each false in a different way" is
autobiography — it only parses for someone who watched the review
(`docs.no-session-narrative`). The durable content is the MECHANISM, which the
same sentence already gives: any such summary generalizes from the injected
token, which `permissions:` scopes, to every credential a job can reach, which
it does not touch. The count is in the commit messages, where it belongs.

The note's closing clause restated "a collaborator's own token is a route with
no workflow at all" immediately before the pre-existing sentence saying exactly
that. Dropped, and "the precise facts are each stated on their own below" went
with it — inaccurate once the SHAPE fact had been moved INTO the note.

Kept deliberately: the note itself, and the concrete falsifying case
(`RENOVATE_TOKEN` is referenced by `renovate.yml`, one of the five holding
`code: read`). That is "what was rejected and why, so it is not re-adopted",
which the doc rule protects — and the counterexample is a fact none of the three
summary versions contained.

Decisions-Edit: yes
Refs: #748

docs/decisions/README.md

@@ -49,7 +49,7 @@ the link for rationale. Superseded/retired history lives in `archive/`. Regenera
 | `ci.exemption-provenance` | The three inputs the exemption decision rests on must each be bound to something the judged PR cannot mutate. (1) BASE — `scripts/pr-changed-files.sh` takes the expected base BRANCH as a REQUIRED 5th argument and re-reads it before and after paging, because `/pulls/{n}/files` diffs against the PR's live base and retargeting moves the answer without moving the head sha; the workflow passes `github.event.pull_request.base.ref` from the `pull_request_target` payload, which a retarget cannot rewrite. (2) BOT EXEMPTION — an author match is necessary but never sufficient: `pull_request.user.login` is the PR's immutable CREATOR while its head is not, so the exemption additionally requires EVERY changed path to be a dependency manifest (`Directory.Packages.props` or `.config/dotnet-tools.json`, and ONLY those — the npm manifests are excluded because `package.json` `scripts` are executed by CI). (3) INHERITED SUCCESS — the never-overwrite short-circuit fires for a `success` only when it is POSITIVELY identified as an APPROVED REVIEWER's verdict for THIS base, meaning a `.creator.login` that is a member of the workflow's `H10_REVIEWERS` allow-list (an existing `failure` takes the weaker ATTRIBUTABLE test and needs no membership, because inheriting a rejection can only withhold an exemption while re-deriving one can turn it green on an exempt PR) — non-null was too weak, since any account's credential satisfies it and `RENOVATE_TOKEN` is one that cannot be scoped down (#742) — AND a `Review-verdict:` description AND, when that description records a base (`(base: …)`, `release.verdict-status-check`), a base matching the PR's — tested by requiring the description to END with the exact literal `(base: <base>)` and to contain exactly ONE such marker, never by extracting a value (see below); a present-but-different base is rejected, an absent one is not, since verdicts predating that convention carry none; every other shape, including any unrecognised one, is re-derived rather than trusted. The bot and docs-only exemptions are evaluated as INDEPENDENT predicates and the decision made afterwards, never as an `elif` chain. `edited` is in the workflow's `types:` so a retarget reclassifies — which gives DETECTION, not atomicity: status writes are not serialized, so a stale run can still post over a fresher one. That residual is now FENCED rather than merely tracked (NARROWED, not resolved — a retarget between the fence's final count and the POST still leaves a PERMANENT forged green, #849) — the job refuses to write at all if the PR's timeline retarget COUNT moved while it was classifying (`ci.verdict-write-retarget-fence`, #706) — leaving TWO windows, not one: the sub-round-trip window that no API without compare-and-set can close, AND the post-final-count/pre-POST window, which is not sub-round-trip and yields a PERMANENT green because the successor can consume the `edited` event and exit before the stale run posts last (#849). The PROTECTED path list additionally covers `CLAUDE.md` and `AGENTS.md` (#751) — they are not prose but the documents DEFINING the completion protocol, the merge-consent convention and the H10 rule, so protecting `.claude/` while the file specifying what it enforces stayed docs-only-exempt was the same self-exemption one directory over; driving the real classify body with a lone `CLAUDE.md` change produced an exemption `success`. `README.md` is deliberately not listed. It also covers `.codex/` (#711), which mirrors `.claude/hooks/` byte for byte including the merge-consent hook — latent while that directory is untracked, live the moment it is tracked; the list stays ENUMERATIVE rather than derived, because a derived rule would have to be evaluated against the very file list being classified. Reading the CURRENT status for input (3) must tolerate `statuses: null`: `GET /commits/{sha}/status` serialises a nil slice as `null`, not `[]`, on a head with no statuses yet, and an `array`-only gate made `read_existing_verdict` `exit 1` and post nothing at all (#751, `ci.workflow-run-body-no-expressions`) — `null` is accepted only when `total_count` is 0, so a body that merely lost its array is still refused. Path predicates are evaluated by COUNTING with `grep -c`, never `\| grep -q` (SIGPIPE inversion) and never a here-string (temp-space failure) — see `ci.grep-q-pipefail-inversion`. | 2026-07-29 | [link](records/ci/exemption-provenance.md) |
 | `ci.format-gate-folder-mode` | The blocking `format` CI job (and matching pre-commit hook) runs `dotnet format whitespace . --folder --include <files>` instead of loading the full MSBuild/Roslyn solution, cutting the gate from ~480s to ~0.5s with unchanged whitespace/charset coverage. | 2026-07-19 | [link](records/ci/format-gate-folder-mode.md) |
 | `ci.functional-e2e-harness` | The `functional-e2e` CI job boots the PR's own code from source via `dotnet run` (`scripts/e2e-local.sh`) and runs deterministic assertions (`scripts/e2e-functional.sh`) as an advisory (non-blocking) job, not a `build` dependency or required check. Originally curl-only; since #445 the same job carries a second, headless-browser step for the contracts curl cannot express — see `ci.ui-e2e-harness`. | 2026-07-16 | [link](records/ci/functional-e2e-harness.md) |
-| `ci.gate-trigger-base-resolved` | The workflow that writes the branch-protection-required `review-verdict/h10` status triggers on `pull_request_target` with `branches: [main]`, never on plain `pull_request`. Gitea resolves a `pull_request` workflow DEFINITION from the PR's own head commit, so under that trigger a PR editing `.gitea/workflows/review-verdict.yml` ran its own rewritten copy and could post `h10=success` for itself; `pull_request_target` resolves the definition from the base instead. The `branches: [main]` filter is part of the rule, not a refinement of it: base resolution only relocates the rewrite from the head to the base, so without the filter a PR opened into an attacker-pushed base branch runs that branch's gate. `pull_request_target` is safe HERE only because this job never checks out or executes head-supplied code — it checks out `base.sha` and runs only that tree's scripts (`ci.shared-pr-file-enumeration`); reintroducing a head checkout under this trigger would be worse than the bug it fixed. This closes the rewrite route through THIS workflow and does NOT close the class. Gitea injects `GITEA_TOKEN` into EVERY job and it USED to be write-capable everywhere, so any ref-resolved workflow could forge `review-verdict/h10`; since #748 (2026-08-27) all six workflows here declare `permissions:` — five `code: read`, and `review-verdict.yml`'s gate job `code: write`, deliberately, because it IS the gate (the five rest on the TOP-LEVEL form, which is INFERRED rather than probed — the gate job's JOB-LEVEL form is the one measured; see `ci.actions-credential-scoping`). That narrows the INJECTED token and only that: deliberately NO "only X can post a status" summary is stated, because three attempts at one were each false in a different way, every time by generalizing from the injected token to every credential a job can reach — `RENOVATE_TOKEN` is in the same secret store and is referenced by `renovate.yml`, one of the five. `ci-image.yml` was the last holdout — its unfiltered `push:` made it the worst-placed of the six — and #744 closed that trigger route (`ci.toolchain-image-publish-is-a-dispatch`) while #748 scoped its token. So the route is NARROWED, not closed, and the SHAPE is open — a newly added workflow declaring write, or omitting a declaration and inheriting the owner default, is a route again, which is why `test_pr_changed_files.py` asserts every tracked workflow declares a block. And a collaborator's own API token still can, since branch protection binds the context and not its issuer. The credential half is now RESOLVED in `ci.actions-credential-scoping` (#697): CI's registry secret was the ADMIN account's basic auth and is now a PAT that cannot post a status, which removes the ADMIN escalation and that credential's route (an ALLOW-LISTED user credential's forgery carries a matching `creator` and is inherited as a verdict; an Actions job's carries `creator: null` and is re-derived, as since #742 is every account outside `H10_REVIEWERS` — but do NOT read that asymmetry as protection: re-derivation fires only on the trigger's `types`, and posting a status is not one of them, so a POST timed after the last PR event simply stands). It does not remove EVERY route: `RENOVATE_TOKEN` is a `write:repository` bot PAT in the same secret store, reachable by any PR-added workflow. The owner-level Restricted default (server-management#714) remains a separate OPEN lever — its effect on a declared `code: write` is unmeasured, and the version half of that condition has been satisfied since the 1.25.4 -> 1.27.1 upgrade on 2026-08-05, so it is not something to wait on a Gitea release for. A collaborator's own token remains unfixable; the exemption path has its own separate defects in #698. | 2026-07-28 | [link](records/ci/gate-trigger-base-resolved.md) |
+| `ci.gate-trigger-base-resolved` | The workflow that writes the branch-protection-required `review-verdict/h10` status triggers on `pull_request_target` with `branches: [main]`, never on plain `pull_request`. Gitea resolves a `pull_request` workflow DEFINITION from the PR's own head commit, so under that trigger a PR editing `.gitea/workflows/review-verdict.yml` ran its own rewritten copy and could post `h10=success` for itself; `pull_request_target` resolves the definition from the base instead. The `branches: [main]` filter is part of the rule, not a refinement of it: base resolution only relocates the rewrite from the head to the base, so without the filter a PR opened into an attacker-pushed base branch runs that branch's gate. `pull_request_target` is safe HERE only because this job never checks out or executes head-supplied code — it checks out `base.sha` and runs only that tree's scripts (`ci.shared-pr-file-enumeration`); reintroducing a head checkout under this trigger would be worse than the bug it fixed. This closes the rewrite route through THIS workflow and does NOT close the class. Gitea injects `GITEA_TOKEN` into EVERY job and it USED to be write-capable everywhere, so any ref-resolved workflow could forge `review-verdict/h10`; since #748 (2026-08-27) all six workflows here declare `permissions:` — five `code: read`, and `review-verdict.yml`'s gate job `code: write`, deliberately, because it IS the gate (the five rest on the TOP-LEVEL form, which is INFERRED rather than probed — the gate job's JOB-LEVEL form is the one measured; see `ci.actions-credential-scoping`). That narrows the INJECTED token and only that: deliberately NO "only X can post a status" summary is stated here, because any such summary generalizes from the injected token, which `permissions:` scopes, to every credential a job can reach, which it does not touch — `RENOVATE_TOKEN` is in the same secret store and is referenced by `renovate.yml`, one of the five holding `code: read`. `ci-image.yml` was the last holdout — its unfiltered `push:` made it the worst-placed of the six — and #744 closed that trigger route (`ci.toolchain-image-publish-is-a-dispatch`) while #748 scoped its token. So the route is NARROWED, not closed, and the SHAPE is open — a newly added workflow declaring write, or omitting a declaration and inheriting the owner default, is a route again, which is why `test_pr_changed_files.py` asserts every tracked workflow declares a block. And a collaborator's own API token still can, since branch protection binds the context and not its issuer. The credential half is now RESOLVED in `ci.actions-credential-scoping` (#697): CI's registry secret was the ADMIN account's basic auth and is now a PAT that cannot post a status, which removes the ADMIN escalation and that credential's route (an ALLOW-LISTED user credential's forgery carries a matching `creator` and is inherited as a verdict; an Actions job's carries `creator: null` and is re-derived, as since #742 is every account outside `H10_REVIEWERS` — but do NOT read that asymmetry as protection: re-derivation fires only on the trigger's `types`, and posting a status is not one of them, so a POST timed after the last PR event simply stands). It does not remove EVERY route: `RENOVATE_TOKEN` is a `write:repository` bot PAT in the same secret store, reachable by any PR-added workflow. The owner-level Restricted default (server-management#714) remains a separate OPEN lever — its effect on a declared `code: write` is unmeasured, and the version half of that condition has been satisfied since the 1.25.4 -> 1.27.1 upgrade on 2026-08-05, so it is not something to wait on a Gitea release for. A collaborator's own token remains unfixable; the exemption path has its own separate defects in #698. | 2026-07-28 | [link](records/ci/gate-trigger-base-resolved.md) |
 | `ci.gitea-milestone-filter-noop` | Never filter issues with the server-side `?milestones=<name>` parameter — fetch all open issues once and filter LOCALLY on each issue's `.milestone.title`. | 2026-07-21 | [link](records/ci/gitea-milestone-filter-noop.md) |
 | `ci.grep-q-pipefail-inversion` | In any script running under `set -o pipefail`, a security or classification predicate of the form `producer \| grep -q…` is FORBIDDEN: `grep -q` exits at its first match, the producer then takes SIGPIPE and exits 141 once the data exceeds the pipe buffer (~64K), so `pipefail` reports the pipeline as FAILED even though grep MATCHED — inverting the predicate exactly when the input is large. A here-string (`grep -q… <<< "$data"`) is ALSO forbidden: bash materialises a large here-string via temporary storage, so it fails when temp space is full or unwritable, and inside an `if`/`!` that failure flips the predicate the same way. COUNT instead — `n=$(printf '%s\n' "$data" \| grep -cE "$re")` — because `grep -c` drains stdin (no early exit, no SIGPIPE) over an ordinary pipe (no temp file). Read grep's status honestly: exit 1 means a zero count and is a legitimate answer, anything >1 is a real error. Evaluate the counts ONCE at TOP LEVEL, never inline inside an `if`/`elif` condition: inside `$( )` an `exit` leaves only the subshell and `set -e` does not fire, so an error silently reads as "no match". Validate that each result is numeric and fail closed if not. This applies to both the enforced gate `.gitea/workflows/review-verdict.yml` and the advisory hook `.claude/hooks/pretooluse-merge-consent.sh`. | 2026-07-29 | [link](records/ci/grep-q-pipefail-inversion.md) |
 | `ci.infra-shaped-red-under-load` | When a job dies inside a setup/cache step before your code compiles, check the runner host's load before diagnosing the diff, and never file a CI bug off one sample under pressure. | 2026-07-21 | [link](records/ci/infra-shaped-red-under-load.md) |

docs/decisions/records/ci/gate-trigger-base-resolved.md

@@ -5,7 +5,7 @@ status: active
 since: '2026-07-28'
 supersedes: none
 superseded-by: none
-rule: 'The workflow that writes the branch-protection-required `review-verdict/h10` status triggers on `pull_request_target` with `branches: [main]`, never on plain `pull_request`. Gitea resolves a `pull_request` workflow DEFINITION from the PR''s own head commit, so under that trigger a PR editing `.gitea/workflows/review-verdict.yml` ran its own rewritten copy and could post `h10=success` for itself; `pull_request_target` resolves the definition from the base instead. The `branches: [main]` filter is part of the rule, not a refinement of it: base resolution only relocates the rewrite from the head to the base, so without the filter a PR opened into an attacker-pushed base branch runs that branch''s gate. `pull_request_target` is safe HERE only because this job never checks out or executes head-supplied code — it checks out `base.sha` and runs only that tree''s scripts (`ci.shared-pr-file-enumeration`); reintroducing a head checkout under this trigger would be worse than the bug it fixed. This closes the rewrite route through THIS workflow and does NOT close the class. Gitea injects `GITEA_TOKEN` into EVERY job and it USED to be write-capable everywhere, so any ref-resolved workflow could forge `review-verdict/h10`; since #748 (2026-08-27) all six workflows here declare `permissions:` — five `code: read`, and `review-verdict.yml`''s gate job `code: write`, deliberately, because it IS the gate (the five rest on the TOP-LEVEL form, which is INFERRED rather than probed — the gate job''s JOB-LEVEL form is the one measured; see `ci.actions-credential-scoping`). That narrows the INJECTED token and only that: deliberately NO "only X can post a status" summary is stated, because three attempts at one were each false in a different way, every time by generalizing from the injected token to every credential a job can reach — `RENOVATE_TOKEN` is in the same secret store and is referenced by `renovate.yml`, one of the five. `ci-image.yml` was the last holdout — its unfiltered `push:` made it the worst-placed of the six — and #744 closed that trigger route (`ci.toolchain-image-publish-is-a-dispatch`) while #748 scoped its token. So the route is NARROWED, not closed, and the SHAPE is open — a newly added workflow declaring write, or omitting a declaration and inheriting the owner default, is a route again, which is why `test_pr_changed_files.py` asserts every tracked workflow declares a block. And a collaborator''s own API token still can, since branch protection binds the context and not its issuer. The credential half is now RESOLVED in `ci.actions-credential-scoping` (#697): CI''s registry secret was the ADMIN account''s basic auth and is now a PAT that cannot post a status, which removes the ADMIN escalation and that credential''s route (an ALLOW-LISTED user credential''s forgery carries a matching `creator` and is inherited as a verdict; an Actions job''s carries `creator: null` and is re-derived, as since #742 is every account outside `H10_REVIEWERS` — but do NOT read that asymmetry as protection: re-derivation fires only on the trigger''s `types`, and posting a status is not one of them, so a POST timed after the last PR event simply stands). It does not remove EVERY route: `RENOVATE_TOKEN` is a `write:repository` bot PAT in the same secret store, reachable by any PR-added workflow. The owner-level Restricted default (server-management#714) remains a separate OPEN lever — its effect on a declared `code: write` is unmeasured, and the version half of that condition has been satisfied since the 1.25.4 -> 1.27.1 upgrade on 2026-08-05, so it is not something to wait on a Gitea release for. A collaborator''s own token remains unfixable; the exemption path has its own separate defects in #698.'
+rule: 'The workflow that writes the branch-protection-required `review-verdict/h10` status triggers on `pull_request_target` with `branches: [main]`, never on plain `pull_request`. Gitea resolves a `pull_request` workflow DEFINITION from the PR''s own head commit, so under that trigger a PR editing `.gitea/workflows/review-verdict.yml` ran its own rewritten copy and could post `h10=success` for itself; `pull_request_target` resolves the definition from the base instead. The `branches: [main]` filter is part of the rule, not a refinement of it: base resolution only relocates the rewrite from the head to the base, so without the filter a PR opened into an attacker-pushed base branch runs that branch''s gate. `pull_request_target` is safe HERE only because this job never checks out or executes head-supplied code — it checks out `base.sha` and runs only that tree''s scripts (`ci.shared-pr-file-enumeration`); reintroducing a head checkout under this trigger would be worse than the bug it fixed. This closes the rewrite route through THIS workflow and does NOT close the class. Gitea injects `GITEA_TOKEN` into EVERY job and it USED to be write-capable everywhere, so any ref-resolved workflow could forge `review-verdict/h10`; since #748 (2026-08-27) all six workflows here declare `permissions:` — five `code: read`, and `review-verdict.yml`''s gate job `code: write`, deliberately, because it IS the gate (the five rest on the TOP-LEVEL form, which is INFERRED rather than probed — the gate job''s JOB-LEVEL form is the one measured; see `ci.actions-credential-scoping`). That narrows the INJECTED token and only that: deliberately NO "only X can post a status" summary is stated here, because any such summary generalizes from the injected token, which `permissions:` scopes, to every credential a job can reach, which it does not touch — `RENOVATE_TOKEN` is in the same secret store and is referenced by `renovate.yml`, one of the five holding `code: read`. `ci-image.yml` was the last holdout — its unfiltered `push:` made it the worst-placed of the six — and #744 closed that trigger route (`ci.toolchain-image-publish-is-a-dispatch`) while #748 scoped its token. So the route is NARROWED, not closed, and the SHAPE is open — a newly added workflow declaring write, or omitting a declaration and inheriting the owner default, is a route again, which is why `test_pr_changed_files.py` asserts every tracked workflow declares a block. And a collaborator''s own API token still can, since branch protection binds the context and not its issuer. The credential half is now RESOLVED in `ci.actions-credential-scoping` (#697): CI''s registry secret was the ADMIN account''s basic auth and is now a PAT that cannot post a status, which removes the ADMIN escalation and that credential''s route (an ALLOW-LISTED user credential''s forgery carries a matching `creator` and is inherited as a verdict; an Actions job''s carries `creator: null` and is re-derived, as since #742 is every account outside `H10_REVIEWERS` — but do NOT read that asymmetry as protection: re-derivation fires only on the trigger''s `types`, and posting a status is not one of them, so a POST timed after the last PR event simply stands). It does not remove EVERY route: `RENOVATE_TOKEN` is a `write:repository` bot PAT in the same secret store, reachable by any PR-added workflow. The owner-level Restricted default (server-management#714) remains a separate OPEN lever — its effect on a declared `code: write` is unmeasured, and the version half of that condition has been satisfied since the 1.25.4 -> 1.27.1 upgrade on 2026-08-05, so it is not something to wait on a Gitea release for. A collaborator''s own token remains unfixable; the exemption path has its own separate defects in #698.'
 signals: 'workflow definition resolved from head, PR rewrites the gate that judges it, self-approve a required status check, pull_request_target vs pull_request, gate trigger branches filter, attacker-supplied base branch, how to test a change to review-verdict.yml, workflow not exercised by its own PR, gate edit goes live only on merge, required_approvals 0 does not bind an author, forged commit status inherited by sha · paths: `.gitea/workflows/review-verdict.yml`, `scripts/tests/test_pr_changed_files.py` · issues: #672, #663, #649, #622'
 mechanics: '`on: pull_request_target: {branches: [main], types: [opened, reopened, synchronize, ready_for_review, edited]}` (`edited` added by `ci.exemption-provenance` so a retarget reclassifies); asserted by `test_the_workflow_trigger_is_pull_request_TARGET_scoped_to_main` in `scripts/tests/test_pr_changed_files.py`; the job''s own context is renamed to `... (pull_request_target)` and must stay OUT of branch protection''s required list'
 ---
@@ -61,13 +61,12 @@ holdout: its unfiltered `push:` trigger made it the worst-placed of the six, and
 route (`ci.toolchain-image-publish-is-a-dispatch`) in the same week #748 scoped its token.
 
 **What that narrows is the INJECTED token, and only that.** No one-line "only X can post a status"
-summary belongs here — three successive attempts at one were each false in a different way, because
-every one of them quietly generalized from the injected token to every credential a job can reach.
-The precise facts are each stated on their own below and none of them needs a summary: the SHAPE is
-open (a new workflow that declares write, or omits a declaration and inherits the owner default, is a
-route again, which is why `test_pr_changed_files.py` asserts every tracked workflow declares a
-block); `RENOVATE_TOKEN` still writes statuses and is referenced by `renovate.yml`, one of the five;
-and a collaborator's own token is a route with no workflow at all. A collaborator's own API token is a
+summary belongs here: every such summary quietly generalizes from the injected token, which
+`permissions:` scopes, to every credential a job can reach, which it does not touch. The falsifying
+case is concrete and current — `RENOVATE_TOKEN` still writes statuses and is referenced by
+`renovate.yml`, one of the five holding `code: read`. The SHAPE is open too: a new workflow that
+declares write, or omits a declaration and inherits the owner default, is a route again, which is why
+`test_pr_changed_files.py` asserts every tracked workflow declares a block. A collaborator's own API token is a
 route with no workflow at all — branch protection binds the *context*, not its issuer. Full inventory
 in `#697`, whose credential half is resolved in `ci.actions-credential-scoping` — the registry secret
 no longer carries status-write. That does NOT leave the workflow routes provenance-free: any