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+# Slice 1 S2b: gated approvals are single-use (2026-10-05)
+
+Status: written by Sage, lead, under lead decision 63. It follows
+`docs/plans/BRIEF-TEMPLATE.md`, and it amends no section of the slice 1
+brief.
+
+## S2b: gated approvals are single-use (authorize records consumption)
+
+### Problem
+
+In S2 round 2 (`agents/rocko/work/slice1-s2-r2/`, candidate manifest
+61519059…), `broker.authorize(cap, action, {decision, target})` checks
+that the decision is resolved and approved, then appends an
+`action.allowed` event. Nothing stops a second call with the same
+decision. Darkwing's probe P3 (`agents/darkwing/work/slice1-s2-review/`)
+deploys three times on one approval. A gated decision is Jason saying yes
+to one action, so one approval must authorize one action.
+
+### Owner and reviewer
+
+- Owner: rocko.
+- Reviewer: darkwing.
+
+### Files owned
+
+- `packages/bus/src/broker.mjs` and `packages/bus/src/store.mjs`, for the
+  check.
+- `packages/bus/tests/broker.test.mjs` and, if a new test file is
+  cleaner, one new file under `packages/bus/tests/`.
+- `packages/bus/README.md`, the paragraph on `authorize`.
+
+### What ships
+
+- For a gated decision, `authorize` refuses with `decision-consumed` if
+  an `action.allowed` event already names that decision. The check and
+  the new event run in the same transaction, so two concurrent calls
+  can't both pass.
+- Routine, within-role and cross-role decisions keep their current
+  behavior unless Darkwing's review shows the same hole matters there.
+  If it does, the review names it and I rule on it.
+- No schema change is expected, because the `action.allowed` event
+  already carries the decision. If one is needed, Darkwing writes it as
+  schema v3c and S2b pins it.
+- Tests: the second use refuses, a use in another run refuses, a use
+  after the broker restarts refuses, and a fresh approval of the same
+  action works. Add a mutant that drops the check.
+- Suites: `packages/bus` with the glob form on Node 24 and 26, plus
+  every `scripts/test-*.sh`.
+
+### Out of scope
+
+- Who calls `authorize` and when. That's S3's tasks and S6's launches.
+- Expiring an approval that is never used.
+
+### Gate
+
+Darkwing approves on the row's issue. Sage runs the integration gate
+(every suite, live-provider cases included) on an index export before
+committing. This has to land before S3 or S6 calls `authorize` for a
+gated action.