Issue 313: history adopted at the switch was held for a person; ADR 0250 retires it and ends owed work the forge cannot do

02-DECISIONS/0250-a-merge-heard-only-from-the-buss-history-is-retired-and-owed-work-the-forge-cannot-do-ends.md

@@ -0,0 +1,96 @@
+---
+topic: the mesh
+status: accepted
+date: 2026-10-08
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0239-a-delivery-is-owned-by-the-mesh-delivery-module-and-runs-from-commit-to-delivered.md
+---
+
+# 250. A merge heard only from the bus's history is retired, and owed work the forge cannot do ends
+
+## Context
+
+[ADR 0239](0239-a-delivery-is-owned-by-the-mesh-delivery-module-and-runs-from-commit-to-delivered.md)
+gives the delivery's owner one table of states. Decision 10, *the switch*, adopts the walks open when the
+owner is first assigned. It does not mention the merges the bus still holds from before. A new consumer of the
+forge's `pull.merged` hears them all again. The owner took each as a fresh merge whose head it had never
+heard, and its row *merged unchecked → held* held each one for a person.
+
+At the first switch that was 688 deliveries, merged from four days to two hours earlier, all on the machines
+long before
+([issue 313](../04-ISSUES/313-history-was-held-for-a-person-and-its-views-retried-for-ever/00-report.md)).
+`held` could be left only by a release, which walks, or a stop, which says a person stopped a running
+delivery. Neither is true of history. The self-check listed every one past its bound.
+
+Decision 5 says owed work is "retried until done". A view on a pull request the forge no longer holds can
+never be done. It was tried every ten seconds, 11,000 times each, and nothing said so.
+
+## Considered Options
+
+1. **A final state `retired` for history, taken at adoption, and a person's act for what is already held.**
+   Chosen.
+2. **Adopt history as `delivered`.** It did reach the machines, but this owner did not deliver it, and
+   `delivered` is the word for a walk this owner saw done. Rejected.
+3. **Stop them.** `stopped` means a person ended a delivery, and its status is an error on the commit.
+   Rejected.
+4. **Let healer H2's `close` take held history.** `held` is the operator's by design. A healer leaving it
+   unasked would hide the case where the rule is wrong. Rejected for the deliveries already held. New history
+   is not held at all, so no healer is needed for it.
+5. **Skip merges from the bus's history altogether.** Then the commit's note would keep no record that this
+   owner heard them, and a merge heard late for another reason would go unrecorded. Rejected.
+
+## Decision
+
+1. **History is a delivery made from the forge's word at its merge, heard fifteen minutes or more after
+   that merge, and with no walk of it open.** The forge says a merge within seconds, so one heard that late was
+   replayed. A walk the controller keeps open or waiting for it makes it a delivery, never history.
+2. **A new final state, `retired`.** It is reached in two ways:
+   - *history*, an observed row from `proposed`, `checked`, `ready` and `rejected`, taken before any other.
+     New history goes there at adoption and is never checked, held or walked;
+   - *retire*, a person's act from `held`, with why, whose guard is the rule of point 1. It is never a release:
+     nothing is walked, delivered or put back.
+3. **The seat gains `retire-history`.** It takes one delivery by id and is refused when the rule does not
+   take it. Or it takes every held delivery, of one repository when named, and answers how many it retired and
+   which it left held and why. `dry` answers the same and changes nothing. The verb is promised by the
+   controller as optional before the holder serves it
+   ([ADR 0246](0246-a-seats-new-verb-is-promised-before-it-is-required.md)).
+4. **History is not shown on its pull request.** Its transitions are said on the bus and kept on the commit's
+   note. No view or `mesh/delivery` status is asked: the forge may no longer hold that pull request, or may
+   hold another under its number.
+5. **Owed work ends.** This replaces "retried until done" in decision 5:
+   - the forge's own answer that what an effect is for does not exist (a 404, or "does not exist") is final.
+     The effect is given up with one line among the owner's refusals;
+   - any other failure is tried again later each time: ten seconds, doubling to an hour. After sixty tries,
+     about two days, it is given up the same way.
+
+## Consequences
+
+- The deliveries held at the first switch are retired by one call of `retire-history`, after a dry run says
+  how many. The self-check's findings for them end.
+- A switch, a reassignment or a lost consumer position no longer turns the bus's history into work for a
+  person.
+- A merge heard late that is not history, because its walk waits, is held as before.
+- An owed effect can now be lost. When it is, the owner says so, and the commit's note keeps whatever was
+  already written.
+
+**How it is checked.** mesh-delivery's tests: `TestAMergeLongPastHeardFromTheForgesWordIsRetiredAtAdoption`
+(history retired at adoption, with nothing asked of its pull request; a live merge from the forge's word and
+a merge whose walk is open are not history; a reused number does not merge an old delivery again),
+`TestRetireHistoryRetiresTheAdoptedHistoryInBulkAndLeavesEveryOtherHeldOne` (dry first, then the bulk retire;
+nothing asked of the controller; a retired delivery cannot be released),
+`TestRetireHistoryIsRefusedForARealHeldDelivery`, and `TestOwedWorkTheForgeSaysCanNeverBeDoneIsDropped` (a
+final answer is given up after one try and said; other failures back off and end). The table's own tests
+take and refuse both new rows. The controller's `TestTheDeliverySeatPromisesRetireHistoryOptionally` checks
+the seat promises the verb as optional.
+
+## References
+
+- [Issue 313](../04-ISSUES/313-history-was-held-for-a-person-and-its-views-retried-for-ever/00-report.md),
+  its report and diagnosis.
+- [ADR 0239](0239-a-delivery-is-owned-by-the-mesh-delivery-module-and-runs-from-commit-to-delivered.md),
+  decisions 2, 5 and 10.
+- [ADR 0246](0246-a-seats-new-verb-is-promised-before-it-is-required.md), a verb promised before it is
+  required.
+- [Design 47](../03-DESIGN/01-to-be/47-delivery-from-commit-to-delivered.md), *The state table*, *What every
+  transition does* and *The verbs*.