spec(ui): retire `PageHeaderProps.breadcrumb` ("Show breadcrumb", default true) — no renderer draws a trail and the console shell already draws one; the spec half of objectui#11166

[objectstack-fleet]

Filed by the triage seat (objectstack-wide, seat post #6015, session_01AavokzJ5DndAwitDXvKy4U) as the spec half of objectstack-ai/objectui#11166, per that card's first grade. ⛔ Not a claim, ⛔ not a dispatch. Graded here: enhancement · priority:p3 · domain:spec · area:records · pm:queue.

What is declared, and what honours it

• packages/spec/src/ui/component.zod.ts PageHeaderProps (strictObject, about :450) declares breadcrumb: z.boolean().default(true).describe('Show breadcrumb') (about :518).
• objectui's PageHeaderRenderer (packages/components/src/renderers/layout/containers.tsx) reads the key and draws an empty div[data-page-breadcrumb-slot] in both layouts. No code fills it (measured by the objectui#3906 dev at objectui PR driver-sql (PG): introspectPrimaryKeys reports a covering primary key's INCLUDE'd columns as key members — indkey is read whole, indnkeyatts is ignored #11162's head, and confirmed by that PR's contract review).
• The console already draws the navigation trail once, in the shell: @object-ui/app-shell's AppHeader renders the breadcrumb path inside /apps/:appName/*.

Ruling (triage, under the standing rule #18900 A′④: 「有 ⇒ 补消费端;没有 ⇒ 退役」)

RETIRE. The key has no consumer. The default-true slot has rendered empty on every page header without anyone missing a trail, and the trail it would draw is the shell's. So a renderer would duplicate the shell, not supply something missing.

• This card (spec): retire breadcrumb from PageHeaderProps through the ADR-0087 route, the way icon was retired from the same row (ADR-0087 D2). An authored breadcrumb (true or false) on a stored or bundled page loads with the key stripped and the ADR-0087 notice. ⛔ It is never a hard refusal of an existing page. The generated artefacts, forms and docs the retirement playbook lists move in the same PR.
• The objectui half (objectui#11166): the renderer stops reading the key and drops the empty slot. The docs stop showing the key. That half lands after this one reaches objectui's install face, or reads the key defensively until it does.
• Same family, measured by this card, not assumed: the spec also declares a nav:breadcrumb component (emptyProps, about :5311), and objectui has no renderer for it (git grep "nav:breadcrumb" over objectui packages/*/src: 0 hits). The dev measures whether any producer writes it. With none, it retires under the same rule in the same PR. With one, the report names it and it stays.
• Clause-②: yes (a key leaves a published strictObject). The ADR-0087 conversion keeps stored pages loading, and the changeset carries the BREAKING banner the playbook requires.
• Pins:
  • a page header authored with breadcrumb: true and one with breadcrumb: false both load, with the key stripped and the notice recorded;
  • the ADR-0087 ledger row is present;
  • a page header without the key is unchanged (the control).

If the maintainer wants a page-level trail after all (for example on pages outside /apps/*, where the shell draws none), that is ENFORCE: a renderer in objectui plus a real trail source. Say so on this card and it is re-graded. The ruling above reflects no measured pull today.

Dedupe: this repo's issues were searched for breadcrumb PageHeaderProps (0 hits, as the objectui card also recorded) and nav:breadcrumb (0 open cards on it).

[objectstack-fleet]

Claim: PM loop round 17 · 2026-09-30T04:03Z
Session: session_01Sfe5YjBLwB9J3y8fvm2xq1
Account: os-justin (the seat's linked user as GET /user answers it; the card's assignee from this act)
Branch: claude/issue-20758-page-header-breadcrumb-retired
Worktree: objectstack-issue-20758
Domain: domain:spec
Seat: domain:spec#5 (seat post #19357)
Clause-②: no (narrowing). The card's triage section declares the plain widening arm. A key leaving a published strictObject narrows the accept set and widens nothing the seat can name, so the seat declares no (narrowing), with the BREAKING banner and the ADR-0087 disposition, as on #20637 (PR #20710). If the diff widens something, the report names it and the line becomes yes (narrowing).
Direction: the card's RETIRE ruling, taken whole. breadcrumb leaves PageHeaderProps through the ADR-0087 route. A stored or bundled page with breadcrumb (true or false) loads with the key stripped and a notice, and is ⛔ never hard-refused. nav:breadcrumb retires in the same PR only if the dev measures no producer. With a producer, the report names it and it stays. The card's three pins.
File surface (stop on breach and explain it in the report):

• packages/spec/src/ui/component.zod.ts: PageHeaderProps (:450, breadcrumb at :518). If nav:breadcrumb retires: its ComponentPropsMap row (:5311) and the list in the comment at :342.
• packages/spec/src/ui/page.zod.ts:159, the component-type list that names nav:breadcrumb, only if it retires.
• The ADR-0087 disposition: the D2 conversion and its registry rows, a D3 entry if the playbook asks for one, and the STEP18_RATIONALE fragment. migrations/registry.ts is also edited by the open PR chore(objectui): bump the console pin to db11afd4967c (carries objectui#11119, the objectui#11105 fix) #20706; it is generated, and whoever lands later regenerates.
• Generated baselines, regenerated only: authorable-defaults/ui.json:78, authorable-surface.base.json:7564, authorable-surface/ui.json:1098, and every other artefact the retirement playbook lists.
• Pins that assert or enumerate what this change removes: src/ui/component.test.ts:39-72 (the breadcrumb default) and :1335, and scripts/format-type.test.ts:1378. The dev runs the census that completes this list.
• Texts that describe what this change removes: content/docs/protocol/objectui/layout-dsl.mdx:61 ("page:header (title, actions, breadcrumb)"), content/docs/ui/pages.mdx:184 (lists nav:breadcrumb), and the generated content/docs/references/ui/{component,page}.mdx. The seat's census is not complete; the dev owns it.
• .changeset/20758-*.md.
• ⛔ No objectui edit: [seam] page:header's breadcrumb ("Show breadcrumb", default true) draws only an empty slot — the declared capability is never honoured objectui#11166 is that half. ⛔ No docs/adr/** (governed).
  Container & model: M, mode:subagent, model: opus.
  Review: an at-tier contract review is owed before enqueue.
  Thread-read: none
  Serial constraints cleared: read at this stamp.
• This seat's PR fix(spec)!: a time value carries no zone — ClockTimeValueSchema refuses a Z or an offset, with an ADR-0087 disposition for stored defaults (#20740) #20763 (conversions/registry.ts, migrations/registry.ts) landed as c9c182ed14.
• PR chore(objectui): bump the console pin to db11afd4967c (carries objectui#11119, the objectui#11105 fix) #20706 edits component.zod.ts, but none of its hunks touches PageHeaderProps or :5311, and it edits the generated migrations/registry.ts. That is ordinary concurrency.
• This seat's PR docs(spec): replace the dead tracker citations in the manifest, dataset and permission liveness ledgers with the deciding commit, or the decision in words #20772 touches only three liveness ledgers, none of which has a breadcrumb row.

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