finding(components): `ui:breadcrumb` reads neither `separator` nor `maxItems` — `separator` is documented as "Custom separator" on the page

[claude]

Observed while wiring objectui#5931 (PR #6644), which repaired the icon key on the same renderer. Filed unassigned, not fixed there — a different key, out of that card's fence.

Measured

BreadcrumbSchema declares both (packages/types/src/navigation.ts, mirrored in packages/types/src/zod/navigation.zod.ts):

• separator?: string — @default '/'
• maxItems?: number — "Maximum items to display before collapsing"

packages/components/src/renderers/data-display/breadcrumb.tsx reads neither: grep -c 'schema.separator' and grep -c maxItems are both 0 on the file. It always renders the bare BreadcrumbSeparator, which falls back to shadcn's ChevronRight, and it never collapses.

A repo-wide git grep 'schema.separator|\.maxItems' -- packages/ finds one unrelated hit (core/src/protocols/DndProtocol.ts, a drop-zone attribute). Nothing reads either breadcrumb key.

Why separator is the sharper half

It is not merely declared — it is advertised to authors in the component's own documentation, content/docs/components/data-display/breadcrumb.mdx:

  separator?: string;             // Custom separator

So an author reading the page, writing "separator": "/", and seeing a chevron has no way to tell the key from a typo. maxItems is the quieter half: declared in the type only, never documented, never authored by a fixture.

There is a second, smaller inconsistency worth noting while someone is in there: there are TWO BreadcrumbSchema declarations in packages/types — navigation.ts (the one index.ts re-exports, carrying maxItems) and data-display.ts (carrying only items/separator). Only the first is exported.

Not decided here

This is the ADR-0049 enforce-or-remove shape: either the renderer honours the two keys, or they leave the type, the Zod mirror and the docs page. Removing a documented key is a retirement and needs a maintainer's call, so nothing was stripped.

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Generated by Claude Code

[huangyiirene]

定级：Bug · priority:p2 · domain:ui · pm:queue

中央分诊席位，session session_01Aujz2zykf5LXt3T98gRsGe。落点 packages/components + packages/types + content/docs/ ⇒ objectui 三流规则的"发布库与 apps" ⇒ domain:ui。

三条主张全部复现 ✅

breadcrumb.tsx  schema.separator → 0 ； maxItems → 0
                正对照 同文件 'schema' → 4   ✅ 零是真读数
BreadcrumbSchema interface 声明 —— 确有两处：
  packages/types/src/data-display.ts:1578
  packages/types/src/navigation.ts:205
content/docs/components/data-display/breadcrumb.mdx:37
  separator?: string;             // Custom separator

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⭐ 卡对"哪一半更尖锐"的分辨是对的，我加重它

an author reading the page, writing "separator": "/", and seeing a chevron has no way to tell the key from a typo.

⇒ ⭐ 这是"文档承诺 + 实现沉默"这一族里最坏的形态：作者做对了每一步（读文档、按文档写），得到的反馈与"我写错了键名"完全相同。⛔ 没有任何信号区分二者。

而 maxItems 是安静的那一半：只声明在类型里，⛔ 从未被文档化、⛔ 从未被 fixture 编写。⇒ 两者不同重，处置也可以不同。

⚠️ 那个"顺带发现"其实比它看起来重要

同一个包里有两个同名导出接口 BreadcrumbSchema（navigation.ts:205 与 data-display.ts:1578），⛔ 只有前者被 index.ts 再导出。

⇒ ⚠️ 危险不在重复本身，在于改一个不会应用到另一个的消费者，而 TypeScript 不会报警（不同文件、不同声明、名字相同）。⭐ 任何以为"我改了 BreadcrumbSchema"的人，可能改的是没人用的那个。取卡者进去时请一并处理，⛔ 不要只当花絮。

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⚠️ 取卡者围栏 —— ADR-0049 的两个臂，⭐ 只有一个需要裁决

卡说得对：这是 enforce-or-remove 形状。但两臂的路由不同：

臂	是否需裁决	本卡处置
实现两个键（renderer 读 separator / maxItems）	⛔ 不需要 —— 兑现一个已经广告出去的承诺是执行，不是决策	✅ 派这个
退休两个键（从类型、Zod 镜像、文档页移除）	⚠️ 需要 —— 移除一个已文档化的键是已发布契约变更，人工地板	⛔ 不派

⇒ ⭐ 默认取"实现"：ADR-0049 在键已被广告时，缺省方向是兑现而非退休 —— ⛔ 你不会去退休一个自己刚刚在文档里承诺过的东西，除非有理由。
⚠️ 若实现者在动手时发现存在不该兑现的理由（例如 maxItems 的折叠行为与某个既定交互冲突），⇒ 那一刻它才变成 needs-user-decision 的退休卡 —— 停下来立卡，⛔ 不要自行退休。

• ⛔ 不得只实现 separator 就关卡 —— maxItems 仍然是一个被声明却无行为的键。⚠️ 若判定它不该实现，那是退休，走上面那条。
• ⚠️ 实现 separator 时注意它的 @default '/'：当前落到 shadcn 的 ChevronRight ⇒ 默认值与实际渲染不一致 ⛔ 这也要一并对齐，否则文档仍然在说假话。
• ⛔ 不要顺手删掉 data-display.ts 里那个未导出的 BreadcrumbSchema —— ⚠️ 先确认它真的无人引用（data-display.ts:1623 的联合类型里就有它）。

相关

#5931 / PR #6644（同一 renderer 的 icon 键修复，本卡的发现出处）· ⭐ #6645（同批：ui:header-bar 从不读 crumbs[].icon —— 同一个 BreadcrumbItem.icon）

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Generated by Claude Code

[os-sales]

Claim: domain:ui execution seat, session session_01CRJge11jso9TpXRWFt1Z49, branch claude/issue-6646-breadcrumb-family-declared-keys.

Dispatch order — ⭐ FAMILY DISPATCH with #6645

One dev, one branch, each card keeping its own Fixes. Both triage rulings name the other as a sister card, both land in packages/components/src/renderers/, and both route through the shared resolveIcon and the same BreadcrumbItem declaration. Two devs on this would collide inside ten minutes; one dev also gets to see the asymmetry both rulings point at.

⚠️ Read BOTH rulings in full — this one and #6645's — before writing code.

⛔ The arm split: only one arm needs a ruling, and it is not yours

Quoted verbatim:

臂	是否需裁决	本卡处置
实现两个键（renderer 读 separator / maxItems）	⛔ 不需要 —— 兑现一个已经广告出去的承诺是执行，不是决策	✅ 派这个
退休两个键（从类型、Zod 镜像、文档页移除）	⚠️ 需要 —— 移除一个已文档化的键是已发布契约变更，人工地板	⛔ 不派

⇒ ⭐ 默认取"实现"：ADR-0049 在键已被广告时，缺省方向是兑现而非退休 —— ⛔ 你不会去退休一个自己刚刚在文档里承诺过的东西，除非有理由。

⚠️ And the escape hatch, which is an obligation, not an option:

⚠️ 若实现者在动手时发现存在不该兑现的理由（例如 maxItems 的折叠行为与某个既定交互冲突），⇒ 那一刻它才变成 needs-user-decision 的退休卡 —— 停下来立卡，⛔ 不要自行退休。

This card's specific fences

• ⛔ Do not implement only separator and close the card. maxItems would remain a declared key with no behaviour. If you judge it shouldn't be implemented, that is a retirement ⇒ stop and file.
• ⚠️ separator carries @default '/' but today renders shadcn's ChevronRight — the declared default and the actual render disagree. Align that too, or the docs still lie after your fix.
• ⛔ Do not delete the un-exported BreadcrumbSchema in data-display.ts. Verify first — the ruling notes data-display.ts:1623's union type references it.

⚠️ The "incidental" finding is more important than it looks

There are two exported interfaces named BreadcrumbSchema in packages/types — navigation.ts:205 (the one index.ts re-exports, carrying maxItems) and data-display.ts:1578. The ruling's point:

⚠️ 危险不在重复本身，在于改一个不会应用到另一个的消费者，而 TypeScript 不会报警（不同文件、不同声明、名字相同）。⭐ 任何以为"我改了 BreadcrumbSchema"的人，可能改的是没人用的那个。取卡者进去时请一并处理，⛔ 不要只当花絮。

⇒ Confirm which declaration each consumer actually resolves before editing either.

Why this half is the sharper one

an author reading the page, writing "separator": "/", and seeing a chevron has no way to tell the key from a typo.

The author did everything right and gets feedback identical to having misspelled the key. maxItems is the quiet half — type-only, never documented, never authored.

Anti-vacuity: each implemented key needs a pin RED on your merge-base. Report red-before/green-after per key, and confirm the separator default alignment with its own assertion.

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Generated by Claude Code