@@ -0,0 +1,80 @@
+---
+"@objectstack/spec": minor
+---
+
+feat(spec)!: retire the `inline` and `grid` arms of form `layout` — every renderer folded both to `vertical`, and multi-column is `columns` (ADR-0049)
+
+<!-- adr-0087: registered form-layout-inline-grid-to-vertical, ui-form-layout-inline-grid-retired -->
+
+**BREAKING** — form `layout` accepts exactly `'vertical' | 'horizontal'` on both surfaces
+that declared the four-arm enum: the `object-form` page component
+(`ObjectFormPropsSchema.layout`) and the form view (`FormViewSchema.layout` — `view.form`,
+`view.formViews.*`, a form view item's `config`, and the flattened form overlay, which
+spreads the form view's shape). `'inline'` and `'grid'` are refused at parse, each with a
+prescription naming what to write instead.
+
+| surface | before | after |
+|:--|:--|:--|
+| `object-form` `layout: 'grid'` | parsed clean, rendered as `vertical` | refused — write `'vertical'` (or omit `layout`); for multi-column set `columns` |
+| `object-form` `layout: 'inline'` | parsed clean, rendered as `vertical` | refused — write `'vertical'` (or omit `layout`) |
+| form view `layout: 'grid'` | parsed clean, rendered as `vertical` | refused — write `'vertical'` (or omit `layout`); for multi-column set `columns` |
+| form view `layout: 'inline'` | parsed clean, rendered as `vertical` | refused — write `'vertical'` (or omit `layout`) |
+| `layout: 'vertical'` / `'horizontal'` | accepted | **unchanged** |
+| `columns` | honoured under every layout | **unchanged** — the key multi-column always lived under |
+
+**What was actually wrong.** No renderer ever gave either value a behaviour of its own.
+Measured at the `.objectui-sha` pin this repo builds against (`f8a9d0fb0`): the simple
+`object-form` arm folds both to `vertical` (`ObjectForm.tsx:1406-1410`, under the comment
+"Map 'grid' and 'inline' to 'vertical' as fallback"); the drawer and modal arms
+(`ObjectForm.tsx:463`, `:499`) and `DrawerForm.tsx:575` / `ModalForm.tsx:597` pass only
+`vertical` / `horizontal` through; `TabbedForm.tsx:556`, `SplitForm.tsx:445` and
+`WizardForm.tsx:1075` hard-code `vertical`. So both values were a green parse for a value the
+renderer threw away. The spec had admitted them from two declarations — the designer palette
+and the registry `inputs` offered all four — never from a read.
+
+Under the maintainer's ADR-0049 family criterion (the capability exists on mainstream
+platforms ⇒ build the consumer; it does not ⇒ retire), multi-column — what `grid` would
+mean — already exists here under another key, `columns`, which the renderer honours under
+every arm; `inline` is a toolbar / filter-row pattern, not a record-form layout. The two arms
+are redundant vocabulary, retired with no alias window.
+
+## What to write instead
+
+```ts
+// before — parsed clean, rendered single-column 'vertical'
+{ type: 'object-form', properties: { objectName: 'crm_lead', layout: 'grid' } }
+// after — what it rendered; add `columns` if a multi-column form was the intent
+{ type: 'object-form', properties: { objectName: 'crm_lead', layout: 'vertical', columns: 2 } }
+```
+
+`'inline'` → `'vertical'` (or delete `layout`: `'vertical'` is the renderer default). A form
+that wrote `'grid'` without `columns` always rendered single-column; only its author knows
+whether more columns were meant — set `columns` to the count you meant.
+
+Existing sources: `os migrate meta --from 17` lists the mechanical edits; apply them by hand.
+
+The retirement kit:
+
+- both enums narrowed to `'vertical' | 'horizontal'`, each with a per-value error map keyed on
+  the input (the `record:chatter` `position` precedent), so only a value that used to be legal
+  is told it "was removed"; a never-vocabulary value keeps zod's own enum refusal
+- the D2 conversion `form-layout-inline-grid-to-vertical` (protocol 18, retired from the load
+  path) rewrites both values to `'vertical'` and leaves `columns` untouched — on `object-form`
+  page components, on every form payload a view carries, and on the assembled-manifest
+  `viewItems` channel, so stored rows and assembled artifacts replay clean; wired into the
+  protocol-18 chain step
+- one D3 entry for the family, `ui-form-layout-inline-grid-retired`, carrying the one judgement
+  the chain cannot make: whether a form that said `grid` wanted columns it never declared
+- pin tests (`ui/form-layout-inline-grid-retired.test.ts`): both values refused with the
+  prescription on five doors (`ObjectFormPropsSchema`, the `object-form` props-map row,
+  `FormViewSchema`, a view container's `formViews`, the flattened form overlay), `vertical` /
+  `horizontal` green on each as controls, the conversion's rewrite parsing green on the door
+  that refused its input, and the chain registration
+- the `columns` descriptions no longer say "grid layout"; the generated references
+  (`content/docs/references/**`, `skills/objectstack-ui/references/react-blocks.md`, the JSON
+  Schema) print the two-arm enum; the hand-written `layout-dsl` page and the `form.layout`
+  liveness row (still `live`) are updated
+- `api-surface/` and `authorable-surface/` are unchanged, correctly: they ratchet export and
+  key existence, and no export or key leaves — `layout` is still declared, two values narrower
+
+Clause-②: no (narrowing)
@@ -544,8 +544,8 @@ The tab *is* the section, so a section's keys are the whole surface: `name`,
 `visibleWhen` — plus `pane`, which split forms alone accept. There is **no**
 per-tab `lazy`, `source`, `badge` or `badgeVariant` key, and no
 `layout: { mode: tabbed, ... }` wrapper: `FormViewSchema.layout` is a string
-enum (`vertical` / `horizontal` / `inline` / `grid`) and the form schema
-declares no `tabs` key at all. `FormViewSchema` and `FormSectionSchema`
+enum (`vertical` / `horizontal` — multi-column is the separate `columns` key,
+not a layout value) and the form schema declares no `tabs` key at all. `FormViewSchema` and `FormSectionSchema`
 (`packages/spec/src/ui/view.zod.ts`) are `.strict()`, so authoring any of them
 is a **parse failure** — a loud rejection, not a silent no-op.
 
 
@@ -1644,9 +1644,9 @@ The published metadata item body, opaque by ruling (1C). Shape is the item's own
 | **label** | `string \| Record<string, string>` | optional | Human-readable label shown in metadata lists. |
 | **object** | `string` | optional | Object this container binds to — how a stack-level `views: [...]` entry says which object its views belong to; read by `getViewsByObject()` / `GET /meta/view?object=`. |
 | **list** | `{ name?: string; label?: string \| Record<string, string>; type?: Enum<'grid' \| 'kanban' \| 'gallery' \| 'calendar' \| 'timeline' \| 'gantt' \| 'map' \| 'chart' \| 'tree'>; data?: object \| … +3 more; … }` | optional |  |
-| **form** | `{ type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>; columns?: integer; title?: string; … }` | optional |  |
+| **form** | `{ type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal'>; columns?: integer; title?: string; … }` | optional |  |
 | **listViews** | `Record<string, { name?: string; label?: string \| Record<string, string>; type?: Enum<'grid' \| 'kanban' \| 'gallery' \| 'calendar' \| 'timeline' \| 'gantt' \| 'map' \| 'chart' \| 'tree'>; data?: object \| … +3 more; … }>` | optional | Additional named list views (views mode — dropdown userFilters allowed, no tabs; ADR-0047) |
-| **formViews** | `Record<string, { type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>; columns?: integer; title?: string; … }>` | optional | Additional named form views |
+| **formViews** | `Record<string, { type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal'>; columns?: integer; title?: string; … }>` | optional | Additional named form views |
 | **protection** | `{ lock: Enum<'none' \| 'no-overlay' \| 'no-delete' \| 'full'>; reason: string; docsUrl?: string }` | optional | Package author protection block — lock policy for this view. |
 | **_lock** | `Enum<'none' \| 'no-overlay' \| 'no-delete' \| 'full'>` | optional | Item-level lock — controls overlay & delete (ADR-0010). |
 | **_lockReason** | `string` | optional | Human-readable reason shown when a write is refused by _lock. |
@@ -1716,7 +1716,7 @@ The published metadata item body, opaque by ruling (1C). Shape is the item's own
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **type** | `Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>` | optional (default: `"simple"`) |  |
-| **layout** | `Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>` | optional | Field layout direction |
+| **layout** | `Enum<'vertical' \| 'horizontal'>` | optional | Field layout direction — 'vertical' (the renderer default) or 'horizontal'. Multi-column is not a layout value: set `columns` |
 | **columns** | `integer` | optional | Number of columns for the form body |
 | **title** | `string` | optional | Form title |
 | **description** | `string` | optional | Form description |
@@ -1801,7 +1801,7 @@ The published metadata item body, opaque by ruling (1C). Shape is the item's own
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **type** | `Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>` | optional (default: `"simple"`) |  |
-| **layout** | `Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>` | optional | Field layout direction |
+| **layout** | `Enum<'vertical' \| 'horizontal'>` | optional | Field layout direction — 'vertical' (the renderer default) or 'horizontal'. Multi-column is not a layout value: set `columns` |
 | **columns** | `integer` | optional | Number of columns for the form body |
 | **title** | `string` | optional | Form title |
 | **description** | `string` | optional | Form description |
 
@@ -362,8 +362,8 @@ Sort field and direction pair
 | **recordId** | `string \| number` | optional | Record to load (edit/view modes) |
 | **mode** | `Enum<'create' \| 'edit' \| 'view'>` | optional | Form mode |
 | **formType** | `Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>` | optional | Form presentation |
-| **layout** | `Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>` | optional | Field layout |
-| **columns** | `number` | optional | Field columns in grid layout |
+| **layout** | `Enum<'vertical' \| 'horizontal'>` | optional | Field layout — 'vertical' (the renderer default) or 'horizontal'. Multi-column is not a layout value: set `columns` |
+| **columns** | `number` | optional | Number of field columns (multi-column forms), honoured under either `layout` |
 | **fields** | `any[]` | optional | Limit/order the fields shown |
 | **customFields** | `any` | optional | Custom field definitions merged into the generated set |
 | **sections** | `any[]` | optional | Form sections (`{ label, description?, fields }` — wizard steps / tab panes) |
 
@@ -401,7 +401,7 @@ Form-view select option — the object-field option shape minus the per-option `
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **type** | `Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>` | optional (default: `"simple"`) |  |
-| **layout** | `Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>` | optional | Field layout direction |
+| **layout** | `Enum<'vertical' \| 'horizontal'>` | optional | Field layout direction — 'vertical' (the renderer default) or 'horizontal'. Multi-column is not a layout value: set `columns` |
 | **columns** | `integer` | optional | Number of columns for the form body |
 | **title** | `string` | optional | Form title |
 | **description** | `string` | optional | Form description |
@@ -1778,9 +1778,9 @@ Tab configuration for multi-tab view interface
 | **label** | `string \| Record<string, string>` | optional | Human-readable label shown in metadata lists. |
 | **object** | `string` | optional | Object this container binds to — how a stack-level `views: [...]` entry says which object its views belong to; read by `getViewsByObject()` / `GET /meta/view?object=`. |
 | **list** | `{ name?: string; label?: string \| Record<string, string>; type?: Enum<'grid' \| 'kanban' \| 'gallery' \| 'calendar' \| 'timeline' \| 'gantt' \| 'map' \| 'chart' \| 'tree'>; data?: object \| … +3 more; … }` | optional |  |
-| **form** | `{ type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>; columns?: integer; title?: string; … }` | optional |  |
+| **form** | `{ type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal'>; columns?: integer; title?: string; … }` | optional |  |
 | **listViews** | `Record<string, { name?: string; label?: string \| Record<string, string>; type?: Enum<'grid' \| 'kanban' \| 'gallery' \| 'calendar' \| 'timeline' \| 'gantt' \| 'map' \| 'chart' \| 'tree'>; data?: object \| … +3 more; … }>` | optional | Additional named list views (views mode — dropdown userFilters allowed, no tabs; ADR-0047) |
-| **formViews** | `Record<string, { type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>; columns?: integer; title?: string; … }>` | optional | Additional named form views |
+| **formViews** | `Record<string, { type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal'>; columns?: integer; title?: string; … }>` | optional | Additional named form views |
 | **protection** | `{ lock: Enum<'none' \| 'no-overlay' \| 'no-delete' \| 'full'>; reason: string; docsUrl?: string }` | optional | Package author protection block — lock policy for this view. |
 | **_lock** | `Enum<'none' \| 'no-overlay' \| 'no-delete' \| 'full'>` | optional | Item-level lock — controls overlay & delete (ADR-0010). |
 | **_lockReason** | `string` | optional | Human-readable reason shown when a write is refused by _lock. |
@@ -1850,7 +1850,7 @@ Tab configuration for multi-tab view interface
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **type** | `Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>` | optional (default: `"simple"`) |  |
-| **layout** | `Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>` | optional | Field layout direction |
+| **layout** | `Enum<'vertical' \| 'horizontal'>` | optional | Field layout direction — 'vertical' (the renderer default) or 'horizontal'. Multi-column is not a layout value: set `columns` |
 | **columns** | `integer` | optional | Number of columns for the form body |
 | **title** | `string` | optional | Form title |
 | **description** | `string` | optional | Form description |
@@ -1935,7 +1935,7 @@ Tab configuration for multi-tab view interface
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **type** | `Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>` | optional (default: `"simple"`) |  |
-| **layout** | `Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>` | optional | Field layout direction |
+| **layout** | `Enum<'vertical' \| 'horizontal'>` | optional | Field layout direction — 'vertical' (the renderer default) or 'horizontal'. Multi-column is not a layout value: set `columns` |
 | **columns** | `integer` | optional | Number of columns for the form body |
 | **title** | `string` | optional | Form title |
 | **description** | `string` | optional | Form description |
@@ -2187,7 +2187,7 @@ This schema accepts one of the following structures:
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **viewKind** | `'form'` | ✅ |  |
-| **config** | `{ type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>; columns?: integer; title?: string; … }` | ✅ | Form view configuration. |
+| **config** | `{ type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal'>; columns?: integer; title?: string; … }` | ✅ | Form view configuration. |
 | **name** | `string` | ✅ | Globally-unique view id, `<object>.<viewKey>`. |
 | **object** | `string` | ✅ | Bound object name — the foreign key used to aggregate views. |
 | **label** | `string \| Record<string, string>` | optional | Display label (supports i18n). |
@@ -2210,7 +2210,7 @@ This schema accepts one of the following structures:
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **type** | `Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>` | optional (default: `"simple"`) |  |
-| **layout** | `Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>` | optional | Field layout direction |
+| **layout** | `Enum<'vertical' \| 'horizontal'>` | optional | Field layout direction — 'vertical' (the renderer default) or 'horizontal'. Multi-column is not a layout value: set `columns` |
 | **columns** | `integer` | optional | Number of columns for the form body |
 | **title** | `string` | optional | Form title |
 | **description** | `string` | optional | Form description |
@@ -2370,7 +2370,7 @@ This schema accepts one of the following structures:
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **viewKind** | `'form'` | ✅ |  |
-| **config** | `{ type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>; columns?: integer; title?: string; … }` | ✅ | Form view configuration. |
+| **config** | `{ type?: Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>; layout?: Enum<'vertical' \| 'horizontal'>; columns?: integer; title?: string; … }` | ✅ | Form view configuration. |
 | **name** | `string` | ✅ | Globally-unique view id, `<object>.<viewKey>`. |
 | **object** | `string` | ✅ | Bound object name — the foreign key used to aggregate views. |
 | **label** | `string \| Record<string, string>` | optional | Display label (supports i18n). |
@@ -2396,7 +2396,7 @@ This schema accepts one of the following structures:
 | Property | Type | Required | Description |
 | :--- | :--- | :--- | :--- |
 | **type** | `Enum<'simple' \| 'tabbed' \| 'wizard' \| 'split' \| 'drawer' \| 'modal'>` | optional (default: `"simple"`) |  |
-| **layout** | `Enum<'vertical' \| 'horizontal' \| 'inline' \| 'grid'>` | optional | Field layout direction |
+| **layout** | `Enum<'vertical' \| 'horizontal'>` | optional | Field layout direction — 'vertical' (the renderer default) or 'horizontal'. Multi-column is not a layout value: set `columns` |
 | **columns** | `integer` | optional | Number of columns for the form body |
 | **title** | `string` | optional | Form title |
 | **description** | `string` | optional | Form description |
 
@@ -264,7 +264,8 @@
         },
         "layout": {
           "status": "live",
-          "note": "objectui: ObjectForm.tsx:826, ModalForm.tsx:468, DrawerForm.tsx:384 (vertical/horizontal)."
+          "verifiedAt": "2026-09-27",
+          "note": "objectui @ f8a9d0fb0: plugin-form ObjectForm.tsx:1408 (simple arm) and :463/:499 (drawer/modal hand-off), DrawerForm.tsx:575, ModalForm.tsx:597 — each reads vertical/horizontal only. The enum was narrowed to those two arms 2026-09-27 (#20221, ADR-0049 enforce-or-remove): every arm folded 'inline' and 'grid' to vertical, so both were a declared value the renderer threw away; multi-column is the sibling `columns` key. The key itself stays live."
         },
         "columns": {
           "status": "live",