diff --git a/.changeset/20283-object-timeline-items-element-owner-describe.md b/.changeset/20283-object-timeline-items-element-owner-describe.md
new file mode 100644
index 00000000000..1fe51f3ad3d
--- /dev/null
+++ b/.changeset/20283-object-timeline-items-element-owner-describe.md
@@ -0,0 +1,7 @@
+---
+"@objectstack/spec": patch
+---
+
+`ObjectTimelinePropsSchema.items`' describe no longer says "the author owns the item shape". `items` stays `z.array(z.unknown())` — no schema-shape change — but the sentence now names the actual owner: each element is objectui's declared timeline element, `@object-ui/types`'s `TimelineFeedItem` (`variant` absent / `vertical` / `horizontal`) or `TimelineGanttItem` (`variant: 'gantt'`), the arm this node's `variant` selects.
+
+The element union is declared entirely inside objectui's `packages/types` (`TimelineFeedItem` / `TimelineGanttItem`, plain TypeScript interfaces) — nothing in this package imports or re-declares it, so this is a documentation-only correction, not a value-tightening. Value tightening (declaring the arms in this schema instead of `z.unknown()`) stays a later ratchet with its own inventory.
diff --git a/content/docs/references/ui/component.mdx b/content/docs/references/ui/component.mdx
index fa285bc05d5..825a9343ef4 100644
--- a/content/docs/references/ui/component.mdx
+++ b/content/docs/references/ui/component.mdx
@@ -991,7 +991,7 @@ View filter rule
 | **sort** | `{ field: string; order: Enum<'asc' \| 'desc'> }[]` | optional | Row order for the fetched entries — the SortItem array form `[{ field, order }, ...]`, the one sort orthography every declared `sort` door on this platform shares; lowered to the wire `$orderby`. The legacy string clause (`name desc`) is refused — see migration `object-block-sort-item-array` |
 | **limit** | `integer` | optional | Maximum number of records loaded onto the rail (row cap); lowered to the query's top-level `$top` (renderer default 100). A timeline renders one rail with no pagination control, so this is the author's window rather than a page size |
 | **data** | `any[]` | optional | Pre-fetched records — read FIRST as the rail's row source, ahead of the data-scope binding and the fetch, and composed into entries through the same `timeline` field bindings a fetched row takes; authoring it suppresses the object query entirely. Distinct from `items`, which is the already-composed entry shape and wins over this key when both are written |
-| **items** | `any[]` | optional | Static inline entries — read ahead of every record source, `data` above included, and bypasses the object query entirely (the renderer becomes a pass-through and the author owns the item shape) |
+| **items** | `any[]` | optional | Static inline entries — read ahead of every record source, `data` above included, and bypasses the object query entirely (the renderer becomes a pass-through). Each element is objectui's declared timeline element, `@object-ui/types`'s `TimelineFeedItem` (`variant` absent / `vertical` / `horizontal`) or `TimelineGanttItem` (`variant: 'gantt'`), the arm this node's `variant` selects |
 | **variant** | `Enum<'vertical' \| 'horizontal' \| 'gantt'>` | optional | Rail layout (renderer default `vertical`). ⚠️ `gantt` needs authored `items`: the object-bound path composes flat feed entries, which the gantt branch cannot draw, and refuses that combination with a named diagnostic instead of drawing an empty chart |
 | **dateFormat** | `Enum<'short' \| 'long' \| 'iso'>` | optional | How each entry's date is rendered (renderer default `short`): `short` / `long` are locale-formatted, `iso` is the locale-free machine form |
 | **rowLabel** | `string` | optional | Header label for the gantt row column — read by the gantt branch only, which on this block needs authored `items` |
diff --git a/packages/spec/src/ui/component.zod.ts b/packages/spec/src/ui/component.zod.ts
index d133710476d..1fb93dca91b 100644
--- a/packages/spec/src/ui/component.zod.ts
+++ b/packages/spec/src/ui/component.zod.ts
@@ -5207,7 +5207,7 @@ export const ObjectTimelinePropsSchema = lazySchema(() => strictObject({
   data: z.array(z.unknown()).optional()
     .describe("Pre-fetched records — read FIRST as the rail's row source, ahead of the data-scope binding and the fetch, and composed into entries through the same `timeline` field bindings a fetched row takes; authoring it suppresses the object query entirely. Distinct from `items`, which is the already-composed entry shape and wins over this key when both are written"),
   items: z.array(z.unknown()).optional()
-    .describe('Static inline entries — read ahead of every record source, `data` above included, and bypasses the object query entirely (the renderer becomes a pass-through and the author owns the item shape)'),
+    .describe("Static inline entries — read ahead of every record source, `data` above included, and bypasses the object query entirely (the renderer becomes a pass-through). Each element is objectui's declared timeline element, `@object-ui/types`'s `TimelineFeedItem` (`variant` absent / `vertical` / `horizontal`) or `TimelineGanttItem` (`variant: 'gantt'`), the arm this node's `variant` selects"),
   variant: z.enum(['vertical', 'horizontal', 'gantt']).optional()
     .describe("Rail layout (renderer default `vertical`). ⚠️ `gantt` needs authored `items`: the object-bound path composes flat feed entries, which the gantt branch cannot draw, and refuses that combination with a named diagnostic instead of drawing an empty chart"),
   dateFormat: z.enum(['short', 'long', 'iso']).optional()