docs: classify Ebox DSL primitives and sugar

AGENTS.md

@@ -20,6 +20,9 @@ ETAF 当前性能工作的最终结果是：通用性能工具能解释每次操
   不把偶然的调用顺序、示例名称或当前数据形状伪装成抽象。
 - 一个模块只拥有一项完整职责，并为这项职责提供少量、精确、正交的接口。
   接口之间通过明确数据契约组合，不读取彼此的内部状态，不复制彼此的规则。
+- 用户心智成本是公共 API 的硬指标。同一能力只能有一个规范名称和一条推荐路径；
+  内部算法、后端节点、兼容别名和便捷 wrapper 不得伪装成并列公共概念。常用路径
+  只要求学习最小模型，高级能力通过逐层展开获得，不能让用户先理解包内部实现。
 - 区分语义身份、视觉槽位、布局坐标、绘制层和发布权限。只有模型本身允许时
   才能合并概念；不能为了减少代码把不同生命周期的身份混在一起。
 - 复杂系统通过小模块的组合与复用逐步形成。新增能力应优先扩展已有模型的

docs/proposals/module-boundaries.en.md

@@ -8,6 +8,11 @@ This document defines only the target model, module owners, dependency direction
 completion criteria. Delivery sequencing belongs in a separate implementation plan;
 historical names and compatibility do not shape the target architecture.
 
+User mental cost is a hard constraint: one capability has one canonical name and one
+recommended spelling. Internal algorithms, backend nodes, wrappers, and compatibility
+aliases never become peer public concepts. Ordinary applications learn Text, Box, and
+Component first; Fragment, layout detail, and lower packages are progressively disclosed.
+
 ## 1. Final model
 
 ```text
@@ -92,7 +97,51 @@ child's `:outer` does not change ordering. `:outer` is consumed only by a normal
 They are Box modes, not Components or alternate Runtime node names. The only canonical
 surface is `(box :layout 'MODE ...)`; core provides no layout-name aliases.
 
-### 2.5 Fragment
+### 2.5 Ebox DSL primitives and sugar
+
+ETAF View and Ebox DSL are different layers: ETAF has Text/Box/Fragment/Component,
+while Ebox receives lowered content and layout. The target Ebox DSL has one structural
+tag:
+
+```elisp
+(box :layout MODE ...)
+```
+
+An Ebox box may be a content leaf or own children and a layout context. A Range
+descriptor is an incremental backend protocol, not an authoring node. A bare string is
+content-literal shorthand, not a node type.
+
+Current tags classify as follows:
+
+| Current tag | Classification | Target expression |
+| --- | --- | --- |
+| `ebox` | compatibility alias for `box` | remove; use `box` |
+| `spacer` | empty-Box convenience sugar | remove; use a childless `box` |
+| `row` | layout-tag sugar | `(box :layout 'row ...)` |
+| `column` | layout-tag sugar | `(box :layout 'column ...)` |
+| `flex` | layout-tag sugar | `(box :layout 'flex ...)` |
+| `grid` | layout-tag sugar | `(box :layout 'grid ...)` |
+| `item` | Flex-child participation sugar | put flex/order/align-self properties on the child Box |
+| `grid-item` | Grid-child placement sugar | put grid placement properties on the child Box |
+
+Item wrappers are therefore unnecessary. Parent-participation properties belong to
+the child Box and are validated by the parent layout mode:
+
+```elisp
+(box :layout 'flex
+  (box :flex-grow 1 :content "A"))
+
+(box :layout 'grid
+  (box :grid-column '(1 :span 2) :content "Header"))
+```
+
+These are low-level Ebox examples, so Ebox `:content` is valid. ETAF View continues to
+use Text/children and does not expose `:content`.
+
+The target Ebox DSL retains none of those aliases or sugar tags. Ebox still implements
+the layout algorithms independently, but algorithm kinds are not authoring node kinds.
+
+### 2.6 Fragment
 
 Fragment is a nonvisual structural Range. It may contain zero, one, or many sibling
 Views, creates no Box or layout context, and may carry only a stable `:key` plus
@@ -101,7 +150,7 @@ children. Runtime may retain and replace its Range independently.
 A Component call has no fixed outer/layout properties. Its root Text/Box determines
 participation. A transparent Component returning a Fragment may have multiple roots.
 
-### 2.6 Strings, content, and empty Boxes
+### 2.7 Strings, content, and empty Boxes
 
 Strings under a Box normalize to Text, so `(box "text")` equals
 `(box (text "text"))`. ETAF does not expose `(box :content ...)`; `:content` remains an
@@ -269,6 +318,10 @@ Current code still registers `text`, `fragment`, `container`, `row`, `column`, `
 `:layout 'normal` are not implemented, and the target public View does not retain
 `raw-ebox`.
 
+Current Ebox DSL still accepts `box`, `ebox`, `row`, `column`, `flex`, `item`, `grid`,
+`grid-item`, and `spacer`. The target Ebox DSL keeps only `box`; all other tags are
+removed or represented as Box properties according to the table above.
+
 This is a clean redesign: old Host names and old `.etaf` sources need not continue to
 run, and no long-lived compatibility layer is added. Formal architecture/user docs must
 not present target syntax as delivered before implementation is complete.

docs/proposals/module-boundaries.zh.md

@@ -7,6 +7,10 @@
 本文只定义目标模型、模块 owner、依赖方向和完成条件。实现顺序属于单独的
 实施计划；历史名称和兼容策略不参与目标架构设计。
 
+用户心智成本是本提案的硬约束：同一能力只有一个规范名称和一种推荐写法；内部
+算法、后端节点、wrapper 和兼容别名不能作为并列公共概念。普通应用只需学习
+Text、Box、Component；Fragment、布局细节和底层包通过渐进披露进入。
+
 ## 1. 最终模型
 
 ETAF 的表示链只有四层：
@@ -117,7 +121,50 @@ run-in、list-item 或任意匿名盒规则。Ebox 可以把 `normal` 映射为
 (box :layout 'grid ...)
 ```
 
-### 2.5 Fragment
+### 2.5 Ebox DSL 的基础节点与语法糖
+
+ETAF View 和 Ebox DSL 是两层不同接口：ETAF 有 Text/Box/Fragment/Component；
+Ebox 只接收已经降低的内容与布局。目标 Ebox DSL 只有一个基础结构 tag：
+
+```elisp
+(box :layout MODE ...)
+```
+
+Ebox `box` 可以是 content leaf，也可以包含 children 并建立布局上下文。Range
+descriptor 是增量后端协议，不是作者 DSL 节点；裸字符串只是 content literal
+简写，也不是节点类型。
+
+当前 DSL 的其他 tag 必须明确分类，不能与基础节点并列：
+
+| 当前 tag | 分类 | 目标表达 |
+| --- | --- | --- |
+| `ebox` | `box` 的兼容别名 | 删除，统一写 `box` |
+| `spacer` | 空 Box 便捷糖 | 删除，使用无 children 的 `box` |
+| `row` | layout tag 糖 | `(box :layout 'row ...)` |
+| `column` | layout tag 糖 | `(box :layout 'column ...)` |
+| `flex` | layout tag 糖 | `(box :layout 'flex ...)` |
+| `grid` | layout tag 糖 | `(box :layout 'grid ...)` |
+| `item` | Flex child participation 糖 | 把 `:flex-*`、`:order`、`:align-self` 直接写在 child Box |
+| `grid-item` | Grid child placement 糖 | 把 `:grid-*` placement 直接写在 child Box |
+
+因此 `item` 和 `grid-item` 不是必要 wrapper。父级参与属性属于 child Box，并由
+父级 layout mode 验证：
+
+```elisp
+(box :layout 'flex
+  (box :flex-grow 1 :content "A"))
+
+(box :layout 'grid
+  (box :grid-column '(1 :span 2) :content "Header"))
+```
+
+以上示例是 Ebox 低层 DSL，因此可以使用 Ebox 的 `:content`；ETAF View 仍然只用
+Text/children，不暴露 `:content`。
+
+目标 Ebox DSL 不保留上述兼容别名或糖。布局算法仍由 Ebox 分别实现，但节点
+分类只保留 `box`；算法种类不等于作者节点种类。
+
+### 2.6 Fragment
 
 `Fragment` 是无视觉 wrapper 的结构 Range：
 
@@ -130,7 +177,7 @@ Component call 本身没有 `:outer` 或 `:layout`。它的根 Text/Box 决定
 布局；返回 Fragment 的透明 Component 可以产生多个兄弟节点，因此不存在单一的
 “Component 外部盒子”。
 
-### 2.6 字符串、content 与空 Box
+### 2.7 字符串、content 与空 Box
 
 Box 子节点中的字符串规范化为 Text：
 
@@ -336,6 +383,10 @@ Component identity、依赖所有权、TP 优先级和 generation authority 不
 `flex`、`grid` 和 `spacer`，并提供 `raw-ebox`；目标 `box`、`:outer`、
 `:layout 'normal` 尚未实现，目标公共 View 也不保留 `raw-ebox`。
 
+当前 Ebox DSL 仍接受 `box`、`ebox`、`row`、`column`、`flex`、`item`、`grid`、
+`grid-item` 和 `spacer`。目标 Ebox DSL 只保留 `box`；其他 tag 按上表删除或改为
+Box 属性。
+
 这是干净重设计，不要求旧 Host 名称或旧 `.etaf` 文件继续运行，也不增加长期
 兼容层。实现完成前，正式架构和用户指南不得把目标语法描述成当前 API。