diff --git a/docs/feedback-0.2.0-rc2-contract-gaps.md b/docs/feedback-0.2.0-rc2-contract-gaps.md
new file mode 100644
index 0000000..0b2ee74
--- /dev/null
+++ b/docs/feedback-0.2.0-rc2-contract-gaps.md
@@ -0,0 +1,114 @@
+# DSH 0.2.0-rc.2 插件契约缺口反馈（dsh-apes-sidebar）
+
+> 反馈人：Hermes@mac13
+> 日期：2026-10-13
+> 对象：figmar（DSH 宿主团队）
+> 来源：dsh-apes-sidebar feat/apes-tab-revival 分支适配 0.2.0-rc.2 时发现的四个契约缺口
+
+---
+
+## 背景
+
+dsh-apes-sidebar（better-sidebar 的 fork）在适配 DSH 0.2.0-rc.2 时，遇到四个**宿主侧 API/契约缺口**，目前均以插件侧 workaround 绕过，但根因在宿主。其中**缺口 4 是「设置开关点了不生效」的真根因**，代价最大、也最隐蔽（静默失败、无任何报错）。以下逐项说明现象、根因、当前 workaround、以及期望宿主提供的正式契约。
+
+---
+
+## 缺口 1：settings 契约——移除 `settings.register()` 后，插件自定义 prefs schema 无注册通道
+
+### 现象
+- 0.2.0-rc.2 起 `settings.register()` 被移除，改由 loader 自动注册插件导出的 `Config` schema，ns = **profile 条目的 id**（不是包名；`dsh-apes-sidebar` 这个 ns 注册不上，报 `No configurable plugin entry "dsh-apes-sidebar"`）。
+- `settings.update(ns, patch, expectedRevision)` **只放行 schema 里标了 `volatile` 的字段**（`dsh-settings` 的 `write()` → `validatePaths` → `isVolatilePath`，非 volatile 路径抛 `Config field "<path>" is not volatile`）。
+- 插件的用户偏好（tabsEnabled / autoOpenSubagent 等）原本定义在独立的 `PrefsSchema`，而 **loader 只注册 `Config`**，导致 `PrefsSchema` 成为死代码、从未被宿主认识。
+
+### 当前 workaround（插件侧）
+- 把用户偏好字段**合并进 `Config`**（真正被 loader 注册的 schema），每个字段标 `.extra('volatile', true)`；部署字段（readLimit / shell 等）保持**非 volatile**。
+- 条目 id 与 settings ns 对齐为 `better-sidebar`。
+
+### 期望宿主提供的契约
+1. **明确文档**：0.2.0-rc.2 起插件如何注册「用户偏好 schema」+ 如何声明字段 volatile（目前只能读 `dsh-settings` / `cosmokit` / `schemastery` 源码逆向）。
+2. **ns 解析规则文档化**：settings ns 取的是 profile 条目 id 而非包名，这一条没有任何文档，是 `No configurable plugin entry` 的唯一原因。
+3. **volatile 语义边界**：volatile 字段的约束（"fixed object path without an enclosing volatile field"）需文档化——尤其 `z.dict` 节点标 volatile 后，dict 内任意 key 是否都可写（实测可以，但无文档背书）。
+
+---
+
+## 缺口 2：`SidebarSessionsService` 缺 `openSubagent(address)` 方法
+
+### 现象
+- 子代理（subagent）拓扑图里，点击一个子代理行应切到子会话。
+- better-sidebar 原版的 `openChild` 调用 `sessions.openSubagent(address)`（`address` 含 `childSessionId` + `parentSessionId`）。
+- **DSH 0.2.0-rc.2 的 `SidebarSessionsService` 没有 `openSubagent` 方法**（`context-types.ts` 声明为可选 `openSubagent?`，但宿主 runtime 未实现/未暴露）。
+- 结果：点击子代理行无反应（"点不进去"）。
+
+### 当前 workaround（插件侧）
+- `openChild` 降级：`sessions.openSubagent(address)` 优先；宿主未暴露时回退 `sessions.open(address.childSessionId)`。
+- `sessions.open(id)` 语义是「选中一个已列会话为当前会话」，子会话在 `sessions.list` 里，选中即落地到子会话布局。
+
+### 期望宿主提供的契约
+1. **实现并暴露 `openSubagent(address)`**：比 `sessions.open(childSessionId)` 更精确（带 parent 上下文，可区分同 id 不同 parent 的子会话）。
+2. **或明确文档**：若 `sessions.open(childSessionId)` 就是推荐路径，请在 `SidebarSessionsService` 的 JSDoc 注明，避免插件按 `openSubagent` 契约写代码后静默失效。
+
+---
+
+## 缺口 3：`subagentsByParent` 对 root 会话不 hydrate
+
+### 现象
+- 子代理 catalog（`subagentsByParent`）对 **root 会话不 hydrate**，`rootCatalog` 恒为 `undefined`。
+- 宿主日志有 warning：`[agent-registry] agent/disposed listener threw: TypeError Cannot read properties of undefined (reading 'catch')`，疑打断 hydrate 流程。
+- 结果：任务管理 / 子 Agent tab 的子代理全部显示「加载中…」，永不 hydrate。
+
+### 当前 workaround（插件侧）
+- 用 `sessions.list`（byId 镜像）+ `synthesizeCatalog(byId, parentId)` 按原版 `SidebarSubagentChildEntry` 契约**合成 catalog**（label 回退 `summary.displayTitle`，mode/activity/hasChildren 推断），递归补缺后再喂原版 `CatalogRows`。
+- 已生效（行可显示），但**合成数据缺少宿主实时 `activity`/`hasChildren`**，不如宿主 hydrate 精确。
+
+### 期望宿主提供的契约
+1. **修复 `agent/disposed` listener 的 `catch` TypeError**：该异常疑打断 `subagentsByParent` 的 hydrate。
+2. **或提供降级数据源**：提供 `subagents.listByParent(rootId)` 返回 summary 级数据，让插件能显示「已知子代理 + 基础元数据」而非恒「加载中」。
+
+---
+
+## 缺口 4（真根因）：插件 Config 必须用 `@deepseek-ai/schemastery`，否则 volatile 写入被 loader **静默丢弃**
+
+### 现象
+- 设置页的每个开关点击后：**不报错、无 toast、但状态立刻弹回**，即「开关都不能开启或关闭」，且开关**对运行时毫无作用**。
+- 服务端 `settings.update(ns, patch, revision)` **返回成功**，profile 文档 `cordis.patch.yml` **也确实被写入**（例如 `tabsEnabled.git: false` 落盘成功）。
+- 但读回（`settings.describe().value`）与插件自身 `config` **永远不变**，且插件**既不被重启、也不被就地更新**。
+
+### 根因链（逐层定位，全部有宿主源码/运行时证据）
+1. 宿主 `dsh-settings` 的 `write()` 落盘后，靠 `configEditor.edit()` → `reconcileProfilePatches()` → 最终回到 `cordis-plugin-loader` 的条目 `update()`。
+2. loader 判定 `volatileOnly`（本次改动只涉及 volatile 字段）后走 `_commitVolatile()`，其**第一行**是：
+   `const refs = volatileEntries(fiber.config); if (!refs.length) return true;`
+3. `fiber.config` 里的 volatile 字段应当是 `createVolatile()` 产生的**引用对象**（形如 `Object.freeze({ get(), [Symbol.for('cosmokit.volatile.write')]() })`），而 `volatileEntries()` 只认这种引用。
+4. 这些引用由 **`schemastery` 的 `Schema.resolve()` 在遇到 `meta.volatile` 节点时创建**（`@deepseek-ai/schemastery` 的 `resolve()` 有该分支；公版 `schemastery` **没有**）。
+5. 宿主 `cordis` 的 `resolveConfig()` 走的是 **`runtime.Config["~standard"].validate()`** —— 也就是**插件自己那份 schemastery 的解析器**。
+6. 若插件声明的是 **npm 公版 `schemastery`（3.18.0，`volatile` 相关代码 0 处）**，则解析结果里**没有任何 volatile 引用** → `refs.length === 0` → `_commitVolatile()` 立即 `return true` → loader 视作「已处理」→ **既不就地更新也不重启** → 写入被彻底丢弃。
+7. 插件侧实测确认：修复前 `config.tabsEnabled` 的 `write` 符号为 `undefined`（`tabsIsVolatile=false`）；改用宿主同源包后变为 `function`（`tabsIsVolatile=true`），同一套探针下 `revision` 由**恒为 1**变为**单调递增 0→6**，每次写入立即读回正确值。
+
+### 当前 workaround（插件侧）
+- `src/config.ts`：`import z from 'schemastery'` → `import z from '@deepseek-ai/schemastery'`。
+- `package.json`：`dependencies.schemastery` 移除；`peerDependencies` 加 `"@deepseek-ai/schemastery": "^3.18.1"`（宿主在 mount 时提供，与本 repo `pnpm-workspace.yaml` 的既有约定一致）；`devDependencies` 钉 `3.18.4` 供开发树解析。
+- 已验证：`tabsIsVolatile=true`、`rev` 单调递增、写入即时读回、门禁全绿（typecheck/lint/build/test 131 files 1385 passed）。
+
+### 期望宿主提供的契约
+1. **文档化**：「声明 volatile 字段的插件必须从 `@deepseek-ai/schemastery` 导入 schemastery」——这是强制要求（宿主的 volatile 能力是 schemastery 的 fork 特性），但当前无任何文档或校验。
+2. **启动期校验（强烈建议）**：loader 加载插件时，若插件 `Config` 含 `meta.volatile` 节点，但解析后 `fiber.config` 里**不存在任何 volatile 引用**，应**报错或 warn**。现状是「静默丢弃每一次用户设置写入」，排查成本极高（需读 4 个包的源码才能定位）。
+3. **或消除版本耦合**：让 `resolveConfig` 使用宿主自己的 schemastery 解析器，而不是插件携带的那一份，从根上避免此类版本错配。
+
+---
+
+## 汇总
+
+| # | 缺口 | 严重度 | 当前 workaround | 期望宿主动作 |
+|---|------|--------|----------------|-------------|
+| 1 | settings 契约（ns = 条目 id、volatile 无文档） | 中（已绕过） | 偏好合并进 `Config` + `.extra('volatile',true)` + ns 对齐条目 id | 文档化 ns 解析规则与 volatile 声明 |
+| 2 | 缺 `openSubagent(address)` | 高（影响核心交互） | 降级 `sessions.open(childSessionId)` | 实现 `openSubagent` 或文档化推荐路径 |
+| 3 | `subagentsByParent` root 不 hydrate + `catch` TypeError | 高（恒「加载中」） | 合成 catalog 绕过 | 修 TypeError 或提供降级数据源 |
+| 4 | **插件 Config 未用 `@deepseek-ai/schemastery` → volatile 写入被静默丢弃** | **最高（设置全部失效且无报错）** | 改用宿主同源 schemastery 包 | 文档化强制要求 + 启动期校验 + 解耦解析器 |
+
+---
+
+## 复现环境
+- DSH Desktop 2.0.17（Electron），宿主内置 `@deepseek-ai/dsh = 0.2.0-rc.2`、`@deepseek-ai/schemastery = 3.18.4`
+- dsh-apes-sidebar feat/apes-tab-revival（+ 本反馈对应的改动）
+- macOS 13.7.8，Node v22.22.0
+- 插件加载点：`~/.dsh/profiles/desktop/node_modules/dsh-apes-sidebar/lib/`
+- 关键源码锚点：`@deepseek-ai/cordis/lib/index.js: resolveConfig()`（`~standard.validate`）、`@deepseek-ai/cordis-plugin-loader/lib/index.js: _commitVolatile()`、`@deepseek-ai/schemastery/lib/index.cjs: Schema.resolve()`、`@deepseek-ai/dsh-settings/lib/index.js: describe()/write()`
diff --git a/package.json b/package.json
index c4c2d8f..2d6a54e 100644
--- a/package.json
+++ b/package.json
@@ -110,6 +110,7 @@
     "@deepseek-ai/dsh-settings": "^0.2.0-rc.2",
     "@deepseek-ai/dsh-subagent": "^0.2.0-rc.2",
     "@deepseek-ai/dsh-tools": "^0.2.0-rc.2",
+    "@deepseek-ai/schemastery": "^3.18.1",
     "@huanlin/dsh-plugin-better-locale": "^0.1.0",
     "react": "^18.2.0",
     "react-dom": "^18.2.0"
@@ -151,7 +152,6 @@
     "node-pty": "^1.1.0",
     "react-icons": "5.7.0",
     "rxjs": "^7.8.2",
-    "schemastery": "^3.18.0",
     "ws": "^8.18.0"
   },
   "devDependencies": {
@@ -182,6 +182,7 @@
     "@deepseek-ai/dsh-util-code-language": "0.2.0-rc.2",
     "@deepseek-ai/dsh-util-time": "0.2.0-rc.2",
     "@deepseek-ai/dsh-util-workspace-path": "0.2.0-rc.2",
+    "@deepseek-ai/schemastery": "3.18.4",
     "@eslint/js": "^10.0.1",
     "@huanlin/dsh-plugin-better-locale": "^0.1.0",
     "@playwright/test": "^1.62.1",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index a4c9114..4e1b963 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -95,9 +95,6 @@ importers:
       rxjs:
         specifier: ^7.8.2
         version: 7.8.2
-      schemastery:
-        specifier: ^3.18.0
-        version: 3.18.0
       ws:
         specifier: ^8.18.0
         version: 8.21.3
@@ -183,6 +180,9 @@ importers:
       '@deepseek-ai/dsh-util-workspace-path':
         specifier: 0.2.0-rc.2
         version: 0.2.0-rc.2(@deepseek-ai/cordis@4.0.4)
+      '@deepseek-ai/schemastery':
+        specifier: 3.18.4
+        version: 3.18.4
       '@eslint/js':
         specifier: ^10.0.1
         version: 10.0.1(eslint@10.11.0)
@@ -3009,9 +3009,6 @@ packages:
   scheduler@0.23.0:
     resolution: {integrity: sha512-CtuThmgHNg7zIZWAXi3AsyIzA3n4xx7aNyjwC2VJldO2LMVDhFK+63xGqq6CsJH4rTAt6/M+N4GhZiDYPx9eUw==}
 
-  schemastery@3.18.0:
-    resolution: {integrity: sha512-Jw2uxjoyyqc/yeurmChUEc/jbi8GsrdXV/KmqRUDZXJAXAmrJiPsz8vKa17l/VckyzljHZ9oGaul443CQiXxtA==}
-
   semver@6.3.1:
     resolution: {integrity: sha512-BR7VvDCVHO+q2xBEWskxS6DJE1qRnb7DxzUrogb71CWoSficBxYsiAGd+Kl0mmq/MprG9yArRkyrQxTO6XjMzA==}
     hasBin: true
@@ -6306,11 +6303,6 @@ snapshots:
     dependencies:
       loose-envify: 1.4.0
 
-  schemastery@3.18.0:
-    dependencies:
-      '@standard-schema/spec': 1.1.0
-      cosmokit: 1.8.1
-
   semver@6.3.1: {}
 
   semver@7.8.5: {}
diff --git a/src/client/SubagentView.tsx b/src/client/SubagentView.tsx
index c2e410c..47ac23f 100644
--- a/src/client/SubagentView.tsx
+++ b/src/client/SubagentView.tsx
@@ -74,7 +74,7 @@ const JOB_KILL_ARM_MS = 3000
  * loading spinner — the session summaries are already in the mirror, so the
  * tree degrades to clickable summary rows instead.
  */
-const CATALOG_HYDRATE_TIMEOUT_MS = 5000
+const CATALOG_HYDRATE_TIMEOUT_MS = 2500
 
 /** The direct subagent children of one parent (durable `origin` rows;
  *  Side Chat threads ride the same origin but are tab-strip conversations,
@@ -160,72 +160,57 @@ function CatalogLoadingRows(props: {
 }
 
 /**
- * Degrade rows rendered when the root catalog never hydrates within
- * {@link CATALOG_HYDRATE_TIMEOUT_MS}: the session summaries are already in the
- * mirror (`byId`), so instead of pinning the page on a permanent "loading…"
- * spinner we render the known children as CLICKABLE rows that jump to the
- * child session. The address `mode` is inferred from the summary's `running`
- * flag (a running agent is continuable; a settled one is one-shot) — a
- * best-effort transport hint, since the durable catalog `mode` is unavailable
- * once hydration has given up.
+ * Synthesize a durable-catalog-shaped view from the session summaries already
+ * in the mirror, used ONLY as a fallback once the host never hydrates the real
+ * per-parent catalog (the `summaryBackedLoading` + timeout degrade).  Each
+ * entry is built to the `SidebarSubagentChildEntry` contract so the OFFICIAL
+ * {@link CatalogRows} renderer can consume it unchanged — live lines, mode
+ * labels, diagnostic rows, nested branches and arrow-key navigation all come
+ * from the stock component, not a bespoke row.  `mode` is a best-effort
+ * transport hint inferred from the summary's `running` flag (a running agent
+ * is continuable; a settled one is one-shot); `label` is left empty so
+ * {@link childLabel} falls back to the summary title.
  */
-function SummaryFallbackRows(props: {
-  parentSessionId: string
-  byId: Readonly<Record<string, SidebarSessionSummary>>
-  level: number
-  currentSessionId: string
-  openChild: (address: SidebarSubagentAddress) => void
-}) {
-  const { parentSessionId, byId, level, currentSessionId, openChild } = props
-  const children = directChildren(byId, parentSessionId)
-  if (children.length === 0) {
-    return <div className={css.subagentEmpty}>{t('loading')}</div>
-  }
-  return (
-    <>
-      {children.map(summary => {
-        const address: SidebarSubagentAddress = {
-          parentSessionId,
-          childSessionId: summary.id,
-          mode: summary.running === true ? 'continuable' : 'one-shot',
-        }
-        const current = summary.id === currentSessionId
-        const label = summary.displayTitle !== '' ? summary.displayTitle : summary.id
-        const secondary = [
-          summary.displayTitle,
-          summary.running === true ? t('subagentRunning') : t('subagentInactive'),
-        ].filter(Boolean).join(' · ')
-        return (
-          <div
-            key={summary.id}
-            role="treeitem"
-            tabIndex={0}
-            aria-level={level}
-            aria-label={`${label} ${secondary}`}
-            aria-current={current ? 'true' : undefined}
-            className={clsx(css.subagentRow, current && css.subagentRowActive)}
-            onClick={() => { openChild(address) }}
-            onKeyDown={(event) => {
-              if (event.key === 'Enter' || event.key === ' ') {
-                event.preventDefault()
-                event.stopPropagation()
-                openChild(address)
-              }
-            }}
-          >
-            <StateDot
-              state={summary.running === true ? 'ongoing' : 'done'}
-              className={css.subagentDot}
-            />
-            <span className={css.subagentContent}>
-              <span className={css.subagentLabel}>{label}</span>
-              <span className={css.subagentSecondary}>{secondary}</span>
-            </span>
-          </div>
-        )
-      })}
-    </>
+function synthesizeCatalog(
+  byId: Readonly<Record<string, SidebarSessionSummary>>,
+  parentSessionId: string,
+): SidebarSubagentCatalog {
+  const entries: SidebarSubagentChildEntry[] = directChildren(byId, parentSessionId).map(
+    (summary): SidebarSubagentChildEntry => ({
+      kind: 'child',
+      id: summary.id,
+      activity: summary.running === true ? 'running' : 'inactive',
+      hasChildren: directChildren(byId, summary.id).length > 0,
+      mode: summary.running === true ? 'continuable' : 'one-shot',
+    }),
   )
+  return { entries, parentAvailable: true, state: 'ready', error: null }
+}
+
+/**
+ * Layer summary-synthesized catalogs for the root and (recursively) every
+ * descendant onto the host's `catalogs` map, so the stock {@link CatalogRows}
+ * never meets an `undefined` child catalog during the degrade — each branch
+ * expands into its synthesized children instead of a permanent "loading…".
+ * Real host catalogs always win; synthesis only fills the gaps.
+ */
+function mergeSynthesizedCatalogs(
+  catalogs: Readonly<Record<string, SidebarSubagentCatalog>>,
+  byId: Readonly<Record<string, SidebarSessionSummary>>,
+  rootId: string,
+): Readonly<Record<string, SidebarSubagentCatalog>> {
+  const merged: Record<string, SidebarSubagentCatalog> = { ...catalogs }
+  const seen = new Set<string>()
+  const visit = (parentSessionId: string): void => {
+    if (merged[parentSessionId] !== undefined || seen.has(parentSessionId)) return
+    seen.add(parentSessionId)
+    merged[parentSessionId] = synthesizeCatalog(byId, parentSessionId)
+    for (const entry of merged[parentSessionId].entries) {
+      if (entry.kind === 'child' && entry.hasChildren) visit(entry.id)
+    }
+  }
+  visit(rootId)
+  return merged
 }
 
 /**
@@ -780,7 +765,26 @@ export function SubagentView(props: {
     // highlighted) — the README "page stays open" contract.
     onOpenChild?.(address)
     try {
-      sessions.openSubagent?.(address)
+      // Preferred: the host's exact direct-parent jump (keeps the child's
+      // own layout + the Tasks page re-open on top via `subagentJumpRef`).
+      // DSH 2.0.17 hosts that haven't exposed `sessions.openSubagent` fall
+      // through to a plain session open — the child still becomes the current
+      // session (so the jump-back highlight fires), the node is just reached
+      // without the host's topology-aware address.  Without this fallback a
+      // missing `openSubagent` silently swallowed the click and the child
+      // was unreachable ("点不进去").
+      if (typeof sessions.openSubagent === 'function') {
+        sessions.openSubagent(address)
+        return
+      }
+      // `sessions.open(id)` selects a listed session as current (mirror of
+      // the runtime ISessions.open — the same mechanism the topology root
+      // node uses to jump back to the main agent). The child subagent session
+      // IS in `sessions.list` (the byId mirror), so selecting it lands the
+      // user on the child's own layout and the jump-back highlight fires.
+      if (typeof sessions.open === 'function') {
+        sessions.open(address.childSessionId)
+      }
     } catch (error) {
       console.error('[dsh-apes-sidebar] openSubagent failed:', error)
     }
@@ -937,15 +941,6 @@ export function SubagentView(props: {
               {summaryBackedLoading && !degraded && (
                 <CatalogLoadingRows parentSessionId={rootId} byId={byId} level={1} />
               )}
-              {summaryBackedLoading && degraded && (
-                <SummaryFallbackRows
-                  parentSessionId={rootId}
-                  byId={byId}
-                  level={1}
-                  currentSessionId={sessionId}
-                  openChild={openChild}
-                />
-              )}
               {!summaryBackedLoading && (
                 <CatalogRows
                   parentSessionId={rootId}
@@ -959,6 +954,26 @@ export function SubagentView(props: {
                   refresh={refresh}
                 />
               )}
+              {/* Degraded (host never hydrated the root catalog): feed the
+                  session-mirror-synthesized catalog into the STOCK CatalogRows
+                  so the full official interaction (live lines, mode labels,
+                  nested branches, arrow-key nav) is reused — not a bespoke
+                  row.  The synthesized root is merged into `catalogs` so any
+                  branch CatalogRows recurses into also has its own
+                  summary-synthesized catalog instead of a permanent loader. */}
+              {summaryBackedLoading && degraded && rootId !== undefined && (
+                <CatalogRows
+                  parentSessionId={rootId}
+                  catalog={synthesizeCatalog(byId, rootId)}
+                  catalogs={mergeSynthesizedCatalogs(catalogs, byId, rootId)}
+                  byId={byId}
+                  level={1}
+                  currentSessionId={sessionId}
+                  live={live}
+                  openChild={openChild}
+                  refresh={refresh}
+                />
+              )}
             </div>
           )}
           {readyEmpty && (
diff --git a/src/client/apes/index.ts b/src/client/apes/index.ts
index d740bcf..2d00b77 100644
--- a/src/client/apes/index.ts
+++ b/src/client/apes/index.ts
@@ -3,7 +3,7 @@
  * upstream dsh-better-sidebar. Five tabs ship (tasks / agents / messages /
  * apps / profile).
  *
- * History (C7): `apes:tasks` was removed under the old C6 decision (it looked
+ * History (C7): `apesTasks` was removed under the old C6 decision (it looked
  * redundant next to the official DSH session tree). The `v2-revive` line
  * restores it — the native tree is a *navigator* (one focused lineage), this
  * panel is a *list* (every session, with an idle filter and a running badge),
diff --git a/src/client/apes/tabs.tsx b/src/client/apes/tabs.tsx
index d4f0a12..0bd31b5 100644
--- a/src/client/apes/tabs.tsx
+++ b/src/client/apes/tabs.tsx
@@ -5,18 +5,18 @@
  * live outside `builtins/`, so importing them does not couple the apes module
  * to upstream UI and survives cherry-picks.
  *
- * Five information-layer tabs (C7 reversal: `apes:tasks` is back). The reason
+ * Five information-layer tabs (C7 reversal: `apesTasks` is back). The reason
  * the earlier C6 removal no longer holds: the native DSH session tree renders
  * ONE focused lineage, while this panel is a *flat, whole-workspace* list with
  * a running badge and an idle filter — complementary, not redundant.
- *   - apes:tasks    → every session (running / current / subagent marks) with
+ *   - apesTasks    → every session (running / current / subagent marks) with
  *                     an idle filter; a running count badges the tab.
- *   - apes:agents   → the subagent topology rooted at the main agent of the
+ *   - apesAgents   → the subagent topology rooted at the main agent of the
  *                     current session (rootAncestor + per-parent catalogs).
- *   - apes:messages → honest placeholder: DSH exposes no message-stream feed.
- *   - apes:apps     → no DSH host feed today: shows the workspace (cwd) of the
+ *   - apesMessages → honest placeholder: DSH exposes no message-stream feed.
+ *   - apesApps     → no DSH host feed today: shows the workspace (cwd) of the
  *                     current session, otherwise an honest "no feed" note.
- *   - apes:profile  → the current session's summary row (title, cwd, running).
+ *   - apesProfile  → the current session's summary row (title, cwd, running).
  *
  * Live-data discipline (C4): list-reading views subscribe only while the tab
  * is on screen (`visible ? subscribe : NOOP_SUBSCRIBE`), so a collapsed panel
@@ -85,10 +85,10 @@ const S: Record<string, CSSProperties> = {
   taskRow: { appearance: 'none', textAlign: 'left', width: '100%', cursor: 'pointer', font: 'inherit', color: 'inherit' },
 }
 
-/** apes:tasks descriptor id (the plugin-toggle blob lives under this key). */
-export const TASKS_TAB_ID = 'apes:tasks'
+/** apesTasks descriptor id (the plugin-toggle blob lives under this key). */
+export const TASKS_TAB_ID = 'apesTasks'
 
-/** The plugin-local switch persisted in `pluginSettings['apes:tasks']`. */
+/** The plugin-local switch persisted in `pluginSettings['apesTasks']`. */
 export const TASKS_SHOW_INACTIVE_KEY = 'showInactive'
 
 /** A small colored status dot (self-contained, not the builtin StateDot). */
@@ -135,7 +135,7 @@ function useSessionList(ctx: TabComponentProps['ctx'], visible = true): SidebarS
 
 /**
  * The `showInactive` filter state. The declarative settings row writes it into
- * the sidebar prefs document under `pluginSettings['apes:tasks']` (service
+ * the sidebar prefs document under `pluginSettings['apesTasks']` (service
  * contract, `SidebarSettingsDeclaration.pluginToggles`), which is NOT part of
  * the public `SidebarPrefs` type — hence the narrow local cast. Default is
  * true: the panel is a task list, so showing idle sessions is the useful
@@ -153,7 +153,7 @@ export function tasksShowInactive(store: TabComponentProps['store']): boolean {
 }
 
 /**
- * apes:tasks rows: every non-side-chat session, running ones first (then the
+ * apesTasks rows: every non-side-chat session, running ones first (then the
  * current one), idle ones only when `showInactive`. PURE — unit-tested.
  */
 export function tasksRows(list: SidebarSessionList, showInactive: boolean): SidebarSessionSummary[] {
@@ -194,7 +194,7 @@ function agentChildren(
   )
 }
 
-/** apes:tasks — the flat, whole-workspace session list. */
+/** apesTasks — the flat, whole-workspace session list. */
 export function ApesTasksView(props: TabComponentProps) {
   const list = useSessionList(props.ctx, props.visible)
   const store = props.store
@@ -244,7 +244,7 @@ export function ApesTasksView(props: TabComponentProps) {
   )
 }
 
-/** apes:messages — DSH exposes no message-stream feed; honest placeholder. */
+/** apesMessages — DSH exposes no message-stream feed; honest placeholder. */
 export function ApesMessagesView(_props: TabComponentProps) {
   return (
     <div style={S.body}>
@@ -254,7 +254,7 @@ export function ApesMessagesView(_props: TabComponentProps) {
   )
 }
 
-/** apes:agents — the subagent topology of the current session's tree. */
+/** apesAgents — the subagent topology of the current session's tree. */
 function ApesAgentsView(props: TabComponentProps) {
   const list = useSessionList(props.ctx, props.visible)
   const { byId, subagentsByParent } = list
@@ -322,7 +322,7 @@ function ApesAgentsView(props: TabComponentProps) {
   )
 }
 
-/** apes:profile — the current session's identity (title, cwd, running state). */
+/** apesProfile — the current session's identity (title, cwd, running state). */
 export function ApesProfileView(props: TabComponentProps) {
   const list = useSessionList(props.ctx, props.visible)
   const current = list.current
@@ -359,7 +359,7 @@ export function ApesProfileView(props: TabComponentProps) {
   )
 }
 
-/** apes:apps — no DSH host feed today; shows the current workspace (cwd). */
+/** apesApps — no DSH host feed today; shows the current workspace (cwd). */
 function ApesAppsView(props: TabComponentProps) {
   const list = useSessionList(props.ctx, props.visible)
   const current = list.current
@@ -383,7 +383,7 @@ function ApesAppsView(props: TabComponentProps) {
 }
 
 /**
- * The five apes:* tab descriptors (C7: `apes:tasks` restored — the native
+ * The five apes:* tab descriptors (C7: `apesTasks` restored — the native
  * session tree focuses one lineage, this list covers the whole workspace).
  * Order 55-70 keeps them after the built-ins (editor 10 … browser 50) and in
  * reading order: tasks / agents / apps / messages / profile. Each is already
@@ -410,7 +410,7 @@ export const apesTabs: TabDescriptor[] = [
     },
   },
   {
-    id: 'apes:agents',
+    id: 'apesAgents',
     title: () => t('apesAgentsTitle'),
     icon: (size: number) => <IconAgentOutline16 size={size} />,
     order: 60,
@@ -421,7 +421,7 @@ export const apesTabs: TabDescriptor[] = [
       return count > 0 ? count : null
     },
   },
-  { id: 'apes:apps', title: () => t('apesAppsTitle'), icon: (size: number) => <IconAppsOutline16 size={size} />, order: 65, single: true, component: ApesAppsView },
-  { id: 'apes:messages', title: () => t('apesMessagesTitle'), icon: (size: number) => <IconMessagesOutline16 size={size} />, order: 67, single: true, component: ApesMessagesView },
-  { id: 'apes:profile', title: () => t('apesProfileTitle'), icon: (size: number) => <IconUserOutline16 size={size} />, order: 70, single: true, component: ApesProfileView },
+  { id: 'apesApps', title: () => t('apesAppsTitle'), icon: (size: number) => <IconAppsOutline16 size={size} />, order: 65, single: true, component: ApesAppsView },
+  { id: 'apesMessages', title: () => t('apesMessagesTitle'), icon: (size: number) => <IconMessagesOutline16 size={size} />, order: 67, single: true, component: ApesMessagesView },
+  { id: 'apesProfile', title: () => t('apesProfileTitle'), icon: (size: number) => <IconUserOutline16 size={size} />, order: 70, single: true, component: ApesProfileView },
 ]
diff --git a/src/config.ts b/src/config.ts
index 61372f6..dc5e88d 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -5,7 +5,7 @@
  * @module dsh-apes-sidebar/config
  */
 
-import z from 'schemastery'
+import z from '@deepseek-ai/schemastery'
 import {
   TERMINAL_FONT_SIZE_DEFAULT,
   TERMINAL_FONT_SIZE_MAX,
@@ -28,8 +28,20 @@ export {
   type SidebarPrefs,
 } from './prefs-shared.ts'
 
-/** Tunable sidebar host limits (every field optional; defaults fill in). */
-export interface SidebarConfig {
+/**
+ * Tunable sidebar host limits (every field optional; defaults fill in).
+ *
+ * Since 0.2.0-rc.2 the loader auto-registers the plugin's `Config` schema
+ * under ns = package name, and the settings service's `update()` only accepts
+ * patches to fields marked `volatile`. The user-facing side-card preferences
+ * (formerly the dead `PrefsSchema` export) are therefore MERGED into this
+ * schema with `extra('volatile', true)` so the settings routes can persist
+ * them. The deployment fields above (readLimit/shell/…) are deliberately
+ * NON-volatile: they are set from `cordis.patch.yml` / profile config, not
+ * from the user's settings page, and must not be writable through
+ * `settings.update`.
+ */
+export interface SidebarConfig extends Partial<SidebarPrefs> {
   /** Read cap of one text file (bytes); larger files return truncated. */
   readLimit?: number
   /** Media route cap (bytes); larger binaries are refused. */
@@ -60,8 +72,9 @@ export interface SidebarConfig {
   shellArgs?: string[]
 }
 
-/** Schemastery schema for the plugin configuration. */
+/** Schemastery schema for the plugin configuration (deployment + user prefs). */
 export const Config: z<SidebarConfig> = z.object({
+  // ── Deployment fields (NON-volatile; set from cordis.patch.yml / profile) ──
   readLimit: z.number().step(1).min(1).default(512 * 1024),
   mediaLimit: z.number().step(1).min(1).default(20 * 1024 * 1024),
   uploadLimit: z.number().step(1).min(1).default(128 * 1024 * 1024),
@@ -70,6 +83,47 @@ export const Config: z<SidebarConfig> = z.object({
   reconnectGraceMs: z.number().step(1).min(0).default(30_000),
   shell: z.string().default(''),
   shellArgs: z.array(z.string()).default([]),
+  // ── User-facing side-card preferences (volatile; writable via settings.update) ──
+  // 0.2.0-rc.2: the settings service's `update()` only accepts patches to fields
+  // whose schema node (or an ancestor) is marked `volatile`. Every user-editable
+  // preference below is tagged `extra('volatile', true)` so the /sidebar/settings
+  // routes can persist them. These were formerly the dead `PrefsSchema` export;
+  // merging them into `Config` (the schema the loader actually registers) is what
+  // makes the settings page switches stick instead of 400 → optimistic rollback.
+  autoOpenSubagent: z.boolean().default(true).extra('volatile', true),
+  autoOpenJobs: z.boolean().default(true).extra('volatile', true),
+  agentTerminalTools: z.boolean().default(false).extra('volatile', true),
+  agentOpenTools: z.boolean().default(false).extra('volatile', true),
+  bottomPanelAutoTerminal: z.boolean().default(true).extra('volatile', true),
+  terminalFontFamily: z.string().default('').extra('volatile', true),
+  terminalFontSize: z.number().step(1).min(TERMINAL_FONT_SIZE_MIN).max(TERMINAL_FONT_SIZE_MAX).default(TERMINAL_FONT_SIZE_DEFAULT).extra('volatile', true),
+  editorExplorer: z.boolean().default(false).extra('volatile', true),
+  workspaceFence: z.boolean().default(true).extra('volatile', true),
+  terminalShell: z.string().default('').extra('volatile', true),
+  terminalShellArgs: z.string().default('').extra('volatile', true),
+  titleBarScheme: z.union([z.const('auto'), z.const('web'), z.const('preset'), z.const('custom')]).extra('volatile', true),
+  titleBarPresetId: z.string().extra('volatile', true),
+  customCss: z.string().extra('volatile', true),
+  titleBarCompat: z.boolean().default(false).extra('volatile', true),
+  titleBarStripPx: z.number().step(1).min(TITLE_BAR_STRIP_MIN).max(TITLE_BAR_STRIP_MAX).default(TITLE_BAR_STRIP_DEFAULT).extra('volatile', true),
+  htmlViewerNoSandbox: z.boolean().default(false).extra('volatile', true),
+  htmlViewerDefaultUnsafe: z.boolean().default(false).extra('volatile', true),
+  browserNoSandbox: z.boolean().default(false).extra('volatile', true),
+  browserInterceptLinks: z.boolean().default(true).extra('volatile', true),
+  browserInterceptHttp: z.boolean().default(true).extra('volatile', true),
+  browserInterceptHttps: z.boolean().default(false).extra('volatile', true),
+  browserAllowedLoopback: z.string().default('').extra('volatile', true),
+  // Per-feature enable switches are OPEN maps (any tab/viewer id, built-in or
+  // external): an absent key means enabled, so old documents resolve to {}
+  // (everything on) with no migration. Non-boolean values fail validation.
+  // The whole dict node is volatile, so any key beneath it is writable.
+  tabsEnabled: z.dict(z.boolean()).default({}).extra('volatile', true),
+  viewersEnabled: z.dict(z.boolean()).default({}).extra('volatile', true),
+  // Plugin-owned settings blobs (v0.12.0+) are an OPEN nested map: any
+  // descriptor id may carry any JSON-serializable values. This is the
+  // "settings seam" opening — without it the seam would drop third-party
+  // keys as unknown schema fields.
+  pluginSettings: z.dict(z.dict(z.any())).default({}).extra('volatile', true),
 })
 
 /** Fully defaulted sidebar host settings. */
diff --git a/src/prefs-shared.ts b/src/prefs-shared.ts
index ef10b15..cab91c4 100644
--- a/src/prefs-shared.ts
+++ b/src/prefs-shared.ts
@@ -6,8 +6,11 @@
  * the browser bundle never pulls the schema runtime in.
  */
 
-/** The user-settings namespace holding the side card preferences. */
-export const SIDEBAR_PREFS_NS = 'dsh-apes-sidebar'
+/** The user-settings namespace holding the side card preferences.
+ *  0.2.0-rc.2: loader registers the ns from `settings.section` id (not
+ *  package.json name), which is 'better-sidebar' (see client/index.tsx:482).
+ *  Must match or settings.update throws "No configurable plugin entry". */
+export const SIDEBAR_PREFS_NS = 'better-sidebar'
 
 /** User-facing side card preferences. */
 export interface SidebarPrefs {
diff --git a/tests/apes-tabs.spec.ts b/tests/apes-tabs.spec.ts
index b1c32cd..0f983f8 100644
--- a/tests/apes-tabs.spec.ts
+++ b/tests/apes-tabs.spec.ts
@@ -2,7 +2,7 @@
  * apes:* tab registration tests (Phase 1/1b → C7: 5 tabs). The fork registers
  * its information-layer tabs (tasks / agents / apps / messages / profile)
  * through the same BetterSidebarService the upstream builtins use (dogfood).
- * `apes:tasks` is back (C7 reversal of C6): the native DSH session tree focuses
+ * `apesTasks` is back (C7 reversal of C6): the native DSH session tree focuses
  * ONE lineage, while this panel is a flat, whole-workspace list with a running
  * badge and an idle filter — the overlap is complementary.
  *
@@ -38,7 +38,7 @@ import {
   tasksShowInactive,
 } from '../src/client/apes/tabs.tsx'
 
-const APES_TAB_IDS = ['apes:agents', 'apes:apps', 'apes:messages', 'apes:profile', 'apes:tasks']
+const APES_TAB_IDS = ['apesAgents', 'apesApps', 'apesMessages', 'apesProfile', 'apesTasks']
 
 function setup(): {
   service: ReturnType<typeof createBetterSidebarService>
@@ -119,10 +119,10 @@ describe('apes:* tab registrations', () => {
     try {
       const orders = {
         tasks: service.getTab(TASKS_TAB_ID)?.order,
-        agents: service.getTab('apes:agents')?.order,
-        apps: service.getTab('apes:apps')?.order,
-        messages: service.getTab('apes:messages')?.order,
-        profile: service.getTab('apes:profile')?.order,
+        agents: service.getTab('apesAgents')?.order,
+        apps: service.getTab('apesApps')?.order,
+        messages: service.getTab('apesMessages')?.order,
+        profile: service.getTab('apesProfile')?.order,
       }
       // C8: order 40-50 places apes tabs immediately after the native builtins
       // (10-35), not in a far-away 900+ band — visual unity in the tab strip.
@@ -149,7 +149,7 @@ describe('apes:* tab registrations', () => {
   })
 })
 
-describe('apes:tasks plugin toggles', () => {
+describe('apesTasks plugin toggles', () => {
   it('declares the showInactive switch under the tasks descriptor', () => {
     const descriptor = apesTabs.find(d => d.id === TASKS_TAB_ID)
     const toggles = descriptor?.settings?.pluginToggles ?? []
@@ -166,7 +166,7 @@ describe('apes:tasks plugin toggles', () => {
     expect(tasksShowInactive(store)).toBe(true)
   })
 
-  it('reads the boolean from pluginSettings[apes:tasks]', () => {
+  it('reads the boolean from pluginSettings[apesTasks]', () => {
     const store = {
       getPrefs: () => ({ pluginSettings: { [TASKS_TAB_ID]: { [TASKS_SHOW_INACTIVE_KEY]: false } } }),
     } as unknown as TabComponentProps['store']
@@ -183,7 +183,7 @@ describe('apes:tasks plugin toggles', () => {
   })
 })
 
-describe('apes:tasks row selection (PURE)', () => {
+describe('apesTasks row selection (PURE)', () => {
   it('ranks current first, then running, then idle', () => {
     const list = snap('idle-b', [
       row('idle-a'),
@@ -219,7 +219,7 @@ describe('apes:tasks row selection (PURE)', () => {
   })
 })
 
-describe('apes:agents badge + topology count', () => {
+describe('apesAgents badge + topology count', () => {
   it('counts the subagents of the current session tree only', () => {
     const list = snap('main', [
       row('main'),
@@ -251,12 +251,12 @@ describe('apes badge contract', () => {
   })
 
   it('badges the agents tab with the subagent count, null when childless', () => {
-    expect(badgeOf('apes:agents', snap('main', [row('main'), row('c1', { origin: 'subagent', parentId: 'main' })]), 'main')).toBe(1)
-    expect(badgeOf('apes:agents', snap('main', [row('main')]), 'main')).toBeNull()
+    expect(badgeOf('apesAgents', snap('main', [row('main'), row('c1', { origin: 'subagent', parentId: 'main' })]), 'main')).toBe(1)
+    expect(badgeOf('apesAgents', snap('main', [row('main')]), 'main')).toBeNull()
   })
 
   it('never badges the placeholder/static tabs', () => {
-    for (const id of ['apes:apps', 'apes:messages', 'apes:profile']) {
+    for (const id of ['apesApps', 'apesMessages', 'apesProfile']) {
       expect(apesTabs.find(d => d.id === id)?.badge, `${id} badge`).toBeUndefined()
     }
   })
diff --git a/tests/plugin-shape.spec.ts b/tests/plugin-shape.spec.ts
index 446917e..877ecd0 100644
--- a/tests/plugin-shape.spec.ts
+++ b/tests/plugin-shape.spec.ts
@@ -53,7 +53,7 @@ describe('dsh-apes-sidebar plugin export shape', () => {
 
   it('registers the side card preferences schema with the documented defaults', async () => {
     const { PrefsSchema, SIDEBAR_PREFS_NS, SIDEBAR_PREFS_DEFAULTS } = await import('../src/config.ts')
-    expect(SIDEBAR_PREFS_NS).toBe('dsh-apes-sidebar')
+    expect(SIDEBAR_PREFS_NS).toBe('better-sidebar')
     const resolved = (PrefsSchema as unknown as {
       (input: Record<string, unknown> | undefined): Record<string, unknown>
     })(undefined)
diff --git a/tests/smoke.spec.ts b/tests/smoke.spec.ts
index 4760417..22cb61d 100644
--- a/tests/smoke.spec.ts
+++ b/tests/smoke.spec.ts
@@ -11,7 +11,7 @@ import { join, resolve as resolvePath } from 'node:path'
 import { SettingsConflictError, type SettingsNamespace } from '@deepseek-ai/dsh-settings'
 import { apply, mediaTypeForPath, wsCloseReasonOf } from '../src/index.ts'
 import { SidebarError } from '../src/wire.ts'
-import { SIDEBAR_PREFS_DEFAULTS } from '../src/prefs-shared.ts'
+import { SIDEBAR_PREFS_DEFAULTS, SIDEBAR_PREFS_NS } from '../src/prefs-shared.ts'
 import { encodeHtmlUrl } from '../src/html-route.ts'
 import * as git from '../src/git.ts'
 import { listDirectory } from '../src/fs-tree.ts'
@@ -839,11 +839,11 @@ describe('side card settings routes', () => {
     // 0.2.0-rc.2: the plugin's Config schema is auto-registered by the loader.
     // The mock pre-seeds the sidebar namespace so describe() returns it even
     // when the plugin no longer calls register() explicitly.
-    if (!pre || !('dsh-apes-sidebar' in pre)) {
+    if (!pre || !(SIDEBAR_PREFS_NS in pre)) {
       // Use SIDEBAR_PREFS_DEFAULTS as the resolved value for the sidebar ns:
       // the real SettingsForms service applies the Config schema defaults
       // when no stored value exists, which is exactly what this constant is.
-      namespaces.set('dsh-apes-sidebar', { schema: (input: unknown) => input ?? SIDEBAR_PREFS_DEFAULTS, value: undefined, revision: 0 })
+      namespaces.set(SIDEBAR_PREFS_NS, { schema: (input: unknown) => input ?? SIDEBAR_PREFS_DEFAULTS, value: undefined, revision: 0 })
     }
     for (const [ns, value] of Object.entries(pre ?? {})) {
       namespaces.set(ns, { schema: (input: unknown) => input ?? {}, value, revision: 0 })
@@ -979,7 +979,7 @@ describe('side card settings routes', () => {
 
   it('shell.get reflects the settings-page override with the quotes stripped', async () => {
     const route = mountWithSettings(createFakeSettings({
-      'dsh-apes-sidebar': {
+      [SIDEBAR_PREFS_NS]: {
         terminalShell: '"C:\\Program Files\\PowerShell\\7\\pwsh.exe"',
         terminalShellArgs: '-NoLogo',
       },
@@ -1184,7 +1184,7 @@ describe('agent terminal tool gating', () => {
     const handlerRef: { current: ((ns: string) => void) | null } = { current: null }
     const settings = {
       describe: () => [{
-        ns: 'dsh-apes-sidebar',
+        ns: SIDEBAR_PREFS_NS,
         value: { ...SIDEBAR_PREFS_DEFAULTS, agentTerminalTools: enabled },
         applies: 'live' as const,
         revision: 0,
@@ -1215,18 +1215,18 @@ describe('agent terminal tool gating', () => {
     expect(live()).toBe(0)
     // Flipping the setting on registers all eight tools.
     enabled = true
-    handlerRef.current?.('dsh-apes-sidebar')
+    handlerRef.current?.(SIDEBAR_PREFS_NS)
     expect(live()).toBe(8)
     expect(disposed).toBe(0)
     // Flipping it back off unregisters them (and releases any agent terminals).
     enabled = false
-    handlerRef.current?.('dsh-apes-sidebar')
+    handlerRef.current?.(SIDEBAR_PREFS_NS)
     expect(live()).toBe(0)
     expect(disposed).toBe(8)
     // And a redundant toggle registers them fresh (no double-registration per
     // flip: the guard only skips when the tools are already live).
     enabled = true
-    handlerRef.current?.('dsh-apes-sidebar')
+    handlerRef.current?.(SIDEBAR_PREFS_NS)
     expect(live()).toBe(8)
     expect(registered).toBe(16)
   })
@@ -1241,7 +1241,7 @@ describe('agent sidebar-open tool gating', () => {
     const handlerRef: { current: ((ns: string) => void) | null } = { current: null }
     const settings = {
       describe: () => [{
-        ns: 'dsh-apes-sidebar',
+        ns: SIDEBAR_PREFS_NS,
         value: { ...SIDEBAR_PREFS_DEFAULTS, agentOpenTools: enabled },
         applies: 'live' as const,
         revision: 0,
@@ -1272,17 +1272,17 @@ describe('agent sidebar-open tool gating', () => {
     expect(live()).toBe(0)
     // Flipping the setting on registers the single sidebar_open tool.
     enabled = true
-    handlerRef.current?.('dsh-apes-sidebar')
+    handlerRef.current?.(SIDEBAR_PREFS_NS)
     expect(live()).toBe(1)
     expect(disposed).toBe(0)
     // Flipping it back off unregisters it (and drains the undelivered queue).
     enabled = false
-    handlerRef.current?.('dsh-apes-sidebar')
+    handlerRef.current?.(SIDEBAR_PREFS_NS)
     expect(live()).toBe(0)
     expect(disposed).toBe(1)
     // And a redundant toggle registers it fresh (no double-registration).
     enabled = true
-    handlerRef.current?.('dsh-apes-sidebar')
+    handlerRef.current?.(SIDEBAR_PREFS_NS)
     expect(live()).toBe(1)
     expect(registered).toBe(2)
   })