diff --git a/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.i18n.yaml b/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.i18n.yaml
index 729001b04c..ca0d2c8d42 100644
--- a/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.i18n.yaml
+++ b/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write .agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.md
-2026-08-14-plugin-enable-disable-in-page.md: b868a8e4f84357e944c184cb80d58ea40858f7b8
-2026-08-14-plugin-enable-disable-in-page.zh.md: c53187fd067f3e208e62ecc09d361548ba61bda1
+2026-08-14-plugin-enable-disable-in-page.md: 9616cc207f8032faf61d17e5211e64ce4253dee9
+2026-08-14-plugin-enable-disable-in-page.zh.md: 1251c0aa7e57fce2364d99119c52d68540e728ae
diff --git a/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.md b/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.md
index b868a8e4f8..9616cc207f 100644
--- a/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.md
+++ b/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.md
@@ -38,13 +38,15 @@ The list is grouped: toggleable plugins carry the button in the main list, while
 the required system plugins sit in a separate collapsible "system plugins"
 section with no controls.
 
-**Guard:** every entry carries a `protected` flag. The rule is default-protect —
-disabling a plugin that another plugin injects breaks the dependent, and
-enabling one whose service is unavailable fails the boot (both surfaced as
-`dsh-tool-ralph: pending (waiting for service: workflowEngine)` after a bad
-toggle). So `setEnabled` refuses and the UI hides the toggle for every shipped
-plugin; only plugins added through an opt-in bundle (`USER_TOGGLEABLE_PLUGINS`
-in `src/required.ts`) are toggleable.
+**Guard:** every entry carries a `protected` flag. Disabling a plugin that
+another plugin injects breaks the dependent, and enabling one whose service is
+unavailable fails the boot (both surfaced as `dsh-tool-ralph: pending (waiting
+for service: workflowEngine)` after a bad toggle). So `setEnabled` refuses to
+**disable** a required plugin, and after **enabling** a plugin it verifies the
+fiber became active (reverting a dependency-missing enable). The plugin-list tab
+groups by current state: disabled plugins sit in the main list with an enable
+button, while enabled plugins sit in a collapsible system section (a user-added
+enabled plugin keeps a disable toggle, a required one shows none).
 
 ## Persistence caveat
 
diff --git a/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.zh.md b/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.zh.md
index c53187fd06..1251c0aa7e 100644
--- a/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.zh.md
+++ b/.agents/notes/implemented/feature/2026-08-14-plugin-enable-disable-in-page.zh.md
@@ -29,11 +29,12 @@ Web 插件列表 tab（`ui-settings-plugin-inventory`）在每张展开卡片的
 绑定该 Remote，切换后重新拉取列表。列表分组：可切换插件在主列表带按钮，必需的系统插件
 放在一个可折叠的"系统插件"区，无任何开关。
 
-**门卫：** 每条条目带 `protected` 标记。规则默认保护——停用一个被其他插件注入的插件会破坏
-依赖者，启用一个服务不可用的插件会导致启动失败（坏切换后都会表现为
+**门卫：** 每条条目带 `protected` 标记。停用一个被其他插件注入的插件会破坏依赖者，
+启用一个服务不可用的插件会导致启动失败（坏切换后都会表现为
 `dsh-tool-ralph: pending (waiting for service: workflowEngine)`）。所以 `setEnabled`
-拒绝、UI 隐藏所有随包插件的开关；只有通过 opt-in bundle 添加的插件
-（`src/required.ts` 的 `USER_TOGGLEABLE_PLUGINS`）可切换。
+拒绝**停用**必需插件；**启用**后校验 fiber 变为 active（依赖缺失的启用会回滚）。
+插件列表 tab 按当前状态分组：已停用插件在主列表带"启用"按钮，已启用插件放在可折叠的
+"系统插件"区（用户自加的已启用插件保留"停用"按钮，必需插件无任何开关）。
 
 ## 持久化注意
 
diff --git a/packages/client/ui-settings-plugin-inventory/src/client/PluginInventorySettingsTab.tsx b/packages/client/ui-settings-plugin-inventory/src/client/PluginInventorySettingsTab.tsx
index 9cb5ff1f16..2c0ed9fdef 100644
--- a/packages/client/ui-settings-plugin-inventory/src/client/PluginInventorySettingsTab.tsx
+++ b/packages/client/ui-settings-plugin-inventory/src/client/PluginInventorySettingsTab.tsx
@@ -98,10 +98,11 @@ export function PluginInventorySettingsTab({ list, setEnabled, t }: PluginInvent
       : [],
     [normalizedQuery, state],
   )
-  // User-added (opt-in bundle) plugins are toggleable; the rest are required
-  // system plugins shown in a separate collapsible section without toggles.
-  const userEntries = filteredEntries.filter(entry => !entry.protected)
-  const systemEntries = filteredEntries.filter(entry => entry.protected)
+  // Disabled plugins sit in the main list with an enable toggle so they can be
+  // re-enabled; enabled plugins are grouped into a collapsible system section
+  // (a user-added enabled plugin still carries a disable toggle).
+  const userEntries = filteredEntries.filter(entry => !entry.enabled)
+  const systemEntries = filteredEntries.filter(entry => entry.enabled)
 
   useEffect(() => {
     if (expanded !== null && !filteredEntries.some(entry => entry.entryId === expanded)) {
@@ -170,7 +171,17 @@ export function PluginInventorySettingsTab({ list, setEnabled, t }: PluginInvent
                 </div>
               ) : null}
             </dl>
-            {entry.protected ? (
+            {!entry.enabled ? (
+              <button
+                className={css.toggle}
+                type="button"
+                disabled={busy === entry.entryId}
+                aria-busy={busy === entry.entryId || undefined}
+                onClick={() => { toggle(entry.entryId, true) }}
+              >
+                {busy === entry.entryId ? t('toggling') : t('enable')}
+              </button>
+            ) : entry.protected ? (
               <p className={css.required}>{t('required')}</p>
             ) : (
               <button
@@ -178,9 +189,9 @@ export function PluginInventorySettingsTab({ list, setEnabled, t }: PluginInvent
                 type="button"
                 disabled={busy === entry.entryId}
                 aria-busy={busy === entry.entryId || undefined}
-                onClick={() => { toggle(entry.entryId, !entry.enabled) }}
+                onClick={() => { toggle(entry.entryId, false) }}
               >
-                {busy === entry.entryId ? t('toggling') : entry.enabled ? t('disable') : t('enable')}
+                {busy === entry.entryId ? t('toggling') : t('disable')}
               </button>
             )}
           </div>
diff --git a/packages/host/plugin-inventory/README.md b/packages/host/plugin-inventory/README.md
index d6c831f98d..1eb12840cd 100644
--- a/packages/host/plugin-inventory/README.md
+++ b/packages/host/plugin-inventory/README.md
@@ -6,7 +6,7 @@ Host projection of the current Cordis Loader tree with per-plugin enable/disable
 
 The phase is `pending`, `loading`, `active`, `failed`, or `unloading`; it is `null` when the entry has no live root Fiber. The snapshot is intentionally point-in-time: Loader remains the sole lifecycle authority, while this package owns no cache, history, provenance model, or event stream. `setEnabled` toggles one entry live through `ctx.loader.update` and persists an explicit `disabled` override into the profile's user patch layer so the choice survives a restart (a bundle-default disable needs the `disabled: false` override to stick).
 
-Every entry carries a `protected` flag. The guard is default-protect: every shipped plugin is required by the application (disabling one that another plugin injects breaks the dependent; enabling one whose service is unavailable fails the boot), so `setEnabled` refuses them and the UI hides the toggle. Only plugins a deployment adds through an opt-in bundle (`USER_TOGGLEABLE_PLUGINS` in `src/required.ts`) are toggleable. The Web plugin-list tab groups the inventory accordingly: toggleable plugins carry an enable/disable button, while the required system plugins sit in a separate collapsible "system plugins" section with no controls. Its public payload types live under `./types`, and Typert generates the Host and Client Remote artifacts exposed by `./typert` and `./remote`.
+Every entry carries a `protected` flag. The guard is default-protect: every shipped plugin is required by the application (disabling one that another plugin injects breaks the dependent; enabling one whose service is unavailable fails the boot), so `setEnabled` refuses them and the UI hides the toggle. Only plugins a deployment adds through an opt-in bundle (`USER_TOGGLEABLE_PLUGINS` in `src/required.ts`) are toggleable. The Web plugin-list tab groups the inventory by current state: disabled plugins sit in the main list with an enable button (so they can be re-enabled), while enabled plugins sit in a collapsible "system plugins" section — a user-added enabled plugin keeps a disable toggle, a required one shows none. Its public payload types live under `./types`, and Typert generates the Host and Client Remote artifacts exposed by `./typert` and `./remote`.
 
 The service is Remote-only and deliberately declares no same-process Cordis `Context` merge. Client packages consume it through the explicit [`api-remotes`](../../api/remotes/README.md) assembly rather than importing the Host implementation.
 
diff --git a/packages/host/plugin-inventory/README.zh.md b/packages/host/plugin-inventory/README.zh.md
index f39dc22b02..c52f066d49 100644
--- a/packages/host/plugin-inventory/README.zh.md
+++ b/packages/host/plugin-inventory/README.zh.md
@@ -6,7 +6,7 @@
 
 阶段为 `pending`、`loading`、`active`、`failed` 或 `unloading`；条目没有存活的根 Fiber 时则为 `null`。该快照刻意只表示调用当下：Loader 仍是唯一的生命周期权威，本包不拥有缓存、历史、来源模型或事件流。`setEnabled` 通过 `ctx.loader.update` 实时切换单条条目，并把显式 `disabled` 覆盖写进 profile 的用户补丁层，使选择在重启后保留（bundle 默认禁用的行需要 `disabled: false` 覆盖才能保持启用）。
 
-每条条目带 `protected` 标记。守卫默认保护：所有随包插件都是应用必需（停用一个被其他插件注入的插件会破坏依赖者；启用一个服务不可用的插件会导致启动失败），所以 `setEnabled` 拒绝它们、UI 隐藏开关。只有部署通过 opt-in bundle 添加的插件（`src/required.ts` 的 `USER_TOGGLEABLE_PLUGINS`）可切换。Web 插件列表 tab 据此分组：可切换插件带启用/停用按钮，必需的系统插件放在一个可折叠的"系统插件"区，无任何开关。公开 payload 类型位于 `./types`，Typert 生成由 `./typert` 与 `./remote` 导出的 Host 和 Client Remote 产物。
+每条条目带 `protected` 标记。守卫默认保护：所有随包插件都是应用必需（停用一个被其他插件注入的插件会破坏依赖者；启用一个服务不可用的插件会导致启动失败），所以 `setEnabled` 拒绝它们、UI 隐藏开关。只有部署通过 opt-in bundle 添加的插件（`src/required.ts` 的 `USER_TOGGLEABLE_PLUGINS`）可切换。Web 插件列表 tab 按当前状态分组：已停用插件在主列表带"启用"按钮（可重新启用），已启用插件放在可折叠的"系统插件"区——用户自加的已启用插件仍保留"停用"按钮，必需插件则无任何开关。公开 payload 类型位于 `./types`，Typert 生成由 `./typert` 与 `./remote` 导出的 Host 和 Client Remote 产物。
 
 该服务仅供 Remote 使用，刻意不声明同进程 Cordis `Context` merge。Client 包通过显式的 [`api-remotes`](../../api/remotes/README.md) 组合消费它，而不导入 Host 实现。
 
diff --git a/packages/host/plugin-inventory/src/index.ts b/packages/host/plugin-inventory/src/index.ts
index f89f087843..3addeb9e90 100644
--- a/packages/host/plugin-inventory/src/index.ts
+++ b/packages/host/plugin-inventory/src/index.ts
@@ -89,11 +89,19 @@ export class PluginInventoryGateway extends TypertRemoteService {
     if (entry === undefined) {
       throw new Error(`plugin entry ${String(entryId)} not found`)
     }
-    if (isRequiredPlugin(entry.options.name)) {
-      throw new Error(`plugin ${String(entryId)} is required by the application and cannot be toggled`)
+    // Disabling a required system plugin tears the process down; refuse it.
+    // Re-enabling a disabled plugin is what this surface is for.
+    if (!enabled && isRequiredPlugin(entry.options.name)) {
+      throw new Error(`plugin ${String(entryId)} is required by the application and cannot be disabled`)
     }
     const rowId = entry.options.id
     await this.ctx.loader.update(entryId, { disabled: !enabled })
+    // An enable whose injected services are unavailable would fail the next
+    // boot (the dependent never becomes active). Revert and refuse loudly.
+    if (enabled && entry.fiber !== undefined && entry.fiber.state !== FIBER_STATE.ACTIVE) {
+      await this.ctx.loader.update(entryId, { disabled: true })
+      throw new Error(`plugin ${String(entryId)} could not start; its dependencies are unavailable`)
+    }
     if (this.ctx.baseUrl !== undefined) {
       persistPluginDisabled(fileURLToPath(this.ctx.baseUrl), rowId, !enabled)
     }