diff --git a/AGENTS.md b/AGENTS.md
index f2442a1..dcac287 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -38,6 +38,7 @@
 7. **`@deepseek-ai/dsh-client-runtime` 包已消亡**（继任 seed 是裸名 `dsh-client-store`，无 `/client` 子路径）：peerDependencies、devDependencies、`dsh.client.inject`、chunk externals 白名单（`src/client/chunk-loader.ts` / `tsdown.config.ts` / `tests/chunk-loader.spec.ts` / `tests/manifest-consistency.spec.ts` 四处同步）均已无该条目。
 8. **e2e scratch profile 的 `minimumReleaseAgeExclude` 含 `'@deepseek-ai/*'`**（`scripts/e2e-mount.sh` / `e2e-aggregate-mount.sh`，与仓库根 `pnpm-workspace.yaml` 同策）：alpha 版本常在发布后 24h 内跑 lane，pnpm 11 的 `minimumReleaseAge` 默认会拒装新鲜包。
 9. **插件开发树的 dsh-* 传递 peer 需提升为 devDependencies**（alpha.3 首见）：`dsh-subagent` 等 npm 包把 `dsh-attachment` 等 dsh-* 姊妹包全部声明为 peerDependencies（由宿主 bundle 树统一提供，宿主侧无此问题），插件仓库若只直接依赖其中一部分，其余 peer 在 pnpm 下会解析到树上残留的旧版——如 `dsh-attachment@0.1.1-rc.1` 缺 `admitPromptContent` 导出、`dsh-subagent` 产物 import 它时测试加载即崩。因此 devDependencies 需涵盖 dev 树实际触达的全部 peer（attachment / code-runtime / scope / session-projection / system-prompt / user-approval / util-time 七个即为此提升，与直接依赖同款精确钉版）；`@deepseek-ai/cordis` peer 自 alpha.3 起要求 `^4.0.2`（上游全线 peer 已升）。适配新 alpha 版本时先跑 `pnpm peers check`，把新失配的传递 peer 一并提升进 devDependencies。例外：**`dsh-client-locale` 的 peer/devDep 允许落后于基线**（alpha.5 时上游停在 0.1.2-alpha.3 未发新版）——peer 下限 `^0.1.2-alpha.3` 天然容纳同 tuple 的 alpha.5 运行时，此时保持旧钉版并在 `pnpm-workspace.yaml` 注明，待上游发版再追平。
+10. **聊天文件打开漏斗是 `remote.session.openWorkspacePath`**（`ctx.workspaces.openPath` 已随 alpha 删除，`IWorkspaces` 无此方法）：「聊天区文件在侧边栏打开」拦截在 `ctx.inject(['remote.session'], …)` 内以 **defineProperty 数据属性遮蔽**该命名空间方法（gateway client 的方法是 accessor 属性、异步挂载、contribution 重挂载时服务重建——inject 回调重跑即自愈）；实现见 `src/client/openpath-intercept.ts`，设计见 [docs/plans/2026-08-31-openpath-intercept-alpha-design.md](docs/plans/2026-08-31-openpath-intercept-alpha-design.md)。
 
 ---
 
diff --git a/docs/external-plugin-guide.md b/docs/external-plugin-guide.md
index bf6f3ae..d9070d4 100644
--- a/docs/external-plugin-guide.md
+++ b/docs/external-plugin-guide.md
@@ -727,6 +727,7 @@ ctx.effect(() =>
 | **i18n 跟随** | 文案跟随 DSH `ctx.locale`（词典在 `betterSidebar` 命名空间；Host-backed `locale.preference` 优先于浏览器语言并实时切换；缺失回退浏览器）。消费插件**不要**依赖内部 `t()`——标题传字符串或 `() => string` |
 | **第三语言覆盖（ja 等）** | 可选 peer `@huanlin/dsh-plugin-better-locale`（optional）提供 ja/ko 覆盖，**借用 DSH 英文槽位**（仅 DSH=en 时生效，zh 下惰性）。经 `ctx.get('betterLocale')` 注入 `t()`；未安装整段 no-op |
 | **懒加载 chunk** | 重依赖（xterm/CodeMirror）在独立 bundle（`lib/client-<name>.js`），经 `/sidebar/bundle` 按需下发；factory 赋到 `globalThis.__dshChunks__[<name>]`，由 `src/client/chunk-loader.ts` 物化，**不经** `__ModuleLoader__`。对消费插件透明 |
+| **聊天文件打开漏斗（alpha 宿主）** | 聊天里一切文件打开（工具行 / 产物行 / 正文提及 / 行内代码路径）汇入 `ctx.remote.session.openWorkspacePath`（Typert remote 命名空间，cordis 服务 key `remote.session`，方法为 **accessor 属性**、异步挂载）。better-sidebar 的「聊天区文件在侧边栏打开」即在 `ctx.inject(['remote.session'], …)` 内以 defineProperty 遮蔽该方法（`src/client/openpath-intercept.ts`）。你的插件若要观测/旁路聊天文件打开，走同一服务；不要假设 pre-alpha 的 `ctx.workspaces.openPath` 存在（alpha 的 `IWorkspaces` 已无此方法） |
 
 ---
 
diff --git a/docs/plans/2026-08-31-openpath-intercept-alpha-design.md b/docs/plans/2026-08-31-openpath-intercept-alpha-design.md
new file mode 100644
index 0000000..575f4ee
--- /dev/null
+++ b/docs/plans/2026-08-31-openpath-intercept-alpha-design.md
@@ -0,0 +1,72 @@
+# 聊天文件打开拦截的 0.1.2-alpha 适配（openPath 漏斗迁移）
+
+日期：2026-08-31　分支：`fix/openpath-intercept-alpha`
+
+## 问题
+
+0.1.2-alpha.x 宿主上，聊天里点击文件链接（工具行、产物行、正文行内代码路径）直接落到系统默认应用（Linux 即 `xdg-open`），「聊天区文件在侧边栏打开」（`interceptOpenPath`，默认开）形同虚设。
+
+**根因**：alpha 架构把聊天打开文件的漏斗从客户端服务换成了远程调用——`ui-chat/src/client/apply.ts` 注入 ChatView 的 `openFile` 直连 `ctx.remote.session.openWorkspacePath({ path })` → 宿主 `session-controller` → `openNativePath`。插件的 `wrapOpenPath` 包的是旧漏斗 `ctx.workspaces.openPath`，而 alpha 的 `IWorkspaces`（`api/workspace-controller/src/client/service.ts`）**已删除 `openPath` 方法**——wrap 只是给 service 实例挂了个永无调用方的新属性，死代码。这是 #435/#472 适配的漏网项（挂载冒烟不点聊天文件链接，抓不到）。
+
+**连带影响**：#158 的聊天路径/行号超链接（`owner.openFile` → openPath 假设）同样失效。（#171 的「以默认应用打开」旁路 `openPathWithSystem` 已随重构消失，现行走插件自有 `open.external` 路由，不受影响。）
+
+**版本前提**：插件已进 alpha 通道（#472，peer `^0.1.2-alpha.2`，pre-alpha 兼容层已删）——本修复只面向 alpha 宿主，**整体替换**旧漏斗，不做双版本兼容。
+
+## 新漏斗的事实（宿主源码核实）
+
+1. **唯一生产调用方**：`ui-chat` apply 的 `openFile` 注入（工具行 / 产物行 / 正文提及 / 行内代码路径全部经 ChatView 的 `requestOpenFile` 汇入）。调用前路径已被 `resolveWorkspacePath(cwd, path)` 解析成绝对路径——与旧漏斗收到的形态一致。`canOpenWorkspacePath` 仅被 ui-deliverables 用于按钮可见性，无打开语义，不拦。
+2. **`remote.session` 是 cordis 服务**（gateway client 的 `RemoteNamespaceService`，service key `remote.session`，经 `ctx.plugin` 注册）：
+   - 方法以 `Object.defineProperty(service, method, { configurable: true, enumerable: true, get })` 安装，getter 在**访问时**读 `methods` 表返回调用闭包（因此直接赋值包装无效——无 setter）；
+   - 命名空间整组方法与 service 构造在**同一同步窗口**安装——`ctx.inject(['remote.session'], cb)` 回调触发时方法必已就位；
+   - contribution 卸载/重挂载时服务 dispose/重建，inject 回调随之重跑——包装天然自愈。
+3. 宿主端成功返回 `{ opened: true }`；失败抛 TypertRemoteFailure（ChatView 弹错误框）。接管方必须返回同形成功值。
+
+## 方案：`wrapOpenWorkspacePath`（沿用「包单漏斗」模式，defineProperty 版）
+
+改写 `src/client/openpath-intercept.ts`：
+
+```ts
+// 伪代码
+const descriptor = Object.getOwnPropertyDescriptor(service, 'openWorkspacePath')
+const original = service.openWorkspacePath            // 访问 getter，捕获当前调用闭包
+Object.defineProperty(service, 'openWorkspacePath', {
+  configurable: true, enumerable: true, writable: true,
+  value: (request: { path: string }, signal?: AbortSignal) => {
+    if (takeover()) { /* 接管 */ return Promise.resolve({ opened: true }) }
+    return original.call(service, request, signal)    // 放行 = 宿主 native open
+  },
+})
+// dispose：descriptor 存在则原样 defineProperty 恢复，否则 delete —— HMR 安全
+```
+
+- **接管语义不变**（复用现有 deps）：`!suspended && interceptOpenPath !== false && tabsEnabled.editor !== false && 有 current session`；`isFolderRevealPath` → `revealInExplorer`；其余 → `openInSidebar`（`:line` 拆分在既有链路内，#158 功能随之恢复）。
+- **进入时机**：`registerOpenPathInterception` 改为 `ctx.inject(['remote.session'], ...)` 内包装；宿主裁掉该服务时回调永不触发 = 不拦截不报错。
+- **已知取舍**：包装期间若 contribution 重挂方法记录，捕获的 `original` 闭包指向旧记录（getter 访问期绑定语义决定）；session 命名空间实际常驻，可接受，代码注释记录。
+
+## 改动清单
+
+| 文件 | 变更 |
+|------|------|
+| `src/client/openpath-intercept.ts` | 重写为 `wrapOpenWorkspacePath`（defineProperty 包装/恢复）；`isFolderRevealPath` 保留 |
+| `src/client/intercept.tsx` | `registerOpenPathInterception` 改走 `ctx.inject(['remote.session'], …)`；deps 不变 |
+| `src/context-types.ts` | `SidebarWorkspacesService{openPath}` 替换为 `SidebarRemoteSessionService{openWorkspacePath(request): Promise<{opened: boolean}>}` |
+| `src/client/index.tsx` | inject 数组移除 `'workspaces'`（全仓唯一消费者是旧拦截，typecheck 验证后删） |
+| `tests/openpath-intercept.spec.ts` | 重写：getter 形态假服务、接管/放行/恢复、inject 晚到场景 |
+| `docs/external-plugin-guide.md` | §10 平台陷阱补「聊天文件打开拦截走 remote.session.openWorkspacePath」一条 |
+| AGENTS.md §3 | 新增一条 alpha 宿主契约记录（对齐 #463 的做法） |
+
+## 验证
+
+- 单测：接管 / 放行 / 文件夹揭示手势三态；dispose 恢复原 descriptor；inject 延迟出现。
+- 门禁：`pnpm typecheck` → `pnpm test` → `pnpm build` → `pnpm test:mount`（alpha.2 真机 14/14 不回归；mount lane 不驱动聊天点击，拦截正确性靠单测 + 手测）。
+- 真机手测：让模型在回复里输出一个工作区文件路径（行内代码）→ 点击落侧边栏编辑器；关闭「聊天区文件在侧边栏打开」后点击 → 系统默认应用；`path:line` 链接 → 侧边栏跳行（#158 回归）。
+
+## 实施偏差记录
+
+- **接管返回值必须是 typert `RemoteResult` 包络**（初版实现踩坑修正）：plan 中「接管返回 `{ opened: true }`」有误——gateway client 的每个 remote 方法都把业务值折叠成 `{ ok: true, value }` / `{ ok: false, error }`，ChatView 的 `openFile` 按 `result.ok` 分支、falsy 时读 `result.error.message`。初版返回裸业务值导致「文件已在侧边栏打开，但仍弹『无法打开文件: Cannot read properties of undefined (reading 'message')』」。修正为接管时返回 `{ ok: true, value: { opened: true } }`（`OpenWorkspacePathResult` 类型钉住，单测断言包络形状）。
+
+## 不做
+
+- pre-alpha 双版本兼容（alpha-only 通道，#472 已删兼容层）。
+- `canOpenWorkspacePath` 包装（仅按钮可见性）。
+- DSH 侧任何改动（仓库硬约束 §1）。
diff --git a/src/client/index.tsx b/src/client/index.tsx
index ff25c8a..2915d42 100644
--- a/src/client/index.tsx
+++ b/src/client/index.tsx
@@ -34,8 +34,10 @@ import './layout.css'
  *  (rc.8+) is the client module system the chunk loader resolves its
  *  externals through; `connection` (0.1.2-alpha.2+) is the Remote transport's
  *  recovery lifecycle the side chat's disconnect banner reads — Cordis guards
- *  service access without inject. */
-export const inject = ['slots', 'sessions', 'workspaces', 'locale', 'modules', 'connection']
+ *  service access without inject. The `remote.session` namespace is NOT here:
+ *  it mounts asynchronously, so the open-path interception reaches it through
+ *  `ctx.inject` (see intercept.tsx). */
+export const inject = ['slots', 'sessions', 'locale', 'modules', 'connection']
 
 /**
  * Error boundary over the sidebar tree (root scope): a render error in the
diff --git a/src/client/intercept.tsx b/src/client/intercept.tsx
index f55de6c..8630a8b 100644
--- a/src/client/intercept.tsx
+++ b/src/client/intercept.tsx
@@ -11,7 +11,7 @@ import type { Context } from '../context-types.ts'
 import { firstLeaf, revealPaths, togglePanel, type SidebarStore } from './state.ts'
 import { t } from './locales.ts'
 import { resolveSidebarPath, selectProducedFiles } from './produced-files.ts'
-import { wrapOpenPath } from './openpath-intercept.ts'
+import { wrapOpenWorkspacePath, type OpenWorkspacePathService } from './openpath-intercept.ts'
 import css from './sidebar.module.css'
 
 /** Open a file in the sidebar's editor (used by the intercepted row and the explorer). */
@@ -151,22 +151,36 @@ export function registerTurnTailInterception(ctx: Context, store: SidebarStore):
 }
 
 /**
- * Register the chat file-open interception: wraps `ctx.workspaces.openPath`
- * — the single funnel every chat-side file open goes through (tool-row path
- * links, the produced-files row, prose mentions) — so opens land in the
- * sidebar editor instead of the Host OS. The folder-reveal gesture ("Show in
- * folder" passes `'.'`) is the one exception: it is routed to the explorer.
- * Gated by BOTH the `interceptOpenPath` pref and the editor tab's enable
- * switch; declined opens fall through to the original method. Returns the
- * disposer restoring the original (HMR-safe).
+ * Register the chat file-open interception: shadows
+ * `remote.session.openWorkspacePath` — the single funnel every chat-side
+ * file open goes through on alpha hosts (tool-row path links, the
+ * produced-files row, prose mentions, inline-code paths) — so opens land in
+ * the sidebar editor instead of the Host OS. The folder-reveal gesture
+ * ("Show in folder" passes `'.'`) is the one exception: it is routed to the
+ * explorer. Gated by BOTH the `interceptOpenPath` pref and the editor tab's
+ * enable switch; declined opens fall through to the original remote call.
+ *
+ * The `remote.session` namespace service mounts asynchronously (the gateway
+ * client creates it when the session-controller contribution arrives) and
+ * is recreated on contribution remounts, so the wrapper installs through
+ * `ctx.inject`: the callback runs once the service exists and re-runs after
+ * every remount, re-applying the shadow on the fresh instance. Returns the
+ * disposer (disposes the inject fiber, which restores the original method
+ * descriptor — HMR-safe).
  */
 export function registerOpenPathInterception(ctx: Context, store: SidebarStore): () => void {
-  return wrapOpenPath(ctx.workspaces, {
-    takeoverEnabled: () => !store.getSuspended()
-      && store.getPrefs().interceptOpenPath !== false
-      && store.getPrefs().tabsEnabled['editor'] !== false,
-    currentSessionId: () => ctx.sessions.list.getSnapshot().current,
-    openInSidebar: (path, sessionId) => { openSidebarFile(ctx, store, sessionId, path) },
-    revealInExplorer: (_path, sessionId) => { revealInExplorer(ctx, store, sessionId, lastProduced) },
+  const fiber = ctx.inject(['remote.session'], (fctx) => {
+    fctx.effect(() => {
+      const service = fctx.get('remote.session') as OpenWorkspacePathService
+      return wrapOpenWorkspacePath(service, {
+        takeoverEnabled: () => !store.getSuspended()
+          && store.getPrefs().interceptOpenPath !== false
+          && store.getPrefs().tabsEnabled['editor'] !== false,
+        currentSessionId: () => ctx.sessions.list.getSnapshot().current,
+        openInSidebar: (path, sessionId) => { openSidebarFile(ctx, store, sessionId, path) },
+        revealInExplorer: (_path, sessionId) => { revealInExplorer(ctx, store, sessionId, lastProduced) },
+      })
+    }, 'dsh-better-sidebar: open-path interception wrap')
   })
+  return () => { void fiber.dispose() }
 }
diff --git a/src/client/openpath-intercept.ts b/src/client/openpath-intercept.ts
index 4bac265..f87e05d 100644
--- a/src/client/openpath-intercept.ts
+++ b/src/client/openpath-intercept.ts
@@ -1,21 +1,57 @@
 /**
- * Interception of the chat's file-open funnel. The client runtime's
- * `ctx.workspaces.openPath` is the SINGLE door every chat-side file open goes
- * through — ui-conversation's apply.ts resolves the path against the session
- * cwd and calls it for tool-row path links, the produced-files row, and
- * prose file mentions alike (verified against the DSH source:
- * `packages/client/ui-conversation/src/client/apply.ts` is the only
- * production caller). Wrapping that one method reroutes those opens into the
- * sidebar editor instead of the Host OS — no DSH modification needed.
+ * Interception of the chat's file-open funnel (DSH 0.1.2-alpha hosts).
+ *
+ * The alpha funnel is the Typert remote namespace `remote.session`: every
+ * chat-side file open (tool-row path links, the produced-files row, prose
+ * file mentions, inline-code paths) funnels through ChatView's injected
+ * `openFile`, which calls `ctx.remote.session.openWorkspacePath({ path })`
+ * with the path ALREADY resolved against the session cwd (verified against
+ * the DSH source: `packages/client/ui-chat/src/client/apply.ts` is the only
+ * production caller). The host side (`api/session-controller`) hands the
+ * path to the OS's default application (`openNativePath` → xdg-open on
+ * Linux). The pre-alpha funnel `ctx.workspaces.openPath` is gone — the
+ * alpha `IWorkspaces` has no openPath at all.
+ *
+ * `remote.session` is a cordis service (the gateway client's
+ * RemoteNamespaceService, key `remote.session`) whose methods are installed
+ * as ACCESSOR properties (`Object.defineProperty(service, method, {
+ * configurable: true, get })`) — the getter reads the method table at
+ * ACCESS time and returns the invocation closure. A plain assignment would
+ * not stick (no setter), so the wrapper shadows the method with a data
+ * property and restores the captured accessor descriptor on dispose.
+ *
+ * The namespace service appears asynchronously (the session-controller
+ * contribution mounts after the connection is up) and is disposed/recreated
+ * on contribution remounts; the caller therefore enters through
+ * `ctx.inject(['remote.session'], …)`, which re-fires on every remount.
  *
  * The wrapper is dependency-free by design (no React / ui-primitives), so
- * the takeover logic is unit-testable and the file stays importable from the
- * test runtime.
+ * the takeover logic is unit-testable and the file stays importable from
+ * the test runtime.
  */
 
-/** The one service method the wrapper replaces (mirror of the runtime IWorkspaces). */
-export interface OpenPathService {
-  openPath(path: string): Promise<void>
+/** The one request shape the funnel method takes (mirror of the host's
+ *  SessionOpenWorkspacePathRequest). */
+export interface OpenWorkspacePathRequest {
+  /** Absolute path (the chat caller already resolved it against the cwd). */
+  path: string
+}
+
+/**
+ * What the funnel method resolves to (mirror of the typert `RemoteResult`
+ * envelope): EVERY remote method folds its business value into
+ * `{ ok: true, value }` / `{ ok: false, error }` — the chat caller branches
+ * on `result.ok`, so a bare business value would be misread as a failure
+ * (`result.error.message` reads `message` off undefined).
+ */
+export type OpenWorkspacePathResult =
+  | { readonly ok: true; readonly value: { opened: boolean } }
+  | { readonly ok: false; readonly error: { readonly code: string; readonly message: string; readonly details: object } }
+
+/** The namespace slice the wrapper shadows (mirror of the gateway client's
+ *  RemoteNamespaceService for the `session` namespace). */
+export interface OpenWorkspacePathService {
+  openWorkspacePath(request: OpenWorkspacePathRequest, signal?: AbortSignal): Promise<OpenWorkspacePathResult>
 }
 
 /** Per-call decisions the wrapper needs (wired to the store + ctx in the client half). */
@@ -48,32 +84,61 @@ export function isFolderRevealPath(path: string): boolean {
 }
 
 /**
- * Wrap `workspaces.openPath`: intercepted calls open the file in the sidebar
- * editor instead of the Host OS and resolve as success (the original's
- * callers ignore the result); anything that declines falls through to the
- * original method untouched. The one exception is the folder-reveal gesture,
- * which is routed to {@link OpenPathInterceptDeps.revealInExplorer} instead.
- * @param workspaces - the client workspaces service to wrap.
+ * Shadow `remote.session.openWorkspacePath`: intercepted calls open the file
+ * in the sidebar editor and resolve with the remote SUCCESS ENVELOPE
+ * (`{ ok: true, value: { opened: true } }`, so ChatView shows no error
+ * dialog); anything that declines falls through to the captured original
+ * closure (the host OS's default application) untouched.
+ * The one exception is the folder-reveal gesture, which is routed to
+ * {@link OpenPathInterceptDeps.revealInExplorer} instead.
+ *
+ * The original closure is captured by ACCESSING the accessor once at wrap
+ * time — it invokes whatever method records are mounted at that moment. If
+ * the contribution remounts its methods while the shadow is installed, the
+ * captured closure points at the old records; the session namespace is
+ * effectively permanent in practice, so this is accepted and the shadow is
+ * re-applied anyway when the remount recreates the service (the caller's
+ * `ctx.inject` re-fires).
+ *
+ * @param service - the `remote.session` namespace service.
  * @param deps - per-call takeover decisions.
- * @returns the disposer restoring the original method (HMR-safe).
+ * @returns the disposer restoring the original accessor descriptor (HMR-safe).
  */
-export function wrapOpenPath(workspaces: OpenPathService, deps: OpenPathInterceptDeps): () => void {
-  // The RAW method reference (never a bound copy): restore must put back the
-  // exact original so a chain of wrappers (other plugins wrapping the same
-  // method) keeps working across disposals in any order.
-  const original = workspaces.openPath
-  workspaces.openPath = (path: string): Promise<void> => {
+export function wrapOpenWorkspacePath(
+  service: OpenWorkspacePathService,
+  deps: OpenPathInterceptDeps,
+): () => void {
+  const KEY = 'openWorkspacePath'
+  const target = service as object
+  const descriptor = Object.getOwnPropertyDescriptor(target, KEY)
+  // Invoke the accessor once to capture the CURRENT invocation closure.
+  const original = service.openWorkspacePath
+  // The gateway installs the namespace's whole method group in the same
+  // synchronous window as the service registration, so an inject-observed
+  // service always has the method — but a hand-rolled composition might not;
+  // wrapping nothing would turn fall-throughs into crashes, so decline.
+  if (typeof original !== 'function') return () => {}
+  const wrapped = (request: OpenWorkspacePathRequest, signal?: AbortSignal): Promise<OpenWorkspacePathResult> => {
     if (deps.takeoverEnabled()) {
       const sessionId = deps.currentSessionId()
       if (sessionId !== undefined) {
-        if (isFolderRevealPath(path)) deps.revealInExplorer(path, sessionId)
-        else deps.openInSidebar(path, sessionId)
-        return Promise.resolve()
+        if (isFolderRevealPath(request.path)) deps.revealInExplorer(request.path, sessionId)
+        else deps.openInSidebar(request.path, sessionId)
+        return Promise.resolve({ ok: true, value: { opened: true } })
       }
     }
-    return original.call(workspaces, path)
+    return original.call(service, request, signal)
   }
+  Object.defineProperty(target, KEY, {
+    configurable: true,
+    enumerable: true,
+    writable: true,
+    value: wrapped,
+  })
   return () => {
-    workspaces.openPath = original
+    // Restore the exact original property (the gateway's accessor) so a
+    // chain of wrappers keeps working across disposals in any order.
+    if (descriptor !== undefined) Object.defineProperty(target, KEY, descriptor)
+    else Reflect.deleteProperty(target, KEY)
   }
 }
diff --git a/src/context-types.ts b/src/context-types.ts
index d52f385..55e3076 100644
--- a/src/context-types.ts
+++ b/src/context-types.ts
@@ -407,14 +407,27 @@ export interface SidebarConversation {
 }
 
 /**
- * The client workspaces service face (mirror of the runtime IWorkspaces). Only
- * the chat's file-open funnel is touched: `openPath` hands an absolute path
- * to the Host OS's default application, and every chat-side file open
- * (tool rows, produced-files, prose mentions) funnels through it.
+ * The client `remote.session` namespace face (mirror of the gateway client's
+ * RemoteNamespaceService for the session-controller contribution on alpha
+ * hosts). The chat's file-open funnel is `openWorkspacePath`: the caller
+ * resolves the path against the session cwd, and the host hands it to the
+ * OS's default application. Namespace methods are accessor properties (see
+ * `client/openpath-intercept.ts` for how the interception shadows them).
  */
-export interface SidebarWorkspacesService {
-  /** Open a filesystem path with the Host operating system's default application. */
-  openPath(path: string): Promise<void>
+export interface SidebarRemoteSessionService {
+  /**
+   * Open an absolute path with the Host operating system's default
+   * application. Resolves with the typert `RemoteResult` envelope
+   * (`{ ok: true, value: { opened } }` / `{ ok: false, error }`), like every
+   * remote method — callers branch on `result.ok`.
+   */
+  openWorkspacePath(
+    request: { path: string },
+    signal?: AbortSignal,
+  ): Promise<
+    | { readonly ok: true; readonly value: { opened: boolean } }
+    | { readonly ok: false; readonly error: { readonly code: string; readonly message: string; readonly details: object } }
+  >
 }
 
 /**
@@ -499,8 +512,6 @@ export interface SidebarContextShape {
   webRuntime: SidebarWebRuntime
   /** The client slot registry (register/inject). */
   slots: SidebarSlotsService
-  /** The client workspaces service face (file-open funnel). */
-  workspaces: SidebarWorkspacesService
   /** The settings service face (prefs persistence + namespace reads). */
   settings: SidebarSettingsService
   /** The invariant registry face. */
diff --git a/src/prefs-shared.ts b/src/prefs-shared.ts
index a40a212..3e1ac12 100644
--- a/src/prefs-shared.ts
+++ b/src/prefs-shared.ts
@@ -63,9 +63,9 @@ export interface SidebarPrefs {
   /**
    * Whether chat-side file opens (tool-row path links, the produced-files
    * row, prose file mentions — every path that funnels through the client
-   * runtime's `ctx.workspaces.openPath`) open in the sidebar editor instead
-   * of the Host OS's default application. On by default; the editor tab's
-   * own enable switch gates it too (both must be on for the takeover).
+   * runtime's `remote.session.openWorkspacePath`) open in the sidebar editor
+   * instead of the Host OS's default application. On by default; the editor
+   * tab's own enable switch gates it too (both must be on for the takeover).
    */
   interceptOpenPath: boolean
   /**
diff --git a/tests/openpath-intercept.spec.ts b/tests/openpath-intercept.spec.ts
index 619928b..76f8697 100644
--- a/tests/openpath-intercept.spec.ts
+++ b/tests/openpath-intercept.spec.ts
@@ -1,148 +1,281 @@
 import { describe, expect, it } from 'vitest'
 import { registerOpenPathInterception } from '../src/client/intercept.tsx'
-import { wrapOpenPath, type OpenPathInterceptDeps, type OpenPathService } from '../src/client/openpath-intercept.ts'
+import {
+  isFolderRevealPath,
+  wrapOpenWorkspacePath,
+  type OpenPathInterceptDeps,
+  type OpenWorkspacePathService,
+} from '../src/client/openpath-intercept.ts'
 import { createSidebarStore } from '../src/client/state.ts'
 import type { Context } from '../src/context-types.ts'
 
-describe('open-path interception', () => {
-  /** A minimal fake of the workspaces.openPath service method. */
-  const service = (): OpenPathService & { calls: string[]; opened: string[] } => {
-    const fake = {
-      calls: [] as string[],
-      opened: [] as string[],
-      async openPath(path: string): Promise<void> {
-        this.calls.push(path)
-        this.opened.push(path)
-      },
-    }
-    return fake
-  }
+/**
+ * A fake of the gateway client's RemoteNamespaceService: the method is an
+ * ACCESSOR property (getter returning the invocation closure), exactly like
+ * `Object.defineProperty(service, method, { configurable: true, get })` in
+ * the real implementation — the wrapper must shadow it with a data property
+ * and restore the accessor on dispose.
+ */
+function fakeNamespaceService(opened: string[]): OpenWorkspacePathService {
+  const target = {} as Record<string, unknown>
+  Object.defineProperty(target, 'openWorkspacePath', {
+    configurable: true,
+    enumerable: true,
+    get() {
+      return async (request: { path: string }) => {
+        opened.push(request.path)
+        return { ok: true, value: { opened: true } } as const
+      }
+    },
+  })
+  return target as unknown as OpenWorkspacePathService
+}
 
+describe('open-path interception (wrapOpenWorkspacePath)', () => {
   const deps = (overrides: Partial<OpenPathInterceptDeps> = {}): OpenPathInterceptDeps & {
     sidebar: string[]
+    revealed: string[]
   } => {
     const sidebar: string[] = []
+    const revealed: string[] = []
     return {
       sidebar,
+      revealed,
       takeoverEnabled: () => true,
       currentSessionId: () => 's1',
       openInSidebar: (path, sessionId) => { sidebar.push(`${sessionId}:${path}`) },
-      revealInExplorer: () => {},
+      revealInExplorer: (path, sessionId) => { revealed.push(`${sessionId}:${path}`) },
       ...overrides,
     }
   }
 
-  it('routes an intercepted open into the sidebar and resolves without the original call', async () => {
-    const ws = service()
+  it('routes an intercepted open into the sidebar and resolves with the remote success envelope', async () => {
+    const opened: string[] = []
+    const service = fakeNamespaceService(opened)
     const d = deps()
-    const restore = wrapOpenPath(ws, d)
-    await expect(ws.openPath('/abs/a.ts')).resolves.toBeUndefined()
-    expect(ws.calls).toEqual([])
+    const restore = wrapOpenWorkspacePath(service, d)
+    // The caller (ChatView's openFile) branches on `result.ok` and reads
+    // `result.error.message` on falsy — a bare business value would surface
+    // as a bogus "cannot open" dialog.
+    await expect(service.openWorkspacePath({ path: '/abs/a.ts' }))
+      .resolves.toEqual({ ok: true, value: { opened: true } })
+    expect(opened).toEqual([])
     expect(d.sidebar).toEqual(['s1:/abs/a.ts'])
     restore()
   })
 
   it('falls through to the original when the takeover is disabled', async () => {
-    const ws = service()
+    const opened: string[] = []
+    const service = fakeNamespaceService(opened)
     const d = deps({ takeoverEnabled: () => false })
-    const restore = wrapOpenPath(ws, d)
-    await ws.openPath('/abs/a.ts')
-    expect(ws.opened).toEqual(['/abs/a.ts'])
+    const restore = wrapOpenWorkspacePath(service, d)
+    await service.openWorkspacePath({ path: '/abs/a.ts' })
+    expect(opened).toEqual(['/abs/a.ts'])
     expect(d.sidebar).toEqual([])
     restore()
   })
 
   it('falls through when no session is current (nothing to scope the editor load to)', async () => {
-    const ws = service()
+    const opened: string[] = []
+    const service = fakeNamespaceService(opened)
     const d = deps({ currentSessionId: () => undefined })
-    const restore = wrapOpenPath(ws, d)
-    await ws.openPath('/abs/a.ts')
-    expect(ws.opened).toEqual(['/abs/a.ts'])
+    const restore = wrapOpenWorkspacePath(service, d)
+    await service.openWorkspacePath({ path: '/abs/a.ts' })
+    expect(opened).toEqual(['/abs/a.ts'])
     expect(d.sidebar).toEqual([])
     restore()
   })
 
   it('passes the current session into the sidebar opener', async () => {
-    const ws = service()
+    const opened: string[] = []
+    const service = fakeNamespaceService(opened)
     let current = 's1'
     const d = deps({ currentSessionId: () => current })
-    const restore = wrapOpenPath(ws, d)
-    await ws.openPath('/abs/a.ts')
+    const restore = wrapOpenWorkspacePath(service, d)
+    await service.openWorkspacePath({ path: '/abs/a.ts' })
     current = 's2'
-    await ws.openPath('/abs/b.ts')
+    await service.openWorkspacePath({ path: '/abs/b.ts' })
     expect(d.sidebar).toEqual(['s1:/abs/a.ts', 's2:/abs/b.ts'])
     restore()
   })
 
-  it('restores the original method on dispose (HMR-safe)', async () => {
-    const ws = service()
+  it('routes the folder-reveal gesture to the explorer, not the editor', async () => {
+    const opened: string[] = []
+    const service = fakeNamespaceService(opened)
     const d = deps()
-    const original = ws.openPath
-    const restore = wrapOpenPath(ws, d)
-    expect(ws.openPath).not.toBe(original)
+    const restore = wrapOpenWorkspacePath(service, d)
+    for (const path of ['.', './', '/w/.', 'C:\\w\\.']) {
+      await service.openWorkspacePath({ path })
+    }
+    expect(opened).toEqual([])
+    expect(d.sidebar).toEqual([])
+    expect(d.revealed).toEqual(['s1:.', 's1:./', 's1:/w/.', 's1:C:\\w\\.'])
     restore()
-    expect(ws.openPath).toBe(original)
-    await ws.openPath('/abs/a.ts')
-    expect(ws.opened).toEqual(['/abs/a.ts'])
   })
 
-  it('treats a rejected promise like the original would (no swallowing)', async () => {
-    const failing: OpenPathService = {
-      async openPath() { throw new Error('host refused') },
-    }
+  it('restores the original accessor on dispose (HMR-safe)', async () => {
+    const opened: string[] = []
+    const service = fakeNamespaceService(opened)
+    const before = Object.getOwnPropertyDescriptor(service, 'openWorkspacePath')
+    expect(typeof before?.get).toBe('function')
+    const d = deps()
+    const restore = wrapOpenWorkspacePath(service, d)
+    // While wrapped, the property is our data-property shadow.
+    const during = Object.getOwnPropertyDescriptor(service, 'openWorkspacePath')
+    expect(during?.get).toBeUndefined()
+    expect(typeof during?.value).toBe('function')
+    restore()
+    const after = Object.getOwnPropertyDescriptor(service, 'openWorkspacePath')
+    expect(typeof after?.get).toBe('function')
+    await service.openWorkspacePath({ path: '/abs/a.ts' })
+    expect(opened).toEqual(['/abs/a.ts'])
+    expect(d.sidebar).toEqual([])
+  })
+
+  it('propagates a rejection from the original (no swallowing)', async () => {
+    const target = {} as Record<string, unknown>
+    Object.defineProperty(target, 'openWorkspacePath', {
+      configurable: true,
+      enumerable: true,
+      get: () => async () => { throw new Error('host refused') },
+    })
+    const service = target as unknown as OpenWorkspacePathService
     const d = deps({ takeoverEnabled: () => false })
-    const restore = wrapOpenPath(failing, d)
-    await expect(failing.openPath('/abs/a.ts')).rejects.toThrow('host refused')
+    const restore = wrapOpenWorkspacePath(service, d)
+    await expect(service.openWorkspacePath({ path: '/abs/a.ts' })).rejects.toThrow('host refused')
+    restore()
+  })
+
+  it('declines to wrap when the method is not installed (hand-rolled composition)', async () => {
+    const service = {} as OpenWorkspacePathService
+    const d = deps()
+    const restore = wrapOpenWorkspacePath(service, d)
+    expect(service.openWorkspacePath).toBeUndefined()
+    expect(d.sidebar).toEqual([])
     restore()
   })
 })
 
+describe('isFolderRevealPath', () => {
+  it('recognizes the dot gestures on both separator styles', () => {
+    expect(isFolderRevealPath('.')).toBe(true)
+    expect(isFolderRevealPath('./')).toBe(true)
+    expect(isFolderRevealPath('/w/.')).toBe(true)
+    expect(isFolderRevealPath('/w/./')).toBe(true)
+    expect(isFolderRevealPath('C:\\w\\.')).toBe(true)
+    expect(isFolderRevealPath('/w/a.ts')).toBe(false)
+    expect(isFolderRevealPath('/w/.hidden')).toBe(false)
+  })
+})
+
 describe('open-path interception wiring', () => {
-  it('registerOpenPathInterception routes chat opens into the editor tab and restores on dispose', async () => {
-    // A realistic client-context fake: the sessions list feed (current + cwd),
-    // the workspaces funnel, and the sidebar service the editor goes through.
-    const opened: Array<Record<string, unknown>> = []
-    const funnel = { openPath: async (): Promise<void> => {} }
+  /**
+   * A client-context fake whose `inject` mimics cordis: the callback runs
+   * once the dependency appears (here: when `mount()` is called) and its
+   * effects dispose with the fiber.
+   */
+  function fakeCtx(opened: Array<Record<string, unknown>>, remoteSession: OpenWorkspacePathService) {
+    let effectDisposer: (() => void) | undefined
+    let injectCallback: ((fctx: unknown) => void) | undefined
+    const fctx = {
+      get: (name: string) => (name === 'remote.session' ? remoteSession : undefined),
+      effect: (fn: () => () => void) => { effectDisposer = fn() },
+    }
     const ctx = {
       sessions: {
         list: { getSnapshot: () => ({ current: 's1', byId: { s1: { cwd: '/w' } } }) },
       },
-      workspaces: funnel,
-      betterSidebar: { openTab: (seed: unknown) => { opened.push(seed as Record<string, unknown>) } },
       get: (name: string) => name === 'betterSidebar'
         ? { openTab: (seed: unknown) => { opened.push(seed as Record<string, unknown>) } }
         : undefined,
-    } as unknown as Context
+      inject: (_deps: string[], callback: (fctx: unknown) => void) => {
+        injectCallback = callback
+        return {
+          dispose: async () => { effectDisposer?.() },
+        }
+      },
+      /** Test helper: simulate the namespace service appearing. */
+      mount: () => { injectCallback?.(fctx) },
+    }
+    return ctx
+  }
+
+  it('registers through ctx.inject and routes chat opens into the editor tab', async () => {
+    const opened: Array<Record<string, unknown>> = []
+    const hostOpened: string[] = []
+    const remoteSession = fakeNamespaceService(hostOpened)
+    const ctx = fakeCtx(opened, remoteSession)
     const store = createSidebarStore()
-    const original = ctx.workspaces.openPath
-    const restore = registerOpenPathInterception(ctx, store)
+    const restore = registerOpenPathInterception(ctx as unknown as Context, store)
+
+    // Before the namespace mounts, nothing is wrapped.
+    expect(Object.getOwnPropertyDescriptor(remoteSession, 'openWorkspacePath')?.get).toBeDefined()
+    ctx.mount()
 
     // Default prefs: the takeover routes the open into the sidebar editor
     // with the session-scoped absolute path (chat already resolved it).
-    await ctx.workspaces.openPath('/w/src/a.ts')
+    await remoteSession.openWorkspacePath({ path: '/w/src/a.ts' })
     expect(opened).toEqual([{
       type: 'editor',
       title: 'a.ts',
       path: '/w/src/a.ts',
       id: 'editor:/w/src/a.ts',
     }])
+    expect(hostOpened).toEqual([])
 
     // The interceptOpenPath pref off → the original funnel runs untouched.
     store.setPrefs({ ...store.getPrefs(), interceptOpenPath: false })
-    const calls: string[] = []
-    ctx.workspaces.openPath = async (path: string) => { calls.push(path) }
-    await ctx.workspaces.openPath('/w/src/b.ts')
-    expect(calls).toEqual(['/w/src/b.ts'])
+    await remoteSession.openWorkspacePath({ path: '/w/src/b.ts' })
+    expect(hostOpened).toEqual(['/w/src/b.ts'])
     expect(opened).toHaveLength(1)
 
     // The editor tab disabled → falls through too (an editor that cannot
     // open must not swallow opens).
     store.setPrefs({ ...store.getPrefs(), interceptOpenPath: true, tabsEnabled: { editor: false } })
-    await ctx.workspaces.openPath('/w/src/c.ts')
-    expect(calls).toEqual(['/w/src/b.ts', '/w/src/c.ts'])
+    await remoteSession.openWorkspacePath({ path: '/w/src/c.ts' })
+    expect(hostOpened).toEqual(['/w/src/b.ts', '/w/src/c.ts'])
 
-    // Disposal restores the raw original method (HMR-safe).
+    // Disposal restores the accessor (HMR-safe).
     restore()
-    expect(ctx.workspaces.openPath).toBe(original)
+    const descriptor = Object.getOwnPropertyDescriptor(remoteSession, 'openWorkspacePath')
+    expect(typeof descriptor?.get).toBe('function')
+  })
+
+  it('re-applies the shadow when the namespace service is remounted', async () => {
+    const opened: Array<Record<string, unknown>> = []
+    const hostOpened: string[] = []
+    // A ctx whose inject can fire multiple times (service recreate).
+    let effectDisposer: (() => void) | undefined
+    let injectCallback: ((fctx: unknown) => void) | undefined
+    let current = fakeNamespaceService(hostOpened)
+    const ctx = {
+      sessions: { list: { getSnapshot: () => ({ current: 's1', byId: { s1: { cwd: '/w' } } }) } },
+      get: (name: string) => name === 'betterSidebar'
+        ? { openTab: (seed: unknown) => { opened.push(seed as Record<string, unknown>) } }
+        : undefined,
+      inject: (_deps: string[], callback: (fctx: unknown) => void) => {
+        injectCallback = callback
+        return { dispose: async () => { effectDisposer?.() } }
+      },
+      remount: () => {
+        effectDisposer?.()
+        current = fakeNamespaceService(hostOpened)
+        injectCallback?.({
+          get: (name: string) => (name === 'remote.session' ? current : undefined),
+          effect: (fn: () => () => void) => { effectDisposer = fn() },
+        })
+      },
+    }
+    const store = createSidebarStore()
+    registerOpenPathInterception(ctx as unknown as Context, store)
+    ctx.remount()
+    await current.openWorkspacePath({ path: '/w/src/a.ts' })
+    expect(opened).toHaveLength(1)
+    // A remount (dispose + fresh service) must not leak the old shadow and
+    // must wrap the fresh instance.
+    ctx.remount()
+    await current.openWorkspacePath({ path: '/w/src/b.ts' })
+    expect(opened).toHaveLength(2)
+    expect(hostOpened).toEqual([])
   })
 })