diff --git a/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.i18n.yaml b/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.i18n.yaml
new file mode 100644
index 0000000000..8621e073de
--- /dev/null
+++ b/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.i18n.yaml
@@ -0,0 +1,6 @@
+# Bilingual-pair consistency record (docs/i18n/README.md): the git blob hash of each
+# 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/bug-fix/2026-08-19-win32-dialog-worker-source-launch.md
+2026-08-19-win32-dialog-worker-source-launch.md: 44eb6634d44c7338bae7ac90c5f50aecfa142bd2
+2026-08-19-win32-dialog-worker-source-launch.zh.md: 9055289fa40a914f6506064b63388520352cf29d
diff --git a/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.md b/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.md
new file mode 100644
index 0000000000..44eb6634d4
--- /dev/null
+++ b/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.md
@@ -0,0 +1,74 @@
+# Agent Note: Win32 dialog worker source launch drops the tsx bootstrap
+
+Status: implemented
+
+English | [中文](2026-08-19-win32-dialog-worker-source-launch.zh.md)
+
+## Problem
+
+On Windows, the source-plane folder dialog worker never started: the Web UI reported `win32 folder dialog worker exited before reporting a result`. The failure was in the launch vector, not koffi: the source arm ran `node --import tsx/esm <absolute .ts path>`. With a loader registered through `--import`, an absolute path such as `E:\dsh\packages\host\directory-picker-native\src\win32-dialog-worker.ts` can be read as an `e:` scheme URL and rejected with `ERR_UNSUPPORTED_ESM_URL_SCHEME`, before the worker posts its first IPC message. The registered entry is what differs from this repository's other absolute-path launches: they register the full `tsx` entry (`packages/test-support/loader-smoke/src/index.ts`) and pass on Windows CI, while this arm registered the ESM-only `tsx/esm` hook.
+
+A raw `import.meta.url.endsWith('.ts')` check also decided which arm to launch. Vitest and Vite may decorate a module URL with a query string, and a decorated URL fails that suffix test, so a source-plane test could exercise the built arm — a bundler-specific test hazard rather than a cause of the Windows failure.
+
+## Decision
+
+Run the source worker directly under Node's native type stripping:
+
+```ts
+import { spawn } from 'node:child_process'
+import { fileURLToPath } from 'node:url'
+
+declare const env: NodeJS.ProcessEnv
+spawn(process.execPath, [fileURLToPath(new URL('./win32-dialog-worker.ts', import.meta.url))], { env, windowsHide: true })
+```
+
+The repository requires `^22.19.0 || >=24.0.0`, and this worker dependency graph is package-local: the worker, bindings, and logic modules import no workspace packages, so no tsconfig `paths` projection is needed.
+
+Every relative import that names a type is marked, with `import type` or the inline `type` modifier. `tsconfig.base.json` sets `verbatimModuleSyntax: false`, so an unmarked type import is elided at build time and passes both `typecheck` and the bundle, while Node strip mode keeps the specifier and fails at load with `does not provide an export named`. Marking is mandatory here even though no compiler or lint rule demands it.
+
+`packages/code-runtime/code-runtime-worker-thread/src/index.ts` already loads its source worker this way under the same two preconditions, and [the test-subprocess launch modes](../../../../docs/testing.md#test-subprocess-launch-modes) permit erasable `.ts` subprocesses to run directly with Node without tsx or the root paths map.
+
+The packaged arm remains `worker.cjs` under plain node. Both arms choose from `new URL(import.meta.url).pathname.endsWith('.ts')`, so a query string on the module URL cannot misclassify a source module as built.
+
+Neither precondition has a static gate; the real worker launch enforces both. A construct strip mode refuses — a value `enum`, a `namespace` with runtime members, a parameter property, a decorator — or a type import left unmarked, makes Node reject the entry before the worker posts, which surfaces as the worker-exit rejection instead of the expected Win32 dialog error.
+
+## Inherited NODE_OPTIONS
+
+A source worker inherits `NODE_OPTIONS` from the host, and either spelling that disables native type stripping across the supported Node range is removed from the child environment:
+
+- `--no-experimental-strip-types`
+- `--no-strip-types`
+
+Every other entry is preserved, and an options string that carried only disable flags leaves the variable unset in the child. Sanitization is scoped to the source arm: the packaged `worker.cjs` arm has no native type-stripping dependency, so its inherited options pass through untouched.
+
+An inherited `--import` is preserved like any other entry, so a host that registers a loader process-wide puts the `e:` scheme hazard back in front of the worker path. This launch cannot tell an instrumentation hook from a TypeScript one, so that case stays the host's to avoid.
+
+## Related launch paths
+
+The `dsh` CLI source launch keeps the tsx ESM hook because its graph needs a transform mode Node no longer ships, per [the source-launch decision](../architecture/2026-07-29-dsh-source-launch-tsx-esm.md); that constraint is about the CLI graph, not about native stripping being unavailable in the engines range.
+
+`packages/sandbox/sandbox-local/src/index.ts` still builds this vector — the same ESM-only `tsx/esm` hook in front of an absolute path — for the windows-acl runner's source arm, and that graph is package-local and erasable too, so the same launch applies there. It is a separate change: it also rewrites the assertion in `packages/sandbox/sandbox-local/tests/local.spec.ts` that pins the `--import tsx/esm` prefix.
+
+`packages/workflow/workflow-worker-thread/src/host.ts` selects its own source/built arm from the raw `import.meta.url`, but it boots the worker from a `data:` URL carrying a proper `file://` href, so the `e:` scheme failure cannot reach that launch. Its raw check does leave the query-string hazard: on a built tree a decorated URL selects `worker.cjs`, so a source-plane test there can exercise built code — which artifact a test covers, not a production launch.
+
+## Alternatives considered
+
+**Pass the worker as a `file://` URL instead of a path.** Rejected: tsx's tsconfig-paths hook mangles `file://` URLs into `<cwd>\file:\<path>` (`ERR_MODULE_NOT_FOUND`); keeping any tsx involvement leaves a fragile launch.
+
+**Probe koffi availability and fall back to pure-Node dialogs.** Out of scope: the lockfile resolves koffi to 3.1.1, and the worker crashed before koffi ever loaded, so koffi is not the failure on this codebase.
+
+**Pass an explicit enabling flag to the child instead of sanitizing `NODE_OPTIONS`.** Rejected: Node has already renamed this feature's negation once (`--no-experimental-strip-types`, then `--no-strip-types`), so a hardcoded enabling flag couples the launch to a Node line, while removing both known disable spellings works across the engines range.
+
+## Consequences
+
+- Windows source launches (`pnpm dsh web`) run the worker directly under Node's native type stripping, so no loader chain can read the worker path as an `e:` scheme URL.
+- Packaged hosts keep the unchanged CJS worker arm and an untouched `NODE_OPTIONS`.
+- The source arm depends on the engines range, a package-local erasable-only graph, marked type imports, and removal of inherited type-stripping disable flags; [the package README](../../../../packages/host/directory-picker-native/README.md) states those preconditions for consumers.
+- The Win32 smoke reaches the real source launch even where a module runner decorates URLs with query strings.
+
+## Verification
+
+- `packages/host/directory-picker-native/tests/win32-dialog-host.spec.ts` pins the source launch: `process.execPath` runs the worker path as the sole positional argument, with no loader flag.
+- The same suite covers the three `NODE_OPTIONS` cases — a mixed string keeps its unrelated entries and leaves the parent untouched, a string of only disable flags leaves the variable unset, and an unset variable stays unset.
+- `tests/win32-dialog.spec.ts` launches the real source worker on POSIX. A non-erasable construct or an unmarked type import makes that launch exit before reporting, so the test fails on the worker-exit rejection instead of the expected `win32 folder dialog failed`.
+- On win32 the same suite opens and abort-closes a real dialog through the source arm; `tests/built-worker.e2e.ts` owns the packaged `worker.cjs` arm this decision leaves unchanged.
diff --git a/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.zh.md b/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.zh.md
new file mode 100644
index 0000000000..9055289fa4
--- /dev/null
+++ b/.agents/notes/implemented/bug-fix/2026-08-19-win32-dialog-worker-source-launch.zh.md
@@ -0,0 +1,74 @@
+# Agent Note: Win32 对话框 worker 源码启动去掉 tsx 引导
+
+Status: implemented
+
+[English](2026-08-19-win32-dialog-worker-source-launch.md) | 中文
+
+## 问题
+
+Windows 上源码面的文件夹对话框 worker 从未启动成功：Web UI 只报出 `win32 folder dialog worker exited before reporting a result`。故障出在启动向量而非 koffi：源码分支运行的是 `node --import tsx/esm <绝对路径 .ts>`。通过 `--import` 注册 loader 后，像 `E:\dsh\packages\host\directory-picker-native\src\win32-dialog-worker.ts` 这样的绝对路径可能被读作 `e:` scheme URL 并以 `ERR_UNSUPPORTED_ESM_URL_SCHEME` 拒绝，此时 worker 还没发出第一条 IPC 消息。与仓库中其他「绝对路径」启动的区别在于注册的入口：它们注册的是完整的 `tsx` 入口（`packages/test-support/loader-smoke/src/index.ts`），在 Windows CI 上是绿的，而这个分支注册的是仅 ESM 的 `tsx/esm` hook。
+
+决定启动哪个分支的判断此前读的是裸 `import.meta.url`。Vitest 与 Vite 可能给模块 URL 附加查询串，带查询串的 URL 通不过这个后缀判断，于是源码面的测试可能跑到 built 分支上——这属于 bundler 测试环境的风险，而不是 Windows 故障的成因。
+
+## 决策
+
+源码 worker 直接由 Node 原生类型剥离运行：
+
+```ts
+import { spawn } from 'node:child_process'
+import { fileURLToPath } from 'node:url'
+
+declare const env: NodeJS.ProcessEnv
+spawn(process.execPath, [fileURLToPath(new URL('./win32-dialog-worker.ts', import.meta.url))], { env, windowsHide: true })
+```
+
+仓库 engines 要求 `^22.19.0 || >=24.0.0`，且该 worker 的依赖图是包内闭合的：worker、bindings、logic 三个模块都不导入 workspace 包，因此不需要 tsconfig `paths` 投射。
+
+凡是命名类型的相对导入都必须标注，用 `import type` 或行内 `type` 修饰符。`tsconfig.base.json` 设置了 `verbatimModuleSyntax: false`，未标注的类型导入会在构建时被消除，`typecheck` 与打包都不会报错，而 Node 剥离模式会保留该导入并在加载时以 `does not provide an export named` 失败。因此即使没有任何编译器或 lint 规则强制，这里也必须标注。
+
+`packages/code-runtime/code-runtime-worker-thread/src/index.ts` 已经在同样这两个前提下以这种方式加载它的源码 worker，[测试子进程启动方式](../../../../docs/testing.md#test-subprocess-launch-modes)也允许可擦除的 `.ts` 子进程直接由 Node 运行，不经 tsx 或根路径映射。
+
+打包分支继续由纯 node 启动 `worker.cjs`。两个分支都由 `new URL(import.meta.url).pathname.endsWith('.ts')` 选择，模块 URL 上的查询串无法把源码模块误判为构建产物。
+
+这两个前提都没有静态门禁，由真实 worker 启动来保证。出现剥离模式拒绝的语法——value `enum`、带运行时成员的 `namespace`、参数属性、装饰器——或有类型导入漏了标注，Node 会在 worker 上报之前拒绝入口，表现为 worker 退出类拒绝，而不是预期中的 Win32 对话框错误。
+
+## 继承的 NODE_OPTIONS
+
+源码 worker 会继承宿主的 `NODE_OPTIONS`，支持的 Node 范围内两种关闭原生类型剥离的写法都会从子进程环境中移除：
+
+- `--no-experimental-strip-types`
+- `--no-strip-types`
+
+其余条目全部保留；若整串只有这些禁用 flag，子进程中该变量为未设置。清理只作用于源码分支：打包后的 `worker.cjs` 分支没有原生类型剥离依赖，其继承的选项原样透传。
+
+继承而来的 `--import` 同样会被保留，因此在进程级注册 loader 的宿主会把 `e:` scheme 风险重新放回 worker 路径之前。本启动无法区分插桩 hook 与 TypeScript hook，这种情况仍需宿主自行规避。
+
+## 相关启动路径
+
+`dsh` CLI 的源码启动保留 tsx ESM hook，因为它的源码图需要 Node 已不再提供的 transform 模式，见[源码启动决策](../architecture/2026-07-29-dsh-source-launch-tsx-esm.md)；那条约束针对的是 CLI 源码图，而不是说 engines 范围内没有原生剥离。
+
+`packages/sandbox/sandbox-local/src/index.ts` 仍在为 windows-acl runner 的源码分支拼出同一个启动向量——同样是仅 ESM 的 `tsx/esm` hook 加绝对路径，而那个源码图同样包内闭合且可擦除，因此同样的启动方式适用。它属于独立改动：一并要改写 `packages/sandbox/sandbox-local/tests/local.spec.ts` 中钉住 `--import tsx/esm` 前缀的断言。
+
+`packages/workflow/workflow-worker-thread/src/host.ts` 同样从裸 `import.meta.url` 选择源码/构建分支，但它的 worker 从携带正确 `file://` href 的 `data:` URL 启动，`e:` scheme 故障触及不到那条启动路径。它的裸判断确实留下了查询串风险：在已构建的树上，带查询串的 URL 会选中 `worker.cjs`，于是那里的源码面测试可能跑到构建产物上——这影响测试覆盖的是哪个产物，而非生产启动。
+
+## 考虑过的替代方案
+
+**把 worker 作为 `file://` URL 而不是路径传入。** 拒绝：tsx 的 tsconfig-paths hook 会把 `file://` URL 改写成 `<cwd>\file:\<path>`（`ERR_MODULE_NOT_FOUND`）；只要还牵扯 tsx，启动就是脆弱的。
+
+**探测 koffi 可用性并回退到纯 Node 对话框。** 超出范围：锁文件把 koffi 解析到 3.1.1，而 worker 在 koffi 加载之前就已崩溃，因此 koffi 并非本代码库的故障点。
+
+**给子进程显式传入开启 flag，而不是清理 `NODE_OPTIONS`。** 拒绝：Node 已经把该特性的否定写法改过一次（先是 `--no-experimental-strip-types`，后为 `--no-strip-types`），硬编码开启 flag 会把启动绑定到某条 Node 线，而移除两种已知的禁用写法在整个 engines 范围内都成立。
+
+## 后果
+
+- Windows 源码启动（`pnpm dsh web`）直接由 Node 原生类型剥离运行 worker，不再有任何 loader 链会把 worker 路径读成 `e:` scheme URL。
+- 打包宿主保持不变的 CJS worker 分支，`NODE_OPTIONS` 不被改写。
+- 源码分支依赖 engines 范围、包内闭合且只含可擦除语法的依赖图、标注过的类型导入，以及移除继承的类型剥离禁用 flag；[包 README](../../../../packages/host/directory-picker-native/README.md) 为使用者写明了这些前提。
+- 即使模块运行器给 URL 附加查询串，Win32 冒烟测试也能进入真实的源码启动。
+
+## 验证
+
+- `packages/host/directory-picker-native/tests/win32-dialog-host.spec.ts` 钉住源码启动：由 `process.execPath` 以唯一位置参数运行 worker 路径，不带任何 loader flag。
+- 同一套件覆盖 `NODE_OPTIONS` 的三种场景——混合串保留无关条目且不改动父进程、只含禁用 flag 的串使该变量为未设置、未设置时保持未设置。
+- `tests/win32-dialog.spec.ts` 在 POSIX 上启动真实源码 worker。出现不可擦除语法或未标注的类型导入时，该启动会在上报前退出，于是测试以 worker 退出类拒绝失败，而不是预期的 `win32 folder dialog failed`。
+- 在 win32 上，同一套件通过源码分支真实打开并中止关闭对话框；`tests/built-worker.e2e.ts` 负责本决策未改动的打包 `worker.cjs` 分支。
diff --git a/AGENTS.md b/AGENTS.md
index 53f4d17bdb..f83385ad28 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -98,7 +98,7 @@ Real-API tests and demos read `DEEPSEEK_API_KEY`, optional `DEEPSEEK_BASE_URL`,
 ## Conventions
 
 - Every npm package is `@deepseek-ai/dsh-<name>`; vendored packages are rescoped ([mapping](docs/rescope.md)) and `private: true`. `@deepseek-ai/cordis` is a peerDependency (+ dev) of every harness package.
-- ESM everywhere (`"type": "module"`). Use package names across packages and `.ts` in local relative imports. Config subprocesses run built `lib/` under plain Node; source regressions use their declared launcher ([testing policy](docs/testing.md#test-subprocess-launch-modes)). The `dsh` CLI source launch runs through tsx's ESM-only hook (`node --import tsx/esm`); modules it reaches must stay ESM (no CJS-only exports) — Node's native TypeScript modes are unavailable across the engines range ([source-launch contract](.agents/notes/implemented/architecture/2026-07-29-dsh-source-launch-tsx-esm.md)). Raw/Web `cordis.yml` bare plugins must appear in their resolver manifest's `dependencies`; `verify-cordis-config` enforces it.
+- ESM everywhere (`"type": "module"`). Use package names across packages and `.ts` in local relative imports. Config subprocesses run built `lib/` under plain Node; source regressions use their declared launcher ([testing policy](docs/testing.md#test-subprocess-launch-modes)). The `dsh` CLI source launch runs through tsx's ESM-only hook (`node --import tsx/esm`); modules it reaches must stay ESM (no CJS-only exports) — Node's native transform mode is gone and its strip mode rejects that graph's syntax ([source-launch contract](.agents/notes/implemented/architecture/2026-07-29-dsh-source-launch-tsx-esm.md)). Raw/Web `cordis.yml` bare plugins must appear in their resolver manifest's `dependencies`; `verify-cordis-config` enforces it.
 - **Registrations are effects**: every contribution goes through `ctx.effect()` / `ctx.on()`; a registry's `register()` returns the disposer.
 - **Runtime invariants assert owned relationships.** Check authoritative event streams or mutable data, not service or method presence, plugin metadata or effects, or fixed pure examples. Without a plausible relationship, an explained empty companion is correct ([package invariant rules](packages/AGENTS.md)).
 - **Typed events use declaration merging** and merge-extensible maps. Event JSDoc needs `@mode` and payload `@param`; scoped keys absent from payloads need `@dshScopeScan unsupported`. Public service methods document parameters and non-void returns. A `SessionEventMap` member is required-on-read by default — builds that do not know its type refuse the log unless the event carries the envelope's `ignorable: true`; only structural format changes bump `SESSION_FORMAT_VERSION` ([mechanism](.agents/notes/implemented/architecture/2026-08-10-session-log-version-mechanism.md)).
diff --git a/packages/host/directory-picker-native/README.i18n.yaml b/packages/host/directory-picker-native/README.i18n.yaml
index dc1cf3adab..3f1641b98d 100644
--- a/packages/host/directory-picker-native/README.i18n.yaml
+++ b/packages/host/directory-picker-native/README.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 packages/host/directory-picker-native/README.md
-README.md: 414dee8e0a064277dfd153196c17c780cb31bcb0
-README.zh.md: 3463f149d175ae9c2b95cc5eb25fe9b3762df902
+README.md: 7fa7fa630135587c193088371622790290e21a99
+README.zh.md: e881d96249322608d815d610ced439799ac2852e
diff --git a/packages/host/directory-picker-native/README.md b/packages/host/directory-picker-native/README.md
index 414dee8e0a..7fa7fa6301 100644
--- a/packages/host/directory-picker-native/README.md
+++ b/packages/host/directory-picker-native/README.md
@@ -18,3 +18,4 @@ None; this package neither assembles nor sends a provider request.
 
 - **Linux requires desktop tooling** — with neither Zenity nor KDialog installed, `pick` rejects with an actionable error; it does not fall back to a typed-path prompt (the browse backend is that fallback at the composition level).
 - **Windows has no mechanism fallback** — the child-process picker through packaged koffi is the only native tier, so a COM refusal or dialog crash surfaces the failure. The browse backend remains the fallback at the composition level.
+- **Windows source-plane launch depends on native TypeScript stripping** — Node executes the source worker directly on the repository engines range (`^22.19.0 || >=24.0.0`), so its package-local dependency graph must stay erasable TypeScript and every relative import that names a type must be marked (`import type` or the inline `type` modifier); an unmarked one compiles but fails at load. The source child also drops inherited `NODE_OPTIONS` entries that disable native type stripping (`--no-experimental-strip-types`, `--no-strip-types`), while every other entry is preserved — including an `--import` loader, which reintroduces the launch failure this backend works around. The packaged CJS worker has none of these source-plane dependencies.
diff --git a/packages/host/directory-picker-native/README.zh.md b/packages/host/directory-picker-native/README.zh.md
index 3463f149d1..e881d96249 100644
--- a/packages/host/directory-picker-native/README.zh.md
+++ b/packages/host/directory-picker-native/README.zh.md
@@ -18,3 +18,4 @@
 
 - **Linux 依赖桌面工具**——Zenity 与 KDialog 均未安装时，`pick` 以包含解决建议的错误拒绝；它不会回退为手输路径提示（组合层面的回退是 browse 后端）。
 - **Windows 没有机制级回退**——通过打包依赖 koffi 运行的子进程选择器是唯一原生层级，因此 COM 拒绝或对话框崩溃会直接上报失败。组合层面的回退仍是 browse 后端。
+- **Windows 源码面启动依赖原生 TypeScript 类型剥离**——Node 在仓库 engines 范围（`^22.19.0 || >=24.0.0`）内直接执行源码 worker，因此其包内闭合的依赖图必须保持可擦除 TypeScript，且凡是命名类型的相对导入都必须标注（`import type` 或行内 `type` 修饰符）；漏标注的导入能编译通过、却会在加载时失败。源码子进程还会移除继承而来的关闭原生类型剥离的 `NODE_OPTIONS` 条目（`--no-experimental-strip-types`、`--no-strip-types`），其余条目一律保留——包括 `--import` loader，而它会把本后端所规避的启动故障重新引入。打包后的 CJS worker 不含这些源码面依赖。
diff --git a/packages/host/directory-picker-native/package.json b/packages/host/directory-picker-native/package.json
index dcbaf930ea..68f2beb2d4 100644
--- a/packages/host/directory-picker-native/package.json
+++ b/packages/host/directory-picker-native/package.json
@@ -47,7 +47,6 @@
   },
   "devDependencies": {
     "@deepseek-ai/dsh-invariants": "workspace:^",
-    "@deepseek-ai/cordis": "workspace:^",
-    "tsx": "^4.19.2"
+    "@deepseek-ai/cordis": "workspace:^"
   }
 }
diff --git a/packages/host/directory-picker-native/src/win32-dialog-host.ts b/packages/host/directory-picker-native/src/win32-dialog-host.ts
index d4277b4aad..4366821544 100644
--- a/packages/host/directory-picker-native/src/win32-dialog-host.ts
+++ b/packages/host/directory-picker-native/src/win32-dialog-host.ts
@@ -11,25 +11,50 @@ import { spawn, type StdioOptions } from 'node:child_process'
 import { fileURLToPath } from 'node:url'
 import type { Win32DialogWorkerData } from './win32-dialog-worker.ts'
 
+const NODE_TYPE_STRIPPING_DISABLE_FLAGS = /(?:^|\s)--(?:no-experimental-strip-types|no-strip-types)(?=\s|$)/g
+
+/**
+ * Remove Node options that disable native TypeScript type stripping. The
+ * worker source plane relies on Node's native type stripping, and inherited
+ * NODE_OPTIONS can otherwise restore the same generic worker-exit failure.
+ */
+function sanitizeNodeOptions(value: string | undefined): string | undefined {
+  if (!value) return value
+  const sanitized = value
+    .replace(NODE_TYPE_STRIPPING_DISABLE_FLAGS, ' ')
+    .replace(/\s{2,}/g, ' ')
+    .trim()
+  return sanitized === '' ? undefined : sanitized
+}
+
 /**
  * Spawn the dialog child process. Built consumers launch the bundled CJS
  * entry next to this module under plain node; unbuilt (source) consumers
- * bootstrap tsx first, mirroring the dsh CLI's source launch. The dialog is
- * the child's first window, so Windows activates it without a foreground
- * call.
+ * run the worker directly under Node's native type stripping (stable since
+ * 22.18, covered by the engines range). That source arm requires a
+ * package-local graph whose every type-naming relative import is marked
+ * (`import type` or the inline `type` modifier): an unmarked one compiles
+ * and bundles, then fails at load under strip mode.
+ * The dialog is the child's first window, so Windows activates it without a
+ * foreground call.
  * @param data - the child payload (dialog title).
  * @returns the spawned child process.
  */
 export function spawnDialogWorker(data: Win32DialogWorkerData): ReturnType<typeof spawn> {
   // A packaged Electron host uses its branded application as process.execPath;
   // child-only Node mode bypasses application startup and its single-instance lock.
-  const env = { ...process.env, DSH_DIALOG_TITLE: data.title, ELECTRON_RUN_AS_NODE: '1' }
+  const baseEnv = { ...process.env, DSH_DIALOG_TITLE: data.title, ELECTRON_RUN_AS_NODE: '1' }
   const stdio: StdioOptions = ['ignore', 'inherit', 'inherit', 'ipc']
+  // Use pathname (not the raw URL): bundlers/tests may append query strings,
+  // which are not part of the source file extension.
   /* v8 ignore next 3 -- the built-output arm: tests always run unbuilt (src/) */
-  if (!import.meta.url.endsWith('.ts')) {
-    return spawn(process.execPath, [fileURLToPath(new URL('./worker.cjs', import.meta.url))], { env, stdio, windowsHide: true })
+  if (!new URL(import.meta.url).pathname.endsWith('.ts')) {
+    return spawn(process.execPath, [fileURLToPath(new URL('./worker.cjs', import.meta.url))], { env: baseEnv, stdio, windowsHide: true })
   }
-  return spawn(process.execPath, ['--import', import.meta.resolve('tsx/esm'), fileURLToPath(new URL('./win32-dialog-worker.ts', import.meta.url))], { env, stdio, windowsHide: true })
+  // `node <absolute .ts path>`: no loader hook is inserted before the path, so an
+  // absolute Windows path cannot be misparsed as an `e:` scheme URL.
+  const env = { ...baseEnv, NODE_OPTIONS: sanitizeNodeOptions(process.env.NODE_OPTIONS) }
+  return spawn(process.execPath, [fileURLToPath(new URL('./win32-dialog-worker.ts', import.meta.url))], { env, stdio, windowsHide: true })
 }
 
 export { closeThreadWindows } from './win32-dialog-bindings.ts'
diff --git a/packages/host/directory-picker-native/tests/win32-dialog-host.spec.ts b/packages/host/directory-picker-native/tests/win32-dialog-host.spec.ts
index c8f785f6c1..db5945be79 100644
--- a/packages/host/directory-picker-native/tests/win32-dialog-host.spec.ts
+++ b/packages/host/directory-picker-native/tests/win32-dialog-host.spec.ts
@@ -1,4 +1,5 @@
 import type { ChildProcess, SpawnOptions } from 'node:child_process'
+import { fileURLToPath } from 'node:url'
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 
 type SpawnWorker = (command: string, args: readonly string[], options: SpawnOptions) => ChildProcess
@@ -39,4 +40,39 @@ describe('spawnDialogWorker', () => {
     })
     expect(process.env.ELECTRON_RUN_AS_NODE).toBe('')
   })
+
+  it('removes inherited flags that disable native TypeScript stripping', () => {
+    vi.stubEnv('NODE_OPTIONS', '--max-old-space-size=256 --no-experimental-strip-types --trace-warnings --no-strip-types')
+
+    spawnDialogWorker({ title: 'NODE_OPTIONS guard' })
+
+    expect(spawnMock).toHaveBeenCalledOnce()
+    const options = spawnMock.mock.calls[0]?.[2]
+    expect(options?.env?.NODE_OPTIONS).toBe('--max-old-space-size=256 --trace-warnings')
+    expect(process.env.NODE_OPTIONS).toBe('--max-old-space-size=256 --no-experimental-strip-types --trace-warnings --no-strip-types')
+  })
+
+  it('drops NODE_OPTIONS entirely when it carried only the disabling flag', () => {
+    vi.stubEnv('NODE_OPTIONS', '--no-strip-types')
+
+    spawnDialogWorker({ title: 'NODE_OPTIONS sole-flag guard' })
+
+    expect(spawnMock.mock.calls[0]?.[2]?.env?.NODE_OPTIONS).toBeUndefined()
+  })
+
+  it('passes no NODE_OPTIONS when the host did not set one', () => {
+    vi.stubEnv('NODE_OPTIONS', undefined)
+
+    spawnDialogWorker({ title: 'NODE_OPTIONS unset guard' })
+
+    expect(spawnMock.mock.calls[0]?.[2]?.env?.NODE_OPTIONS).toBeUndefined()
+  })
+
+  it('launches the source worker under plain node with no loader flags', () => {
+    spawnDialogWorker({ title: 'Source-plane guard' })
+
+    expect(spawnMock).toHaveBeenCalledOnce()
+    expect(spawnMock.mock.calls[0]?.[0]).toBe(process.execPath)
+    expect(spawnMock.mock.calls[0]?.[1]).toEqual([fileURLToPath(new URL('../src/win32-dialog-worker.ts', import.meta.url))])
+  })
 })
diff --git a/packages/host/directory-picker-native/tests/win32-dialog.spec.ts b/packages/host/directory-picker-native/tests/win32-dialog.spec.ts
index 8e7d6951b8..99d4ed932a 100644
--- a/packages/host/directory-picker-native/tests/win32-dialog.spec.ts
+++ b/packages/host/directory-picker-native/tests/win32-dialog.spec.ts
@@ -145,8 +145,9 @@ describe('pickWin32Directory', () => {
     expect(close.mock.calls.length).toBeGreaterThan(10)
   })
 
-  // POSIX hosts exercise the REAL default plumbing end to end: the tsx-bootstrapped
-  // worker spawns, loads koffi, fails to load ole32.dll, and reports the error.
+  // POSIX hosts exercise the REAL default plumbing end to end: the source
+  // worker spawns under plain node with native type stripping (no tsx
+  // bootstrap), loads koffi, fails to load ole32.dll, and reports the error.
   it.skipIf(process.platform === 'win32')('rejects through the real worker where the Win32 surface is unavailable', async () => {
     await expect(pickWin32Directory(live())).rejects.toThrow('win32 folder dialog failed')
   }, 30_000)
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 2860dc4eb0..367b2fa516 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -5198,9 +5198,6 @@ importers:
       '@deepseek-ai/dsh-invariants':
         specifier: workspace:^
         version: link:../../runtime-diagnostics/invariants
-      tsx:
-        specifier: ^4.19.2
-        version: 4.22.4
 
   packages/host/frontend-static:
     dependencies: