diff --git a/config/tsconfig.cli.json b/config/tsconfig.cli.json
index 681a8c1ea14..471cebc5b02 100644
--- a/config/tsconfig.cli.json
+++ b/config/tsconfig.cli.json
@@ -238,6 +238,7 @@
     "../src/main/openclaude/hook-service.ts",
     "../src/main/rolling-file-backup.ts",
     "../src/main/startup/hydrate-shell-path.ts",
+    "../src/main/startup/shell-path-probe.ts",
     "../src/main/startup/windows-shell-path-ownership.ts",
     // Why: serve-electron-flag-parity.test.ts checks the Electron-side serve argv rewrite against this
     // project's serve spec; the module has no imports, so listing it pulls in nothing else.
diff --git a/src/main/startup/hydrate-shell-path.test.ts b/src/main/startup/hydrate-shell-path.test.ts
index b2e40ab8709..f09b965486f 100644
--- a/src/main/startup/hydrate-shell-path.test.ts
+++ b/src/main/startup/hydrate-shell-path.test.ts
@@ -210,6 +210,52 @@ describe('hydrateShellPath', () => {
     expect((await captureProbeEnv()).ORCA_SHELL_PATH_PROBE).toBe('1')
   })
 
+  // Why: on Windows the probe is PowerShell or Git Bash, so these argv are never produced.
+  it.skipIf(process.platform === 'win32').each(['/bin/bash', '/bin/zsh'])(
+    'keeps the POSIX login probe for %s',
+    async (shell) => {
+      await captureProbeEnv(shell)
+
+      expect(spawnMock.mock.calls[0][1]).toEqual([
+        '-ilc',
+        `printf '%s' '__ORCA_SHELL_PATH__'; printf '%s' "$PATH"; printf '%s' '__ORCA_SHELL_PATH__'`
+      ])
+    }
+  )
+
+  it.skipIf(process.platform === 'win32')(
+    'reads Nushell PATH while preserving interactive login configuration',
+    async () => {
+      const proc = createMockShellProcess()
+      spawnMock.mockReturnValue(proc)
+      const resultPromise = hydrateShellPath({
+        shellOverride: '/run/current-system/sw/bin/nu',
+        force: true
+      })
+      await vi.waitFor(() => expect(spawnMock).toHaveBeenCalled())
+
+      expect(spawnMock.mock.calls[0][1]).toEqual([
+        '-ilc',
+        [
+          "print -n '__ORCA_SHELL_PATH__';",
+          'print -n ($env.PATH | str join (char esep));',
+          "print -n '__ORCA_SHELL_PATH__'"
+        ].join(' ')
+      ])
+      proc.stdout.emit(
+        'data',
+        Buffer.from('__ORCA_SHELL_PATH__/etc/profiles/per-user/me/bin:/usr/bin__ORCA_SHELL_PATH__')
+      )
+      proc.emit('close', 0)
+
+      await expect(resultPromise).resolves.toEqual({
+        segments: ['/etc/profiles/per-user/me/bin', '/usr/bin'],
+        ok: true,
+        failureReason: 'none'
+      })
+    }
+  )
+
   it('overwrites the captured key in place so Windows never carries both Path and PATH', async () => {
     vi.spyOn(process, 'platform', 'get').mockReturnValue('win32')
     const originalWindowsPath = process.env.Path
diff --git a/src/main/startup/hydrate-shell-path.ts b/src/main/startup/hydrate-shell-path.ts
index a109b6e61ec..73f48b512b9 100644
--- a/src/main/startup/hydrate-shell-path.ts
+++ b/src/main/startup/hydrate-shell-path.ts
@@ -2,6 +2,7 @@ import { spawn } from 'node:child_process'
 import { delimiter, win32 as pathWin32 } from 'node:path'
 import type { ShellHydrationFailureReason } from '../../shared/shell-path-hydration-types'
 import { resolveWindowsShellStartupFamily } from '../../shared/windows-terminal-shell'
+import { SHELL_PATH_DELIMITER as DELIMITER, shellPathProbe } from './shell-path-probe'
 import { WindowsShellPathOwnership, createWindowsPathKey } from './windows-shell-path-ownership'
 
 // Why: GUI-launched Electron can miss PATH entries added by shell profiles.
@@ -11,7 +12,6 @@ import { WindowsShellPathOwnership, createWindowsPathKey } from './windows-shell
 //
 // Probe the profile-loading shell once instead of hard-coding every tool's install path.
 
-const DELIMITER = '__ORCA_SHELL_PATH__'
 // Why 10s: 5s was chosen without measurement and a real profile overruns it —
 // a bash -ilc loading nvm, rvm, conda and gcloud measures ~1s idle but 6-7s on a
 // loaded machine, so a cold start under load silently fell back to the seeded
@@ -179,24 +179,7 @@ export function runWithLaunchPath<T>(action: () => T): T {
   }
 }
 
-function shellPathProbe(shell: string): { args: string[]; pathDelimiter: string } {
-  if (process.platform !== 'win32') {
-    const command = `printf '%s' '${DELIMITER}'; printf '%s' "$PATH"; printf '%s' '${DELIMITER}'`
-    return { args: ['-ilc', command], pathDelimiter: delimiter }
-  }
-  if (resolveWindowsShellStartupFamily(shell) === 'posix') {
-    // Why: native child processes cannot resolve Git Bash's /c/... PATH entries.
-    const command = `printf '%s' '${DELIMITER}'; cygpath -wp "$PATH"; printf '%s' '${DELIMITER}'`
-    return { args: ['-ilc', command], pathDelimiter: ';' }
-  }
-  const command =
-    `[Console]::OutputEncoding = [System.Text.UTF8Encoding]::new($false); ` +
-    `[Console]::Write('${DELIMITER}'); [Console]::Write($env:Path); ` +
-    `[Console]::Write('${DELIMITER}')`
-  // Why: omitting -NoProfile is the behavior this probe exists to capture.
-  return { args: ['-NoLogo', '-Command', command], pathDelimiter: ';' }
-}
-
+/** Capture the login PATH without profile banners. */
 function spawnShellAndReadPath(shell: string): Promise<HydrationResult> {
   return new Promise((resolve) => {
     // Why: delimiters isolate PATH from profile banners and MOTDs.
diff --git a/src/main/startup/shell-path-probe.ts b/src/main/startup/shell-path-probe.ts
new file mode 100644
index 00000000000..20461dbe617
--- /dev/null
+++ b/src/main/startup/shell-path-probe.ts
@@ -0,0 +1,37 @@
+import { delimiter, win32 as pathWin32 } from 'node:path'
+import { resolveWindowsShellStartupFamily } from '../../shared/windows-terminal-shell'
+
+export const SHELL_PATH_DELIMITER = '__ORCA_SHELL_PATH__'
+
+/** Build the login PATH probe in the selected shell's native syntax. */
+export function shellPathProbe(shell: string): { args: string[]; pathDelimiter: string } {
+  if (process.platform !== 'win32') {
+    if (pathWin32.basename(shell).toLowerCase() === 'nu') {
+      // Why: Nushell's PATH is a list; POSIX "$PATH" prints a literal instead.
+      const command = [
+        `print -n '${SHELL_PATH_DELIMITER}';`,
+        'print -n ($env.PATH | str join (char esep));',
+        `print -n '${SHELL_PATH_DELIMITER}'`
+      ].join(' ')
+      // Why: existing interactive login flags preserve $nu.is-interactive configuration.
+      return { args: ['-ilc', command], pathDelimiter: delimiter }
+    }
+    const command =
+      `printf '%s' '${SHELL_PATH_DELIMITER}'; printf '%s' "$PATH"; ` +
+      `printf '%s' '${SHELL_PATH_DELIMITER}'`
+    return { args: ['-ilc', command], pathDelimiter: delimiter }
+  }
+  if (resolveWindowsShellStartupFamily(shell) === 'posix') {
+    // Why: native child processes cannot resolve Git Bash's /c/... PATH entries.
+    const command =
+      `printf '%s' '${SHELL_PATH_DELIMITER}'; cygpath -wp "$PATH"; ` +
+      `printf '%s' '${SHELL_PATH_DELIMITER}'`
+    return { args: ['-ilc', command], pathDelimiter: ';' }
+  }
+  const command =
+    `[Console]::OutputEncoding = [System.Text.UTF8Encoding]::new($false); ` +
+    `[Console]::Write('${SHELL_PATH_DELIMITER}'); [Console]::Write($env:Path); ` +
+    `[Console]::Write('${SHELL_PATH_DELIMITER}')`
+  // Why: omitting -NoProfile is the behavior this probe exists to capture.
+  return { args: ['-NoLogo', '-Command', command], pathDelimiter: ';' }
+}