fix: recover blocked native folder picker

src-tauri/src/pi_config.rs

@@ -18,8 +18,12 @@ pub(crate) fn build_command(
         request.permission_mode,
     )?;
 
-    let mut command = crate::hidden_command(binary);
+    let target = crate::cli_agent_runtime::command_target_avoiding_windows_cmd_shim(binary)?;
+    let mut command = crate::hidden_command(&target.program);
     crate::cli_agent_runtime::configure_agent_command_environment(&mut command, binary);
+    if let Some(first_arg) = target.first_arg {
+        command.arg(first_arg);
+    }
     command
         .args(build_args())
         .arg(build_prompt(request))
@@ -300,10 +304,15 @@ mod tests {
     }
 
     fn assert_pi_json_mode_args(args: &[String]) {
-        assert_eq!(args[0], "--mode");
-        assert_eq!(args[1], "json");
-        assert!(args.contains(&"--no-session".to_string()));
-        assert!(args.contains(&"--extension".to_string()));
+        assert_eq!(
+            (
+                args.first().map(String::as_str),
+                args.get(1).map(String::as_str),
+                args.iter().any(|arg| arg == "--no-session"),
+                args.iter().any(|arg| arg == "--extension"),
+            ),
+            (Some("--mode"), Some("json"), true, true)
+        );
     }
 
     #[test]
@@ -324,10 +333,20 @@ mod tests {
     }
 
     fn assert_command_identity(command: &std::process::Command, actual_args: &[&OsStr]) {
-        assert_eq!(command.get_program(), OsStr::new("pi"));
-        assert_eq!(actual_args[0], OsStr::new("--mode"));
-        assert_eq!(actual_args[1], OsStr::new("json"));
-        assert_eq!(actual_args.last(), Some(&OsStr::new("Rename the note")));
+        assert_eq!(
+            (
+                command.get_program(),
+                actual_args.first().copied(),
+                actual_args.get(1).copied(),
+                actual_args.last().copied(),
+            ),
+            (
+                OsStr::new("pi"),
+                Some(OsStr::new("--mode")),
+                Some(OsStr::new("json")),
+                Some(OsStr::new("Rename the note")),
+            )
+        );
     }
 
     fn assert_command_vault_scope(
@@ -340,6 +359,50 @@ mod tests {
         assert!(agent_dir.join("mcp.json").exists());
     }
 
+    #[test]
+    fn command_avoids_windows_cmd_shim_for_prompt_args() {
+        let _env_lock = PI_AGENT_ENV_LOCK.lock().unwrap();
+        let source_agent_dir = tempfile::tempdir().unwrap();
+        let agent_dir = tempfile::tempdir().unwrap();
+        let _guard = EnvGuard::set("PI_CODING_AGENT_DIR", source_agent_dir.path());
+        let shim = agent_dir.path().join("pi.cmd");
+        let launcher = agent_dir
+            .path()
+            .join("node_modules")
+            .join("@withpi")
+            .join("pi")
+            .join("bin")
+            .join("pi.exe");
+        std::fs::create_dir_all(launcher.parent().unwrap()).unwrap();
+        std::fs::write(&launcher, "native pi launcher").unwrap();
+        std::fs::write(
+            &shim,
+            r#"@ECHO off
+"%~dp0\node_modules\@withpi\pi\bin\pi.exe" %*
+"#,
+        )
+        .unwrap();
+
+        let command = build_command(&shim, &request(), agent_dir.path()).unwrap();
+        let actual_args = command.get_args().collect::<Vec<_>>();
+
+        assert_eq!(
+            (
+                command.get_program() != shim.as_os_str(),
+                command.get_program(),
+                actual_args.first().copied(),
+                actual_args.last().copied(),
+            ),
+            (
+                true,
+                launcher.as_os_str(),
+                Some(OsStr::new("--mode")),
+                Some(OsStr::new("Rename the note")),
+            ),
+            "Pi npm .cmd shims cannot be spawned directly on Windows"
+        );
+    }
+
     #[test]
     fn command_seeds_temp_agent_dir_from_existing_pi_config() {
         let _env_lock = PI_AGENT_ENV_LOCK.lock().unwrap();
@@ -429,10 +492,20 @@ mod tests {
     }
 
     fn assert_base_mcp_config(json: &serde_json::Value) {
-        assert_eq!(json["settings"]["toolPrefix"], "none");
-        assert_eq!(json["mcpServers"]["tolaria"]["command"], "node");
-        assert_eq!(json["mcpServers"]["tolaria"]["lifecycle"], "lazy");
-        assert_eq!(json["mcpServers"]["tolaria"]["directTools"], true);
+        assert_eq!(
+            (
+                &json["settings"]["toolPrefix"],
+                &json["mcpServers"]["tolaria"]["command"],
+                &json["mcpServers"]["tolaria"]["lifecycle"],
+                &json["mcpServers"]["tolaria"]["directTools"],
+            ),
+            (
+                &serde_json::json!("none"),
+                &serde_json::json!("node"),
+                &serde_json::json!("lazy"),
+                &serde_json::json!(true),
+            )
+        );
     }
 
     fn assert_tolaria_mcp_env(json: &serde_json::Value) {

src-tauri/src/pi_discovery.rs

@@ -88,12 +88,19 @@ fn path_from_successful_output(output: &std::process::Output) -> Option<PathBuf>
 }
 
 fn first_existing_path(stdout: &str) -> Option<PathBuf> {
+    first_existing_path_for_platform(stdout, cfg!(windows))
+}
+
+fn first_existing_path_for_platform(stdout: &str, windows: bool) -> Option<PathBuf> {
     stdout.lines().find_map(|line| {
         let trimmed = line.trim();
         if trimmed.is_empty() {
             return None;
         }
         let candidate = PathBuf::from(trimmed);
+        if windows && !crate::cli_agent_runtime::has_windows_cli_extension(&candidate) {
+            return None;
+        }
         candidate.exists().then_some(candidate)
     })
 }
@@ -358,6 +365,18 @@ mod tests {
         assert_eq!(first_existing_path(&stdout), Some(pi));
     }
 
+    #[test]
+    fn first_existing_windows_path_skips_extensionless_npm_wrapper() {
+        let dir = tempfile::tempdir().unwrap();
+        let wrapper = dir.path().join("pi");
+        let shim = dir.path().join("pi.cmd");
+        std::fs::write(&wrapper, "#!/bin/sh\n").unwrap();
+        std::fs::write(&shim, "@ECHO off\n").unwrap();
+        let stdout = format!("{}\n{}\n", wrapper.display(), shim.display());
+
+        assert_eq!(first_existing_path_for_platform(&stdout, true), Some(shim));
+    }
+
     #[cfg(unix)]
     #[test]
     fn command_path_from_shell_finds_pi_from_interactive_login_shell() {

src/utils/vault-dialog.test.ts

@@ -9,6 +9,7 @@ vi.mock('../lib/appUpdater', () => ({
   RESTART_REQUIRED_FOLDER_PICKER_MESSAGE:
     'Tolaria needs a restart before macOS can open another folder picker. Restart to apply the downloaded update and try again.',
   isRestartRequiredAfterUpdate: vi.fn(() => false),
+  markRestartRequiredAfterUpdate: vi.fn(),
 }))
 
 const openMock = vi.fn()
@@ -21,12 +22,16 @@ import { pickFolder } from './vault-dialog'
 import { isTauri } from '../mock-tauri'
 import {
   isRestartRequiredAfterUpdate,
+  markRestartRequiredAfterUpdate,
   RESTART_REQUIRED_FOLDER_PICKER_MESSAGE,
 } from '../lib/appUpdater'
 
 describe('pickFolder', () => {
   beforeEach(() => {
     vi.restoreAllMocks()
+    vi.clearAllMocks()
+    openMock.mockReset()
+    vi.mocked(isRestartRequiredAfterUpdate).mockReturnValue(false)
   })
 
   it('returns user input from prompt in browser mode', async () => {
@@ -70,6 +75,15 @@ describe('pickFolder', () => {
     await expect(pickFolder('Select vault')).rejects.toThrow(RESTART_REQUIRED_FOLDER_PICKER_MESSAGE)
   })
 
+  it('translates an NSOpenPanel panic into the restart-required folder picker error', async () => {
+    vi.mocked(isTauri).mockReturnValue(true)
+    vi.mocked(isRestartRequiredAfterUpdate).mockReturnValue(false)
+    openMock.mockRejectedValue('panic: unexpected NULL returned from +[NSOpenPanel openPanel]')
+
+    await expect(pickFolder('Select vault')).rejects.toThrow(RESTART_REQUIRED_FOLDER_PICKER_MESSAGE)
+    expect(markRestartRequiredAfterUpdate).toHaveBeenCalledOnce()
+  })
+
   it('normalizes a native single-selection array to its first folder path', async () => {
     vi.mocked(isTauri).mockReturnValue(true)
     vi.mocked(isRestartRequiredAfterUpdate).mockReturnValue(false)
@@ -98,6 +112,7 @@ describe('pickFolder', () => {
     const secondRequest = pickFolder('Open vault folder')
 
     await expect(secondRequest).resolves.toBeNull()
+    await new Promise(resolve => setTimeout(resolve, 0))
     expect(openMock).toHaveBeenCalledTimes(1)
 
     resolveOpen?.('/Users/test/restored-vault')

src/utils/vault-dialog.ts

@@ -7,9 +7,12 @@
 import { isTauri } from '../mock-tauri'
 import {
   isRestartRequiredAfterUpdate,
+  markRestartRequiredAfterUpdate,
   RESTART_REQUIRED_FOLDER_PICKER_MESSAGE,
 } from '../lib/appUpdater'
 
+const NS_OPEN_PANEL_UNAVAILABLE_MARKER = 'unexpected NULL returned from +[NSOpenPanel openPanel]'
+
 export class NativeFolderPickerBlockedError extends Error {
   constructor(message = RESTART_REQUIRED_FOLDER_PICKER_MESSAGE) {
     super(message)
@@ -23,6 +26,16 @@ export function isNativeFolderPickerBlockedError(
   return error instanceof NativeFolderPickerBlockedError
 }
 
+function errorMessage(error: unknown): string {
+  if (typeof error === 'string') return error
+  if (error instanceof Error) return error.message
+  return ''
+}
+
+function isUnavailableNativeFolderPicker(error: unknown): boolean {
+  return errorMessage(error).includes(NS_OPEN_PANEL_UNAVAILABLE_MARKER)
+}
+
 export function formatFolderPickerActionError(
   action: string,
   error: unknown,
@@ -31,12 +44,7 @@ export function formatFolderPickerActionError(
     return error.message
   }
 
-  const message =
-    typeof error === 'string'
-      ? error
-      : error instanceof Error
-        ? error.message
-        : ''
+  const message = errorMessage(error)
 
   return message ? `${action}: ${message}` : action
 }
@@ -77,6 +85,28 @@ function normalizePickedFolderPath(selected: string | string[] | null): string |
 
 let folderPickerRequestInFlight = false
 
+async function pickNativeFolder(title?: string): Promise<string | null> {
+  if (isRestartRequiredAfterUpdate()) {
+    throw new NativeFolderPickerBlockedError()
+  }
+
+  try {
+    const { open } = await import('@tauri-apps/plugin-dialog')
+    const selected = await open({
+      directory: true,
+      multiple: false,
+      title: title ?? 'Select folder',
+    })
+    return normalizePickedFolderPath(selected)
+  } catch (error) {
+    if (isUnavailableNativeFolderPicker(error)) {
+      markRestartRequiredAfterUpdate()
+      throw new NativeFolderPickerBlockedError()
+    }
+    throw error
+  }
+}
+
 /**
  * Opens a native folder picker dialog (Tauri) or falls back to prompt (browser).
  * Returns the selected folder path, or null if the user cancelled.
@@ -87,17 +117,7 @@ export async function pickFolder(title?: string): Promise<string | null> {
   folderPickerRequestInFlight = true
   try {
     if (isTauri()) {
-      if (isRestartRequiredAfterUpdate()) {
-        throw new NativeFolderPickerBlockedError()
-      }
-
-      const { open } = await import('@tauri-apps/plugin-dialog')
-      const selected = await open({
-        directory: true,
-        multiple: false,
-        title: title ?? 'Select folder',
-      })
-      return normalizePickedFolderPath(selected)
+      return await pickNativeFolder(title)
     }
     return normalizePickedFolderPath(prompt(title ?? 'Enter folder path:'))
   } finally {