fix(extensions): validate skill import source paths locally

src/renderer/components/extensions/skills/SkillImportDialog.tsx

@@ -25,7 +25,7 @@ import { FileSearch, FolderOpen, X } from 'lucide-react';
 import { getSuggestedSkillFolderNameFromPath } from './skillFolderNameUtils';
 import { SkillReviewDialog } from './SkillReviewDialog';
 import { resolveSkillProjectPath } from './skillProjectUtils';
-import { validateSkillFolderName } from './skillValidationUtils';
+import { validateSkillFolderName, validateSkillImportSourceDir } from './skillValidationUtils';
 
 import type { SkillReviewPreview } from '@shared/types/extensions';
 
@@ -127,8 +127,16 @@ export const SkillImportDialog = ({
   }
 
   async function handleReview(): Promise<void> {
+    const normalizedSourceDir = sourceDir.trim();
+    const normalizedFolderName = folderName.trim();
+    const sourceDirError = validateSkillImportSourceDir(sourceDir);
+    if (sourceDirError) {
+      setMutationError(sourceDirError);
+      return;
+    }
+
     const folderNameError =
-      folderName.trim().length > 0 ? validateSkillFolderName(folderName) : null;
+      normalizedFolderName.length > 0 ? validateSkillFolderName(normalizedFolderName) : null;
     if (folderNameError) {
       setMutationError(folderNameError);
       return;
@@ -138,8 +146,8 @@ export const SkillImportDialog = ({
     setMutationError(null);
     try {
       const nextPreview = await previewSkillImport({
-        sourceDir,
+        sourceDir: normalizedSourceDir,
-        folderName: folderName || undefined,
+        folderName: normalizedFolderName || undefined,
         scope,
         rootKind,
         projectPath: resolveSkillProjectPath(scope, projectPath),
@@ -158,12 +166,15 @@ export const SkillImportDialog = ({
   }
 
   async function handleConfirmImport(): Promise<void> {
+    const normalizedSourceDir = sourceDir.trim();
+    const normalizedFolderName = folderName.trim();
+
     setImportLoading(true);
     setMutationError(null);
     try {
       const detail = await applySkillImport({
-        sourceDir,
+        sourceDir: normalizedSourceDir,
-        folderName: folderName || undefined,
+        folderName: normalizedFolderName || undefined,
         scope,
         rootKind,
         projectPath: resolveSkillProjectPath(scope, projectPath),
@@ -296,7 +307,7 @@ export const SkillImportDialog = ({
               </p>
               <Button
                 onClick={() => void handleReview()}
-                disabled={!sourceDir || reviewLoading || importLoading}
+                disabled={!sourceDir.trim() || reviewLoading || importLoading}
               >
                 <FileSearch className="mr-1.5 size-3.5" />
                 {reviewLoading ? 'Preparing...' : 'Review And Import'}

src/renderer/components/extensions/skills/skillValidationUtils.ts

@@ -1,6 +1,14 @@
 const MAX_SKILL_FOLDER_NAME_LENGTH = 255;
 const INVALID_SKILL_FOLDER_NAME_CHARS = /[\x00-\x1f/\\:*?"<>|]/u;
 
+export function validateSkillImportSourceDir(value: string): string | null {
+  if (value.trim().length === 0) {
+    return 'Choose a skill folder to import.';
+  }
+
+  return null;
+}
+
 export function validateSkillFolderName(value: string): string | null {
   const trimmed = value.trim();
   if (trimmed.length === 0) {

test/renderer/components/extensions/skills/SkillImportDialog.test.ts

@@ -426,4 +426,49 @@ describe('SkillImportDialog', () => {
       await Promise.resolve();
     });
   });
+
+  it('keeps review disabled for whitespace-only source folders', async () => {
+    const host = document.createElement('div');
+    document.body.appendChild(host);
+    const root = createRoot(host);
+
+    await act(async () => {
+      root.render(
+        React.createElement(SkillImportDialog, {
+          open: true,
+          projectPath: null,
+          projectLabel: null,
+          onClose: vi.fn(),
+          onImported: vi.fn(),
+        })
+      );
+      await Promise.resolve();
+    });
+
+    const sourceInput = host.querySelector('#skill-import-source') as HTMLInputElement;
+    await act(async () => {
+      const setValue = Object.getOwnPropertyDescriptor(HTMLInputElement.prototype, 'value')?.set;
+      setValue?.call(sourceInput, '   ');
+      sourceInput.dispatchEvent(new Event('input', { bubbles: true }));
+      await Promise.resolve();
+    });
+
+    const reviewButton = Array.from(host.querySelectorAll('button')).find((button) =>
+      button.textContent?.includes('Review And Import')
+    ) as HTMLButtonElement;
+
+    expect(reviewButton.disabled).toBe(true);
+
+    await act(async () => {
+      reviewButton.click();
+      await Promise.resolve();
+    });
+
+    expect(storeState.previewSkillImport).not.toHaveBeenCalled();
+
+    await act(async () => {
+      root.unmount();
+      await Promise.resolve();
+    });
+  });
 });

test/renderer/components/extensions/skills/skillValidationUtils.test.ts

@@ -1,8 +1,19 @@
 import { describe, expect, it } from 'vitest';
 
-import { validateSkillFolderName } from '../../../../../src/renderer/components/extensions/skills/skillValidationUtils';
+import {
+  validateSkillFolderName,
+  validateSkillImportSourceDir,
+} from '../../../../../src/renderer/components/extensions/skills/skillValidationUtils';
 
 describe('skillValidationUtils', () => {
+  it('rejects empty import source folders', () => {
+    expect(validateSkillImportSourceDir('   ')).toBe('Choose a skill folder to import.');
+  });
+
+  it('accepts non-empty import source folders', () => {
+    expect(validateSkillImportSourceDir('/tmp/source-skill')).toBeNull();
+  });
+
   it('accepts normal folder names', () => {
     expect(validateSkillFolderName('review-helper')).toBeNull();
   });