diff --git a/src/renderer/components/ScriptsView/ScriptsView.tsx b/src/renderer/components/ScriptsView/ScriptsView.tsx
index 6a85fcd..3d58642 100644
--- a/src/renderer/components/ScriptsView/ScriptsView.tsx
+++ b/src/renderer/components/ScriptsView/ScriptsView.tsx
@@ -2,6 +2,7 @@ import React, { useEffect, useState } from 'react';
 import MonacoEditor from '@monaco-editor/react';
 import type { ScriptData } from '../../../main/shared/electronApi';
 import { useAppStore } from '../../store';
+import { BDS_EVENT_SCRIPTS_CHANGED, dispatchWindowEvent } from '../../utils';
 import { getPythonRuntimeManager } from '../../python/runtimeManagerInstance';
 import { useI18n } from '../../i18n';
 import { showToast } from '../Toast';
@@ -197,9 +198,7 @@ export const ScriptsView: React.FC<ScriptsViewProps> = ({ scriptId }) => {
       setScriptContent(updated.content || '');
       const normalizedExisting = toFunctionSlug(updated.slug || updated.title || '');
       setIsSlugManuallyEdited(normalizedExisting !== toFunctionSlug(updated.title || ''));
-      if (typeof window.dispatchEvent === 'function') {
-        window.dispatchEvent(new CustomEvent('bds:scripts-changed'));
-      }
+      dispatchWindowEvent(BDS_EVENT_SCRIPTS_CHANGED);
     } finally {
       setIsSaving(false);
     }
@@ -217,9 +216,7 @@ export const ScriptsView: React.FC<ScriptsViewProps> = ({ scriptId }) => {
         return;
       }
       closeTab(script.id);
-      if (typeof window.dispatchEvent === 'function') {
-        window.dispatchEvent(new CustomEvent('bds:scripts-changed'));
-      }
+      dispatchWindowEvent(BDS_EVENT_SCRIPTS_CHANGED);
     } catch (error) {
       console.error('Failed to delete script:', error);
       showToast.error(t('sidebar.scripts.deleteFailed'));
diff --git a/src/renderer/components/Sidebar/Sidebar.tsx b/src/renderer/components/Sidebar/Sidebar.tsx
index e9336fd..bd54ee5 100644
--- a/src/renderer/components/Sidebar/Sidebar.tsx
+++ b/src/renderer/components/Sidebar/Sidebar.tsx
@@ -1,7 +1,7 @@
 import React, { useState, useEffect, useCallback, useMemo, useRef } from 'react';
 import { useAppStore, PostData, MediaData } from '../../store';
 import { showToast } from '../Toast';
-import { getContrastColor, groupPostsByStatus, loadTagColorMap } from '../../utils';
+import { BDS_EVENT_SCRIPTS_CHANGED, dispatchWindowEvent, getContrastColor, groupPostsByStatus, loadTagColorMap } from '../../utils';
 import type { ChatConversation, ImportDefinitionData } from '../../types/electron';
 import { GitSidebar } from '../GitSidebar/GitSidebar';
 import { scrollToSettingsSection, SettingsCategory } from '../SettingsView/SettingsView';
@@ -1598,7 +1598,7 @@ const ScriptsList: React.FC = () => {
   } = useProjectScopedSidebarData<Array<{ id: string; title: string; updatedAt: string }>[number]>({
     load: loadScripts,
     activeProjectId,
-    refreshEventName: 'bds:scripts-changed',
+    refreshEventName: BDS_EVENT_SCRIPTS_CHANGED,
   });
 
   const handleCreateScript = async () => {
@@ -1619,9 +1619,7 @@ const ScriptsList: React.FC = () => {
         { id: created.id, title: created.title, updatedAt: created.updatedAt },
         ...prev.filter((script) => script.id !== created.id),
       ]);
-      if (typeof window.dispatchEvent === 'function') {
-        window.dispatchEvent(new CustomEvent('bds:scripts-changed'));
-      }
+      dispatchWindowEvent(BDS_EVENT_SCRIPTS_CHANGED);
       openScriptTab(openTab, created.id, 'pin');
       void reloadScripts();
     } catch (error) {
@@ -1640,9 +1638,7 @@ const ScriptsList: React.FC = () => {
       }
       setScripts((prev) => prev.filter((script) => script.id !== scriptId));
       closeTab(scriptId);
-      if (typeof window.dispatchEvent === 'function') {
-        window.dispatchEvent(new CustomEvent('bds:scripts-changed'));
-      }
+      dispatchWindowEvent(BDS_EVENT_SCRIPTS_CHANGED);
     } catch (error) {
       console.error('Failed to delete script:', error);
       showToast.error(t('sidebar.scripts.deleteFailed'));
diff --git a/src/renderer/components/Sidebar/useProjectScopedSidebarData.ts b/src/renderer/components/Sidebar/useProjectScopedSidebarData.ts
index 664a10a..175be09 100644
--- a/src/renderer/components/Sidebar/useProjectScopedSidebarData.ts
+++ b/src/renderer/components/Sidebar/useProjectScopedSidebarData.ts
@@ -1,9 +1,10 @@
 import { useCallback, useEffect, useState, type Dispatch, type SetStateAction } from 'react';
+import { addWindowEventListener, type BdsWindowEventName } from '../../utils';
 
 interface ProjectScopedSidebarDataOptions<TItem> {
   load: () => Promise<TItem[] | null | undefined>;
   activeProjectId?: string;
-  refreshEventName?: string;
+  refreshEventName?: BdsWindowEventName;
 }
 
 interface ProjectScopedSidebarDataResult<TItem> {
@@ -53,18 +54,11 @@ export function useProjectScopedSidebarData<TItem>(options: ProjectScopedSidebar
       return;
     }
 
-    if (typeof window.addEventListener !== 'function' || typeof window.removeEventListener !== 'function') {
-      return;
-    }
-
-    const handleRefreshEvent = () => {
+    const unsubscribe = addWindowEventListener(refreshEventName, () => {
       void reload();
-    };
+    });
 
-    window.addEventListener(refreshEventName, handleRefreshEvent);
-    return () => {
-      window.removeEventListener(refreshEventName, handleRefreshEvent);
-    };
+    return unsubscribe;
   }, [refreshEventName, reload]);
 
   return {
diff --git a/src/renderer/utils/index.ts b/src/renderer/utils/index.ts
index 4c9915f..e68a8a9 100644
--- a/src/renderer/utils/index.ts
+++ b/src/renderer/utils/index.ts
@@ -4,3 +4,4 @@ export { unescapeMacroSyntax } from './markdownEscape';
 export { groupPostsByStatus, type GroupedPosts, type PostStatus } from './postGrouping';
 export { loadTabsForProject, saveTabsForProject } from './tabPersistence';
 export { buildTagColorMap, loadTagColorMap } from './tagColors';
+export { BDS_EVENT_SCRIPTS_CHANGED, addWindowEventListener, dispatchWindowEvent, type BdsWindowEventName } from './windowEvents';
diff --git a/src/renderer/utils/windowEvents.ts b/src/renderer/utils/windowEvents.ts
new file mode 100644
index 0000000..5a9cff3
--- /dev/null
+++ b/src/renderer/utils/windowEvents.ts
@@ -0,0 +1,34 @@
+export const BDS_EVENT_SCRIPTS_CHANGED = 'bds:scripts-changed' as const;
+
+export type BdsWindowEventName =
+  | typeof BDS_EVENT_SCRIPTS_CHANGED
+  | 'bds:site-validation-updated';
+
+export function addWindowEventListener<TDetail = unknown>(
+  eventName: BdsWindowEventName,
+  handler: (event: CustomEvent<TDetail>) => void,
+): () => void {
+  if (typeof window.addEventListener !== 'function' || typeof window.removeEventListener !== 'function') {
+    return () => {};
+  }
+
+  const listener = (event: Event) => {
+    handler(event as CustomEvent<TDetail>);
+  };
+
+  window.addEventListener(eventName, listener as EventListener);
+  return () => {
+    window.removeEventListener(eventName, listener as EventListener);
+  };
+}
+
+export function dispatchWindowEvent<TDetail = unknown>(
+  eventName: BdsWindowEventName,
+  detail?: TDetail,
+): boolean {
+  if (typeof window.dispatchEvent !== 'function') {
+    return false;
+  }
+
+  return window.dispatchEvent(new CustomEvent<TDetail>(eventName, { detail }));
+}
diff --git a/tests/renderer/utils/windowEvents.test.ts b/tests/renderer/utils/windowEvents.test.ts
new file mode 100644
index 0000000..083af63
--- /dev/null
+++ b/tests/renderer/utils/windowEvents.test.ts
@@ -0,0 +1,61 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { addWindowEventListener, dispatchWindowEvent } from '../../../src/renderer/utils/windowEvents';
+
+describe('windowEvents utils', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+
+    const listeners = new Map<string, Set<(event: Event) => void>>();
+    (window as any).addEventListener = vi.fn((type: string, listener: (event: Event) => void) => {
+      if (!listeners.has(type)) {
+        listeners.set(type, new Set());
+      }
+      listeners.get(type)?.add(listener);
+    });
+    (window as any).removeEventListener = vi.fn((type: string, listener: (event: Event) => void) => {
+      listeners.get(type)?.delete(listener);
+    });
+    (window as any).dispatchEvent = vi.fn((event: Event) => {
+      listeners.get(event.type)?.forEach((listener) => listener(event));
+      return true;
+    });
+  });
+
+  it('dispatches custom events with detail payload', () => {
+    const listener = vi.fn();
+    addWindowEventListener('bds:scripts-changed', listener);
+
+    const dispatched = dispatchWindowEvent('bds:scripts-changed', { scriptId: 'script-1' });
+
+    expect(dispatched).toBe(true);
+    expect(listener).toHaveBeenCalledTimes(1);
+    const event = listener.mock.calls[0][0] as CustomEvent<{ scriptId: string }>;
+    expect(event.detail).toEqual({ scriptId: 'script-1' });
+  });
+
+  it('returns no-op unsubscribe when listener APIs are unavailable', () => {
+    const originalAdd = (window as any).addEventListener;
+    const originalRemove = (window as any).removeEventListener;
+    (window as any).addEventListener = undefined;
+    (window as any).removeEventListener = undefined;
+
+    const unsubscribe = addWindowEventListener('bds:scripts-changed', vi.fn());
+    expect(typeof unsubscribe).toBe('function');
+    expect(() => unsubscribe()).not.toThrow();
+
+    (window as any).addEventListener = originalAdd;
+    (window as any).removeEventListener = originalRemove;
+  });
+
+  it('subscribes and unsubscribes listeners', () => {
+    const listener = vi.fn();
+    const unsubscribe = addWindowEventListener('bds:scripts-changed', listener);
+
+    dispatchWindowEvent('bds:scripts-changed');
+    expect(listener).toHaveBeenCalledTimes(1);
+
+    unsubscribe();
+    dispatchWindowEvent('bds:scripts-changed');
+    expect(listener).toHaveBeenCalledTimes(1);
+  });
+});