diff --git a/frontend-modern/src/components/Settings/AISettings.tsx b/frontend-modern/src/components/Settings/AISettings.tsx
index abf05fb90..f87d4b4c5 100644
--- a/frontend-modern/src/components/Settings/AISettings.tsx
+++ b/frontend-modern/src/components/Settings/AISettings.tsx
@@ -12,6 +12,7 @@ import { AIAPI } from '@/api/ai';
 import { AIChatAPI, type ChatSession, type FileChange } from '@/api/aiChat';
 import { hasFeature, loadLicenseStatus } from '@/stores/license';
 import type { AISettings as AISettingsType, AIProvider, AuthMethod } from '@/types/ai';
+import { normalizeChatSessions } from '@/components/Settings/aiSettingsChatSessions';
 
 // Providers are now configured via accordion sections, not a single-provider selector
 
@@ -284,10 +285,10 @@ export const AISettings: Component = () => {
     setChatSessionsLoading(true);
     setChatSessionsError('');
     try {
-      const sessions = await AIChatAPI.listSessions();
+      const sessions = normalizeChatSessions(await AIChatAPI.listSessions());
       setChatSessions(sessions);
       const current = selectedSessionId();
-      if (!Array.isArray(sessions) || sessions.length === 0) {
+      if (sessions.length === 0) {
         setSelectedSessionId('');
       } else if (!current || !sessions.some((session) => session.id === current)) {
         setSelectedSessionId(sessions[0].id);
diff --git a/frontend-modern/src/components/Settings/__tests__/aiSettingsChatSessions.test.ts b/frontend-modern/src/components/Settings/__tests__/aiSettingsChatSessions.test.ts
new file mode 100644
index 000000000..80d03759c
--- /dev/null
+++ b/frontend-modern/src/components/Settings/__tests__/aiSettingsChatSessions.test.ts
@@ -0,0 +1,21 @@
+import { describe, expect, it } from 'vitest';
+
+import { normalizeChatSessions } from '@/components/Settings/aiSettingsChatSessions';
+
+describe('normalizeChatSessions', () => {
+  it('returns the original array when the API payload is valid', () => {
+    const sessions = [
+      { id: 'session-1', title: 'First', message_count: 1, updated_at: '2026-03-25T10:00:00Z' },
+    ];
+
+    expect(normalizeChatSessions(sessions)).toEqual(sessions);
+  });
+
+  it('returns an empty array when the API payload is null', () => {
+    expect(normalizeChatSessions(null)).toEqual([]);
+  });
+
+  it('returns an empty array when the API payload is not an array', () => {
+    expect(normalizeChatSessions({ id: 'session-1' })).toEqual([]);
+  });
+});
diff --git a/frontend-modern/src/components/Settings/aiSettingsChatSessions.ts b/frontend-modern/src/components/Settings/aiSettingsChatSessions.ts
new file mode 100644
index 000000000..58858b5d6
--- /dev/null
+++ b/frontend-modern/src/components/Settings/aiSettingsChatSessions.ts
@@ -0,0 +1,5 @@
+import type { ChatSession } from '@/api/aiChat';
+
+export function normalizeChatSessions(value: unknown): ChatSession[] {
+  return Array.isArray(value) ? value : [];
+}