diff --git a/apps/desktop/src/renderer/src/App.tsx b/apps/desktop/src/renderer/src/App.tsx
index bf706081..b0b1f698 100644
--- a/apps/desktop/src/renderer/src/App.tsx
+++ b/apps/desktop/src/renderer/src/App.tsx
@@ -1,6 +1,7 @@
 import { useEffect } from 'react'
 import { createHashRouter, Navigate, RouterProvider } from 'react-router-dom'
 import { ThemeProvider } from './components/theme-provider'
+import { TooltipProvider } from '@multica/ui/components/ui/tooltip'
 import Layout from './pages/layout'
 import HomePage from './pages/home'
 import ChatPage from './pages/chat'
@@ -15,8 +16,7 @@ import { useChannelsStore } from './stores/channels'
 
 function OnboardingGuard({ children }: { children: React.ReactNode }) {
   const completed = useOnboardingStore((s) => s.completed)
-  const forceOnboarding = useOnboardingStore((s) => s.forceOnboarding)
-  if (!completed || forceOnboarding) return <Navigate to="/onboarding" replace />
+  if (!completed) return <Navigate to="/onboarding" replace />
   return <>{children}</>
 }
 
@@ -48,7 +48,6 @@ const router = createHashRouter([
 
 export default function App() {
   useEffect(() => {
-    useOnboardingStore.getState().initForceFlag()
     // Prefetch global data at app startup
     useProviderStore.getState().fetch()
     useChannelsStore.getState().fetch()
@@ -56,7 +55,9 @@ export default function App() {
 
   return (
     <ThemeProvider defaultTheme="system" storageKey="multica-theme">
-      <RouterProvider router={router} />
+      <TooltipProvider>
+        <RouterProvider router={router} />
+      </TooltipProvider>
     </ThemeProvider>
   )
 }
diff --git a/apps/desktop/src/renderer/src/pages/layout.tsx b/apps/desktop/src/renderer/src/pages/layout.tsx
index e1d9cb1d..9d0f0c31 100644
--- a/apps/desktop/src/renderer/src/pages/layout.tsx
+++ b/apps/desktop/src/renderer/src/pages/layout.tsx
@@ -1,90 +1,114 @@
 import { Outlet, NavLink, useLocation } from 'react-router-dom'
 import { Toaster } from '@multica/ui/components/ui/sonner'
-import { Button } from '@multica/ui/components/ui/button'
 import { HugeiconsIcon } from '@hugeicons/react'
 import {
-  Settings02Icon,
   Home01Icon,
+  Comment01Icon,
   CodeIcon,
   PlugIcon,
-  Comment01Icon,
   Share08Icon,
   Time04Icon,
 } from '@hugeicons/core-free-icons'
+import {
+  Sidebar,
+  SidebarContent,
+  SidebarGroup,
+  SidebarHeader,
+  SidebarInset,
+  SidebarMenu,
+  SidebarMenuButton,
+  SidebarMenuItem,
+  SidebarProvider,
+  SidebarTrigger,
+  useSidebar,
+} from '@multica/ui/components/ui/sidebar'
 import { cn } from '@multica/ui/lib/utils'
+import { ModeToggle } from '../components/mode-toggle'
 import { DeviceConfirmDialog } from '../components/device-confirm-dialog'
-import ChatPage from './chat'
 
-const tabs = [
-  { path: '/', label: 'Home', icon: Home01Icon, exact: true },
+const navItems = [
+  { path: '/', label: 'Home', icon: Home01Icon },
   { path: '/chat', label: 'Chat', icon: Comment01Icon },
   { path: '/tools', label: 'Tools', icon: CodeIcon },
   { path: '/skills', label: 'Skills', icon: PlugIcon },
   { path: '/channels', label: 'Channels', icon: Share08Icon },
-  { path: '/crons', label: 'Cron', icon: Time04Icon },
+  { path: '/crons', label: 'Crons', icon: Time04Icon },
 ]
 
+function MainHeader() {
+  const { state, isMobile } = useSidebar()
+  const needsTrafficLightSpace = state === 'collapsed' || isMobile
+
+  return (
+    <header className="h-12 shrink-0 flex items-center px-4">
+      {/* Drag placeholder for traffic lights when sidebar is collapsed */}
+      <div
+        className={cn(
+          'h-full shrink-0 transition-[width] duration-200 ease-linear',
+          needsTrafficLightSpace ? 'w-16' : 'w-0'
+        )}
+        style={{ WebkitAppRegion: 'drag' } as React.CSSProperties}
+      />
+
+      <SidebarTrigger />
+
+      {/* Spacer */}
+      <div className="flex-1" />
+
+      {/* Right: Theme toggle */}
+      <ModeToggle />
+    </header>
+  )
+}
+
 export default function Layout() {
   const location = useLocation()
 
   return (
-    <div className="h-dvh flex flex-col bg-background">
-      {/* Header with drag region for macOS */}
-      <header
-        className="flex items-center justify-between px-4 py-3 border-b pl-20"
-        style={{ WebkitAppRegion: 'drag' } as React.CSSProperties}
-      >
-        <div className="flex items-center gap-2">
-          <span className="text-lg font-semibold">Multica</span>
-        </div>
-        <div
-          className="flex items-center gap-1"
-          style={{ WebkitAppRegion: 'no-drag' } as React.CSSProperties}
-        >
-          <Button variant="ghost" size="icon">
-            <HugeiconsIcon icon={Settings02Icon} className="size-5" />
-          </Button>
-        </div>
-      </header>
+    <div className="flex h-screen flex-col bg-background text-foreground">
+      <SidebarProvider className="flex-1 overflow-hidden">
+        <Sidebar>
+        {/* Traffic light area */}
+        <SidebarHeader
+          className="h-12 shrink-0"
+          style={{ WebkitAppRegion: 'drag' } as React.CSSProperties}
+        />
 
-      {/* Tabs */}
-      <nav className="flex gap-1 px-4 py-2 border-b">
-        {tabs.map((tab) => {
-          const isActive = tab.exact
-            ? location.pathname === tab.path
-            : location.pathname.startsWith(tab.path)
+        <SidebarContent>
+          <SidebarGroup>
+            <SidebarMenu>
+              {navItems.map((item) => {
+                const isActive = item.path === '/'
+                  ? location.pathname === '/'
+                  : location.pathname.startsWith(item.path)
+                return (
+                  <SidebarMenuItem key={item.path}>
+                    <NavLink to={item.path}>
+                      <SidebarMenuButton isActive={isActive}>
+                        <HugeiconsIcon icon={item.icon} className="size-4" />
+                        <span>{item.label}</span>
+                      </SidebarMenuButton>
+                    </NavLink>
+                  </SidebarMenuItem>
+                )
+              })}
+            </SidebarMenu>
+          </SidebarGroup>
+        </SidebarContent>
+      </Sidebar>
 
-          return (
-            <NavLink key={tab.path} to={tab.path}>
-              <Button
-                variant={isActive ? 'secondary' : 'ghost'}
-                size="sm"
-                className={cn('gap-2', isActive && 'bg-secondary')}
-              >
-                <HugeiconsIcon icon={tab.icon} className="size-4" />
-                {tab.label}
-              </Button>
-            </NavLink>
-          )
-        })}
-      </nav>
+      <SidebarInset className="overflow-hidden">
+        <MainHeader />
 
-      {/* Content */}
-      <main className="flex-1 overflow-auto relative">
-        {/* ChatPage is always mounted (cached), hidden via CSS */}
-        <div className={cn('absolute inset-0', location.pathname === '/chat' ? '' : 'hidden')}>
-          <ChatPage />
-        </div>
+        {/* Main Content */}
+        <main className="flex-1 overflow-hidden min-h-1">
+          <Outlet />
+        </main>
+      </SidebarInset>
 
-        {/* Other routes render normally via Outlet */}
-        {location.pathname !== '/chat' && (
-          <div className="p-4 h-full">
-            <Outlet />
-          </div>
-        )}
-      </main>
-      <Toaster />
-      <DeviceConfirmDialog />
+        <Toaster />
+        <DeviceConfirmDialog />
+      </SidebarProvider>
     </div>
   )
 }
diff --git a/apps/desktop/src/renderer/src/stores/onboarding.ts b/apps/desktop/src/renderer/src/stores/onboarding.ts
index d627e7fc..3b9cbb17 100644
--- a/apps/desktop/src/renderer/src/stores/onboarding.ts
+++ b/apps/desktop/src/renderer/src/stores/onboarding.ts
@@ -10,7 +10,6 @@ interface AcknowledgementsState {
 
 interface OnboardingStore {
   completed: boolean
-  forceOnboarding: boolean
   currentStep: number
   acknowledgements: AcknowledgementsState
   allAcknowledged: boolean
@@ -23,14 +22,12 @@ interface OnboardingStore {
   setProviderConfigured: (configured: boolean) => void
   setClientConnected: (connected: boolean) => void
   completeOnboarding: () => void
-  initForceFlag: () => Promise<void>
 }
 
 export const useOnboardingStore = create<OnboardingStore>()(
   persist(
     (set, get) => ({
       completed: false,
-      forceOnboarding: false,
       currentStep: 0,
 
       acknowledgements: {
@@ -57,14 +54,7 @@ export const useOnboardingStore = create<OnboardingStore>()(
 
       setClientConnected: (connected) => set({ clientConnected: connected }),
 
-      completeOnboarding: () => set({ completed: true, forceOnboarding: false, currentStep: 0 }),
-
-      initForceFlag: async () => {
-        const flags = await window.electronAPI.app.getFlags()
-        if (flags.forceOnboarding) {
-          set({ forceOnboarding: true })
-        }
-      },
+      completeOnboarding: () => set({ completed: true, currentStep: 0 }),
     }),
     {
       name: 'multica-onboarding',