diff --git a/src/App.tsx b/src/App.tsx
index 73cf7e7f..c11602c1 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,55 +1,153 @@
-import { RouterProvider, createBrowserRouter } from 'react-router-dom';
 import { I18nextProvider } from 'react-i18next';
-import { ThemeProvider } from './contexts/ThemeContext';
+import {
+  Navigate,
+  Outlet,
+  RouterProvider,
+  createBrowserRouter,
+  useParams,
+} from 'react-router-dom';
 import { AuthProvider, ProtectedRoute } from './components/auth';
+import { ThemeProvider } from './contexts/ThemeContext';
+import { PluginsProvider } from './contexts/PluginsContext';
+import { TaskMasterProvider } from './contexts/TaskMasterContext';
+import { TasksSettingsProvider } from './contexts/TasksSettingsContext';
+import { WebSocketProvider } from './contexts/WebSocketContext';
 import i18n from './i18n/config.js';
-import { RootLayout } from '@/components/refactored/shared/RootLayout';
+import { SystemUIProvider } from '@/components/refactored/shared/contexts/system-ui-context/SystemUIProvider';
+import { RootLayout } from '@/components/refactored/shared/layout/RootLayout';
 
-// Mock page components
-const Home = () => <div className="p-8"><h1>Home Page</h1><p>Select a session or create a new project.</p></div>;
-const WorkspaceContent = () => <div className="p-8"><h1>Workspace View</h1><p>Select a session or start a new one.</p></div>;
-const SessionContent = () => <div className="p-8"><h1>Session View</h1><p>Chat interface goes here.</p></div>;
+const isValidRouteTab = (value: string | undefined): boolean => {
+  if (!value) {
+    return false;
+  }
 
-const router = createBrowserRouter([
-  {
-    path: "/",
-    element: <RootLayout />, // The layout wraps all children
-    children: [
-      { 
-        path: "/",
-        element: <Home />,
-      },
-      {
-        path: "/session/:sessionId",
-        element: <SessionContent />,
-      },
-      {
-        path: "/sessions/:sessionId",
-        element: <SessionContent />,
-      },
-      {
-        path: "/workspace/:workspaceId",
-        element: <WorkspaceContent />,
-      },
-    ],
-  },
-]);
+  const normalizedValue = decodeURIComponent(value);
+  return (
+    normalizedValue === 'chat' ||
+    normalizedValue === 'shell' ||
+    normalizedValue === 'files' ||
+    normalizedValue === 'git' ||
+    normalizedValue === 'tasks' ||
+    normalizedValue === 'preview' ||
+    normalizedValue.startsWith('plugin:')
+  );
+};
+
+function NoWorkspaceRoute() {
+  return (
+    <div className="flex h-full items-center justify-center p-8">
+      <div className="max-w-md space-y-2 text-center">
+        <h1 className="text-2xl font-semibold">Choose Your Project</h1>
+        <p className="text-sm text-muted-foreground">
+          This is the root route (`/`) empty state. Select a workspace from the sidebar to continue.
+        </p>
+      </div>
+    </div>
+  );
+}
+
+function WorkspaceLayout() {
+  const { workspaceId } = useParams<{ workspaceId: string }>();
+  if (!workspaceId) {
+    return <Navigate to="/" replace />;
+  }
+
+  return (
+    <div className="min-h-0 flex-1 overflow-auto">
+      <Outlet />
+    </div>
+  );
+}
+
+function WorkspaceTabRoute() {
+  const { workspaceId, sessionId, tab } = useParams<{
+    workspaceId: string;
+    sessionId?: string;
+    tab: string;
+  }>();
+
+  if (!workspaceId) {
+    return <Navigate to="/" replace />;
+  }
+
+  if (!isValidRouteTab(tab)) {
+    return <Navigate to="../chat" replace />;
+  }
+
+  const decodedWorkspaceId = decodeURIComponent(workspaceId);
+  const decodedSessionId = sessionId ? decodeURIComponent(sessionId) : null;
+  const decodedTab = tab ? decodeURIComponent(tab) : 'chat';
+
+  return (
+    <div className="h-full p-6">
+      <div className="rounded-xl border border-border/70 bg-card/30 p-5">
+        <h2 className="text-lg font-semibold">{decodedTab} view</h2>
+        <p className="mt-2 text-sm text-muted-foreground">
+          Workspace: <span className="font-medium text-foreground">{decodedWorkspaceId}</span>
+        </p>
+        <p className="mt-1 text-sm text-muted-foreground">
+          Session:{' '}
+          <span className="font-medium text-foreground">
+            {decodedSessionId || 'none (workspace-level tab)'}
+          </span>
+        </p>
+      </div>
+    </div>
+  );
+}
+
+const router = createBrowserRouter(
+  [
+    {
+      path: '/',
+      element: <RootLayout />,
+      children: [
+        { index: true, element: <NoWorkspaceRoute /> },
+        {
+          path: 'workspaces/:workspaceId',
+          element: <WorkspaceLayout />,
+          children: [
+            { index: true, element: <Navigate to="chat" replace /> },
+            { path: ':tab', element: <WorkspaceTabRoute /> },
+            {
+              path: 'sessions/:sessionId',
+              children: [
+                { index: true, element: <Navigate to="chat" replace /> },
+                { path: ':tab', element: <WorkspaceTabRoute /> },
+              ],
+            },
+          ],
+        },
+      ],
+    },
+  ],
+  { basename: window.__ROUTER_BASENAME__ || '' },
+);
 
 export default function App() {
   return (
     <I18nextProvider i18n={i18n}>
       <ThemeProvider>
         <AuthProvider>
-          <ProtectedRoute>
-              <RouterProvider router={router} />
-          </ProtectedRoute>
+          <WebSocketProvider>
+            <PluginsProvider>
+              <TasksSettingsProvider>
+                <TaskMasterProvider>
+                  <SystemUIProvider>
+                    <ProtectedRoute>
+                      <RouterProvider router={router} />
+                    </ProtectedRoute>
+                  </SystemUIProvider>
+                </TaskMasterProvider>
+              </TasksSettingsProvider>
+            </PluginsProvider>
+          </WebSocketProvider>
         </AuthProvider>
       </ThemeProvider>
     </I18nextProvider>
   );
 }
 
-
 // import { BrowserRouter as Router, Route, Routes } from 'react-router-dom';
 // import { I18nextProvider } from 'react-i18next';
 // import { ThemeProvider } from './contexts/ThemeContext';
diff --git a/src/components/refactored/shared/contexts/system-ui-context/SystemUIContext.ts b/src/components/refactored/shared/contexts/system-ui-context/SystemUIContext.ts
new file mode 100644
index 00000000..63c68c29
--- /dev/null
+++ b/src/components/refactored/shared/contexts/system-ui-context/SystemUIContext.ts
@@ -0,0 +1,9 @@
+import { createContext } from 'react';
+import type { Dispatch, SetStateAction } from 'react';
+
+export type SystemUIContextValue = {
+  sidebarIsCollapsed: boolean;
+  setSidebarIsCollapsed: Dispatch<SetStateAction<boolean>>;
+};
+
+export const SystemUIContext = createContext<SystemUIContextValue | null>(null);
diff --git a/src/components/refactored/shared/contexts/system-ui-context/SystemUIProvider.tsx b/src/components/refactored/shared/contexts/system-ui-context/SystemUIProvider.tsx
new file mode 100644
index 00000000..e479f303
--- /dev/null
+++ b/src/components/refactored/shared/contexts/system-ui-context/SystemUIProvider.tsx
@@ -0,0 +1,20 @@
+import { useMemo, useState, type ReactNode } from 'react';
+import { SystemUIContext, type SystemUIContextValue } from '@/components/refactored/shared/contexts/system-ui-context/SystemUIContext';
+
+export function SystemUIProvider({ children }: { children: ReactNode }) {
+  const [sidebarIsCollapsed, setSidebarIsCollapsed] = useState(false);
+
+  const value = useMemo<SystemUIContextValue>(
+    () => ({
+      sidebarIsCollapsed,
+      setSidebarIsCollapsed,
+    }),
+    [sidebarIsCollapsed],
+  );
+
+  return (
+    <SystemUIContext.Provider value={value}>
+      {children}
+    </SystemUIContext.Provider>
+  );
+}
diff --git a/src/components/refactored/shared/contexts/system-ui-context/useSystemUI.ts b/src/components/refactored/shared/contexts/system-ui-context/useSystemUI.ts
new file mode 100644
index 00000000..d37d82ae
--- /dev/null
+++ b/src/components/refactored/shared/contexts/system-ui-context/useSystemUI.ts
@@ -0,0 +1,11 @@
+import { useContext } from 'react';
+import { SystemUIContext } from '@/components/refactored/shared/contexts/system-ui-context/SystemUIContext';
+
+export const useSystemUI = () => {
+  const context = useContext(SystemUIContext);
+  if (!context) {
+    throw new Error('useSystemUI must be used within SystemUIProvider');
+  }
+
+  return context;
+};
diff --git a/src/components/refactored/shared/layout/MainHeading.tsx b/src/components/refactored/shared/layout/MainHeading.tsx
new file mode 100644
index 00000000..87b520bb
--- /dev/null
+++ b/src/components/refactored/shared/layout/MainHeading.tsx
@@ -0,0 +1,187 @@
+import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
+import { useNavigate, useParams } from 'react-router-dom';
+import { useTranslation } from 'react-i18next';
+import type { AppTab } from '@/types/app';
+import { usePlugins } from '@/contexts/PluginsContext';
+import { useDeviceSettings } from '@/hooks/useDeviceSettings';
+import { useSystemUI } from '@/components/refactored/shared/contexts/system-ui-context/useSystemUI';
+import { MainHeadingTabSwitcher } from '@/components/refactored/shared/layout/MainHeadingTabSwitcher';
+
+type MainHeadingRouteParams = {
+  workspaceId?: string;
+  sessionId?: string;
+  tab?: string;
+};
+
+const decodeValue = (value?: string): string => {
+  if (!value) {
+    return '';
+  }
+
+  try {
+    return decodeURIComponent(value);
+  } catch {
+    return value;
+  }
+};
+
+const getTabTitle = (tab: AppTab, pluginDisplayName: string | undefined, t: (key: string) => string) => {
+  if (tab.startsWith('plugin:') && pluginDisplayName) {
+    return pluginDisplayName;
+  }
+
+  if (tab === 'files') {
+    return t('mainContent.projectFiles');
+  }
+
+  if (tab === 'git') {
+    return t('tabs.git');
+  }
+
+  if (tab === 'tasks') {
+    return 'TaskMaster';
+  }
+
+  if (tab === 'shell') {
+    return t('tabs.shell');
+  }
+
+  return t('tabs.chat');
+};
+
+export function MainHeading() {
+  const navigate = useNavigate();
+  const { t } = useTranslation(['common', 'sidebar']);
+  const { plugins } = usePlugins();
+  const { isMobile } = useDeviceSettings({ trackPWA: false });
+  const { sidebarIsCollapsed, setSidebarIsCollapsed } = useSystemUI();
+  const { workspaceId, sessionId, tab } = useParams<MainHeadingRouteParams>();
+
+  const scrollRef = useRef<HTMLDivElement>(null);
+  const [canScrollLeft, setCanScrollLeft] = useState(false);
+  const [canScrollRight, setCanScrollRight] = useState(false);
+
+  const decodedWorkspaceId = useMemo(() => decodeValue(workspaceId), [workspaceId]);
+  const decodedSessionId = useMemo(() => decodeValue(sessionId), [sessionId]);
+  const activeTab = useMemo<AppTab>(() => {
+    const routeTab = decodeValue(tab);
+    return (routeTab || 'chat') as AppTab;
+  }, [tab]);
+
+  const pluginDisplayName = useMemo(
+    () =>
+      activeTab.startsWith('plugin:')
+        ? plugins.find((plugin) => plugin.name === activeTab.replace('plugin:', ''))?.displayName
+        : undefined,
+    [activeTab, plugins],
+  );
+
+  const title = useMemo(() => {
+    if (activeTab === 'chat' && decodedSessionId) {
+      return decodedSessionId;
+    }
+
+    if (activeTab === 'chat') {
+      return t('mainContent.newSession');
+    }
+
+    return getTabTitle(activeTab, pluginDisplayName, t);
+  }, [activeTab, decodedSessionId, pluginDisplayName, t]);
+
+  const updateScrollState = useCallback(() => {
+    const element = scrollRef.current;
+    if (!element) {
+      return;
+    }
+
+    setCanScrollLeft(element.scrollLeft > 2);
+    setCanScrollRight(element.scrollLeft < element.scrollWidth - element.clientWidth - 2);
+  }, []);
+
+  useEffect(() => {
+    const element = scrollRef.current;
+    if (!element || isMobile) {
+      return;
+    }
+
+    updateScrollState();
+    const observer = new ResizeObserver(updateScrollState);
+    observer.observe(element);
+
+    return () => observer.disconnect();
+  }, [isMobile, updateScrollState]);
+
+  if (!workspaceId) {
+    return null;
+  }
+
+  const handleTabSelect = (nextTab: AppTab) => {
+    // Preserve workspace/session context while switching only the active tab path segment.
+    const encodedWorkspaceId = encodeURIComponent(decodedWorkspaceId);
+    const encodedTab = encodeURIComponent(nextTab);
+
+    if (decodedSessionId) {
+      navigate(
+        `/workspaces/${encodedWorkspaceId}/sessions/${encodeURIComponent(decodedSessionId)}/${encodedTab}`,
+      );
+      return;
+    }
+
+    navigate(`/workspaces/${encodedWorkspaceId}/${encodedTab}`);
+  };
+
+  return (
+    <div className="pwa-header-safe flex-shrink-0 border-b border-border/60 bg-background px-3 py-1.5 sm:px-4 sm:py-2">
+      <div className="flex items-center justify-between gap-3">
+        <div className="flex min-w-0 flex-1 items-center gap-2">
+          {isMobile && (
+            <button
+              onClick={() => setSidebarIsCollapsed((previousValue) => !previousValue)}
+              className="pwa-menu-button flex-shrink-0 touch-manipulation rounded-lg p-1.5 text-muted-foreground transition-colors hover:bg-accent/60 hover:text-foreground active:scale-95"
+              aria-label={sidebarIsCollapsed ? t('common:versionUpdate.ariaLabels.showSidebar') : t('sidebar:tooltips.hideSidebar')}
+              title={sidebarIsCollapsed ? t('common:versionUpdate.ariaLabels.showSidebar') : t('sidebar:tooltips.hideSidebar')}
+            >
+              <svg className="h-5 w-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path
+                  strokeLinecap="round"
+                  strokeLinejoin="round"
+                  strokeWidth={2}
+                  d="M4 6h16M4 12h16M4 18h16"
+                />
+              </svg>
+            </button>
+          )}
+
+          <div className="scrollbar-hide flex min-w-0 flex-1 items-center gap-2 overflow-x-auto">
+            <div className="min-w-0 flex-1">
+              <h2 className="scrollbar-hide overflow-x-auto whitespace-nowrap text-sm font-semibold leading-tight text-foreground">
+                {title}
+              </h2>
+              <div className="truncate text-[11px] leading-tight text-muted-foreground">
+                {decodedWorkspaceId}
+              </div>
+            </div>
+          </div>
+        </div>
+
+        {!isMobile && (
+          <div className="relative min-w-0 flex-shrink overflow-hidden sm:flex-shrink-0">
+            {canScrollLeft && (
+              <div className="pointer-events-none absolute inset-y-0 left-0 z-10 w-6 bg-gradient-to-r from-background to-transparent" />
+            )}
+            <div
+              ref={scrollRef}
+              onScroll={updateScrollState}
+              className="scrollbar-hide overflow-x-auto"
+            >
+              <MainHeadingTabSwitcher activeTab={activeTab} onTabSelect={handleTabSelect} />
+            </div>
+            {canScrollRight && (
+              <div className="pointer-events-none absolute inset-y-0 right-0 z-10 w-6 bg-gradient-to-l from-background to-transparent" />
+            )}
+          </div>
+        )}
+      </div>
+    </div>
+  );
+}
diff --git a/src/components/refactored/shared/layout/MainHeadingTabSwitcher.tsx b/src/components/refactored/shared/layout/MainHeadingTabSwitcher.tsx
new file mode 100644
index 00000000..0ddd2bc0
--- /dev/null
+++ b/src/components/refactored/shared/layout/MainHeadingTabSwitcher.tsx
@@ -0,0 +1,98 @@
+import { ClipboardCheck, Folder, GitBranch, MessageSquare, Terminal, type LucideIcon } from 'lucide-react';
+import { useTranslation } from 'react-i18next';
+import { usePlugins } from '@/contexts/PluginsContext';
+import { useTasksSettings } from '@/contexts/TasksSettingsContext';
+import { Pill, PillBar, Tooltip } from '@/shared/view/ui';
+import type { AppTab } from '@/types/app';
+import PluginIcon from '@/components/plugins/view/PluginIcon';
+
+type TasksSettingsContextValue = {
+  tasksEnabled: boolean;
+  isTaskMasterInstalled: boolean | null;
+};
+
+type BuiltInTab = {
+  kind: 'builtin';
+  id: AppTab;
+  labelKey: string;
+  icon: LucideIcon;
+};
+
+type PluginTab = {
+  kind: 'plugin';
+  id: AppTab;
+  label: string;
+  pluginName: string;
+  iconFile: string;
+};
+
+type TabDefinition = BuiltInTab | PluginTab;
+
+type MainHeadingTabSwitcherProps = {
+  activeTab: AppTab;
+  onTabSelect: (tabId: AppTab) => void;
+};
+
+const BASE_TABS: BuiltInTab[] = [
+  { kind: 'builtin', id: 'chat', labelKey: 'tabs.chat', icon: MessageSquare },
+  { kind: 'builtin', id: 'shell', labelKey: 'tabs.shell', icon: Terminal },
+  { kind: 'builtin', id: 'files', labelKey: 'tabs.files', icon: Folder },
+  { kind: 'builtin', id: 'git', labelKey: 'tabs.git', icon: GitBranch },
+];
+
+const TASKS_TAB: BuiltInTab = {
+  kind: 'builtin',
+  id: 'tasks',
+  labelKey: 'tabs.tasks',
+  icon: ClipboardCheck,
+};
+
+export function MainHeadingTabSwitcher({ activeTab, onTabSelect }: MainHeadingTabSwitcherProps) {
+  const { t } = useTranslation('common');
+  const { plugins } = usePlugins();
+  const { tasksEnabled, isTaskMasterInstalled } = useTasksSettings() as TasksSettingsContextValue;
+  const shouldShowTasksTab = Boolean(tasksEnabled && isTaskMasterInstalled);
+
+  const builtInTabs: BuiltInTab[] = shouldShowTasksTab ? [...BASE_TABS, TASKS_TAB] : BASE_TABS;
+  const pluginTabs: PluginTab[] = plugins
+    .filter((plugin) => plugin.enabled)
+    .map((plugin) => ({
+      kind: 'plugin',
+      id: `plugin:${plugin.name}` as AppTab,
+      label: plugin.displayName,
+      pluginName: plugin.name,
+      iconFile: plugin.icon,
+    }));
+
+  const tabs: TabDefinition[] = [...builtInTabs, ...pluginTabs];
+
+  return (
+    <PillBar>
+      {tabs.map((tab) => {
+        const isActive = tab.id === activeTab;
+        const displayLabel = tab.kind === 'builtin' ? t(tab.labelKey) : tab.label;
+
+        return (
+          <Tooltip key={tab.id} content={displayLabel} position="bottom">
+            <Pill
+              isActive={isActive}
+              onClick={() => onTabSelect(tab.id)}
+              className="px-2.5 py-[5px]"
+            >
+              {tab.kind === 'builtin' ? (
+                <tab.icon className="h-3.5 w-3.5" strokeWidth={isActive ? 2.2 : 1.8} />
+              ) : (
+                <PluginIcon
+                  pluginName={tab.pluginName}
+                  iconFile={tab.iconFile}
+                  className="flex h-3.5 w-3.5 items-center justify-center [&>svg]:h-full [&>svg]:w-full"
+                />
+              )}
+              <span className="hidden lg:inline">{displayLabel}</span>
+            </Pill>
+          </Tooltip>
+        );
+      })}
+    </PillBar>
+  );
+}
diff --git a/src/components/refactored/shared/layout/RootLayout.tsx b/src/components/refactored/shared/layout/RootLayout.tsx
index 374178d5..2e516b7e 100644
--- a/src/components/refactored/shared/layout/RootLayout.tsx
+++ b/src/components/refactored/shared/layout/RootLayout.tsx
@@ -1,15 +1,17 @@
-
 import { Outlet } from 'react-router-dom';
 import { Sidebar } from '@/components/refactored/sidebar/view/Sidebar';
-
+import { MainHeading } from '@/components/refactored/shared/layout/MainHeading';
 
 export function RootLayout() {
   return (
     <div className="flex h-screen w-full overflow-hidden bg-background">
       <Sidebar />
-      <main className="relative flex-1 overflow-hidden">
-        <Outlet />
-      </main>
+      <div className="flex min-w-0 flex-1 flex-col">
+        <MainHeading />
+        <main className="relative min-h-0 flex-1 overflow-hidden">
+          <Outlet />
+        </main>
+      </div>
     </div>
   );
 }
diff --git a/src/components/refactored/sidebar/hooks/useSidebarSettings.ts b/src/components/refactored/sidebar/hooks/useSidebarSettings.ts
deleted file mode 100644
index 5e5d1fe0..00000000
--- a/src/components/refactored/sidebar/hooks/useSidebarSettings.ts
+++ /dev/null
@@ -1,18 +0,0 @@
-import { useState } from 'react';
-
-/**
- * Hook layer (The Manager)
- * Manages the layout states for the sidebar, such as collapse/open.
- */
-export const useSidebarSettings = () => {
-  const [isCollapsed, setIsCollapsed] = useState(false);
-
-  const toggleCollapse = () => setIsCollapsed((prev) => !prev);
-  const setCollapsed = (value: boolean) => setIsCollapsed(value);
-
-  return {
-    isCollapsed,
-    toggleCollapse,
-    setCollapsed,
-  };
-};
diff --git a/src/components/refactored/sidebar/view/Sidebar.tsx b/src/components/refactored/sidebar/view/Sidebar.tsx
index 171089e9..b003443f 100644
--- a/src/components/refactored/sidebar/view/Sidebar.tsx
+++ b/src/components/refactored/sidebar/view/Sidebar.tsx
@@ -1,18 +1,23 @@
 import SidebarFooter from './SidebarFooter';
-import { useSidebarSettings } from '@/components/refactored/sidebar/hooks/useSidebarSettings';
 import { useSidebarModals } from '@/components/refactored/sidebar/hooks/useSidebarModals';
 import { useWorkspaces } from '@/components/refactored/sidebar/hooks/useWorkspaces';
 import SidebarHeader from '@/components/refactored/sidebar/view/SidebarHeader';
 import { SidebarDeleteModals } from '@/components/refactored/sidebar/view/SidebarDeleteModals';
 import { SidebarWorkspaceList } from '@/components/refactored/sidebar/view/SidebarWorkspaceList';
 import { SidebarCollapsed } from '@/components/refactored/sidebar/view/SidebarCollapsed';
+import { useSystemUI } from '@/components/refactored/shared/contexts/system-ui-context/useSystemUI';
+import { useDeviceSettings } from '@/hooks/useDeviceSettings';
 import { cn } from '@/lib/utils';
 import ProjectCreationWizard from '@/components/project-creation-wizard';
 import VersionUpgradeModal from '@/components/version-upgrade/view';
 import Settings from '@/components/settings/view/Settings';
 
 export function Sidebar() {
-  const { isCollapsed, toggleCollapse, setCollapsed } = useSidebarSettings();
+  const { isMobile } = useDeviceSettings({ trackPWA: false });
+  const { sidebarIsCollapsed, setSidebarIsCollapsed } = useSystemUI();
+  const isCollapsed = sidebarIsCollapsed;
+  const toggleCollapse = () => setSidebarIsCollapsed((previousValue) => !previousValue);
+  const setCollapsed = (value: boolean) => setSidebarIsCollapsed(value);
   const {
     workspaces,
     starredWorkspaces,
@@ -148,7 +153,8 @@ export function Sidebar() {
           )}
         </aside>
 
-        {isCollapsed && (
+        {/* Keep collapsed rail desktop-only; mobile uses the header hamburger to reopen. */}
+        {isCollapsed && !isMobile && (
           <aside className="fixed inset-y-0 left-0 z-40 h-full border-r border-border md:relative">
             <SidebarCollapsed
               onExpand={() => setCollapsed(false)}