diff --git a/src-tauri/src/models/project.rs b/src-tauri/src/models/project.rs
index 8413907..1b72c73 100644
--- a/src-tauri/src/models/project.rs
+++ b/src-tauri/src/models/project.rs
@@ -101,6 +101,8 @@ pub struct CodeSettings {
     pub theme: String, // e.g., "github" | "dracula"
     #[serde(default = "default_font_size")]
     pub font_size: u16, // in px
+    #[serde(default = "default_auto_collapse_sidebar")]
+    pub auto_collapse_sidebar: bool,
 }
 
 fn default_code_theme() -> String {
@@ -109,12 +111,16 @@ fn default_code_theme() -> String {
 fn default_font_size() -> u16 {
     14
 }
+fn default_auto_collapse_sidebar() -> bool {
+    false
+}
 
 impl Default for CodeSettings {
     fn default() -> Self {
         Self {
             theme: default_code_theme(),
             font_size: default_font_size(),
+            auto_collapse_sidebar: default_auto_collapse_sidebar(),
         }
     }
 }
diff --git a/src/App.tsx b/src/App.tsx
index f6a99c6..167703f 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,5 +1,5 @@
 import { AppSidebar } from "@/components/app-sidebar"
-import { SidebarProvider, SidebarTrigger, SidebarInset } from "@/components/ui/sidebar"
+import { SidebarProvider, SidebarTrigger, SidebarInset, useSidebar } from "@/components/ui/sidebar"
 import { SidebarWidthProvider } from "@/contexts/sidebar-width-context"
 import { Separator } from "@/components/ui/separator"
 import { 
@@ -80,6 +80,24 @@ function ProjectView({ project, selectedAgent, activeTab, onTabChange }: Project
   )
 }
 
+function SidebarAutoCollapseManager({ activeTab, enabled, projectActive }: { activeTab: string; enabled: boolean; projectActive: boolean }) {
+  const { setOpen } = useSidebar()
+
+  useEffect(() => {
+    setOpen((currentOpen) => {
+      if (!enabled || !projectActive) {
+        return true
+      }
+      if (activeTab === 'code') {
+        return false
+      }
+      return true
+    })
+  }, [activeTab, enabled, projectActive, setOpen])
+
+  return null
+}
+
 function AppContent() {
   const { settings } = useSettings()
   const [isSettingsOpen, setIsSettingsOpen] = useState(false)
@@ -416,6 +434,11 @@ function AppContent() {
   return (
     <SidebarWidthProvider>
       <SidebarProvider>
+        <SidebarAutoCollapseManager
+          activeTab={activeTab}
+          enabled={Boolean(settings.code_settings?.auto_collapse_sidebar)}
+          projectActive={Boolean(currentProject)}
+        />
         <AppSidebar 
           isSettingsOpen={isSettingsOpen} 
           setIsSettingsOpen={setIsSettingsOpen}
diff --git a/src/components/CodeView.tsx b/src/components/CodeView.tsx
index 52f7d18..d4e0475 100644
--- a/src/components/CodeView.tsx
+++ b/src/components/CodeView.tsx
@@ -454,6 +454,10 @@ export function CodeView({ project, tauriInvoke }: CodeViewProps) {
     })();
   }, [project.path]);
 
+  useEffect(() => {
+    setSelectedFile((prev) => (prev ? null : prev));
+  }, [viewScope, workspacePath]);
+
   const handleFileSelect = (file: FileInfo) => {
     setSelectedFile(file);
   };
@@ -464,22 +468,6 @@ export function CodeView({ project, tauriInvoke }: CodeViewProps) {
       {/* File Explorer Sidebar */}
       <div className="w-80 border-r bg-muted/30 flex flex-col min-h-0 h-full">
         <div className="p-2 border-b bg-muted/20 space-y-2">
-          <Label className="text-xs text-muted-foreground">View</Label>
-          {viewScope !== 'workspace' ? (
-            <Select value={viewScope} onValueChange={(v: 'main' | 'workspace') => { setViewScope(v); setSelectedFile(null); }}>
-              <SelectTrigger className="h-8 mt-1">
-                <SelectValue placeholder="Select view" />
-              </SelectTrigger>
-              <SelectContent>
-                <SelectItem value="main">Main Branch</SelectItem>
-                <SelectItem value="workspace" disabled={!workspacePath}>Workspace</SelectItem>
-              </SelectContent>
-            </Select>
-          ) : (
-            <div className="h-8 mt-1 flex items-center text-xs text-muted-foreground">
-              Workspace View
-            </div>
-          )}
           {viewScope !== 'workspace' && (
             <Button size="sm" className="w-full" disabled={creatingWs} onClick={() => setIsCreateOpen(true)}>
               <Plus className="h-4 w-4 mr-2" /> Create Workspace
diff --git a/src/components/SettingsModal.tsx b/src/components/SettingsModal.tsx
index 47e97b7..05f9fec 100644
--- a/src/components/SettingsModal.tsx
+++ b/src/components/SettingsModal.tsx
@@ -99,7 +99,7 @@ export function SettingsModal({ isOpen, onClose, initialTab }: SettingsModalProp
   const [fetchingAgentModels, setFetchingAgentModels] = useState<Record<string, boolean>>({})
   const [agentSettingsLoading, setAgentSettingsLoading] = useState(true)
   const [agentSettingsError, setAgentSettingsError] = useState<string | null>(null)
-  const { updateSettings: updateAppSettings } = useAppSettingsContext()
+  const { updateSettings: updateAppSettings, settings: appSettingsContext } = useAppSettingsContext()
 
   // Code settings
   const [codeTheme, setCodeTheme] = useState<string>('github')
@@ -130,7 +130,7 @@ export function SettingsModal({ isOpen, onClose, initialTab }: SettingsModalProp
         
         // Load app settings with error handling
         try {
-          const appSettings = await invoke<{ show_console_output: boolean, projects_folder: string, file_mentions_enabled: boolean, ui_theme?: string, code_settings?: { theme: string, font_size: number }, chat_send_shortcut?: 'enter' | 'mod+enter', show_welcome_recent_projects?: boolean, max_chat_history?: number, default_cli_agent?: string }>('load_app_settings')
+          const appSettings = await invoke<{ show_console_output: boolean, projects_folder: string, file_mentions_enabled: boolean, ui_theme?: string, code_settings?: { theme: string, font_size: number, auto_collapse_sidebar?: boolean }, chat_send_shortcut?: 'enter' | 'mod+enter', show_welcome_recent_projects?: boolean, max_chat_history?: number, default_cli_agent?: string }>('load_app_settings')
           console.log('✅ App settings loaded:', appSettings)
           if (appSettings) {
             setShowConsoleOutput(appSettings.show_console_output)
@@ -156,7 +156,7 @@ export function SettingsModal({ isOpen, onClose, initialTab }: SettingsModalProp
               setDefaultProjectsFolder(appSettings.projects_folder)
               setTempDefaultProjectsFolder(appSettings.projects_folder)
             }
-            const code = appSettings.code_settings || { theme: 'github', font_size: 14 }
+            const code = appSettings.code_settings || { theme: 'github', font_size: 14, auto_collapse_sidebar: false }
             setCodeTheme(code.theme)
             setTempCodeTheme(code.theme)
             setCodeFontSize(code.font_size)
@@ -362,7 +362,7 @@ export function SettingsModal({ isOpen, onClose, initialTab }: SettingsModalProp
             chat_send_shortcut: tempChatSendShortcut,
             show_welcome_recent_projects: tempShowWelcomeRecentProjects,
             default_cli_agent: tempDefaultCliAgent,
-            code_settings: { theme: codeTheme, font_size: codeFontSize }
+            code_settings: { theme: codeTheme, font_size: codeFontSize, auto_collapse_sidebar: appSettingsContext.code_settings.auto_collapse_sidebar }
           }
         await updateAppSettings(appSettings)
         // Also update native window theme
@@ -388,7 +388,7 @@ export function SettingsModal({ isOpen, onClose, initialTab }: SettingsModalProp
           chat_send_shortcut: tempChatSendShortcut,
           show_welcome_recent_projects: tempShowWelcomeRecentProjects,
           default_cli_agent: tempDefaultCliAgent,
-          code_settings: { theme: codeTheme, font_size: codeFontSize },
+          code_settings: { theme: codeTheme, font_size: codeFontSize, auto_collapse_sidebar: appSettingsContext.code_settings.auto_collapse_sidebar },
         }
         await updateAppSettings(appSettings)
         setChatSendShortcut(tempChatSendShortcut)
@@ -411,7 +411,7 @@ export function SettingsModal({ isOpen, onClose, initialTab }: SettingsModalProp
           chat_send_shortcut: tempChatSendShortcut,
           show_welcome_recent_projects: tempShowWelcomeRecentProjects,
           default_cli_agent: tempDefaultCliAgent,
-          code_settings: { theme: codeTheme, font_size: codeFontSize },
+          code_settings: { theme: codeTheme, font_size: codeFontSize, auto_collapse_sidebar: appSettingsContext.code_settings.auto_collapse_sidebar },
         }
         await updateAppSettings(appSettings)
         setMaxChatHistory(tempMaxChatHistory)
@@ -435,7 +435,7 @@ export function SettingsModal({ isOpen, onClose, initialTab }: SettingsModalProp
           chat_send_shortcut: tempChatSendShortcut,
           show_welcome_recent_projects: tempShowWelcomeRecentProjects,
           default_cli_agent: tempDefaultCliAgent,
-          code_settings: { theme: codeTheme, font_size: codeFontSize },
+          code_settings: { theme: codeTheme, font_size: codeFontSize, auto_collapse_sidebar: appSettingsContext.code_settings.auto_collapse_sidebar },
         }
         await updateAppSettings(appSettings)
         setShowWelcomeRecentProjects(tempShowWelcomeRecentProjects)
@@ -609,7 +609,7 @@ export function SettingsModal({ isOpen, onClose, initialTab }: SettingsModalProp
         chat_send_shortcut: tempChatSendShortcut,
         show_welcome_recent_projects: tempShowWelcomeRecentProjects,
         default_cli_agent: tempDefaultCliAgent,
-        code_settings: { theme: tempCodeTheme, font_size: tempCodeFontSize }
+        code_settings: { theme: tempCodeTheme, font_size: tempCodeFontSize, auto_collapse_sidebar: appSettingsContext.code_settings.auto_collapse_sidebar }
       }
       await updateAppSettings(appSettings)
       
diff --git a/src/components/__tests__/App.projectSelection.chatDefault.test.tsx b/src/components/__tests__/App.projectSelection.chatDefault.test.tsx
index 07a71c4..99407b1 100644
--- a/src/components/__tests__/App.projectSelection.chatDefault.test.tsx
+++ b/src/components/__tests__/App.projectSelection.chatDefault.test.tsx
@@ -76,7 +76,7 @@ const defaultSettings = {
   file_mentions_enabled: true,
   show_welcome_recent_projects: true,
   chat_send_shortcut: 'mod+enter',
-  code_settings: { theme: 'github', font_size: 14 },
+  code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false },
   ui_theme: 'auto',
 }
 
diff --git a/src/components/__tests__/App.sidebar.autoCollapse.test.tsx b/src/components/__tests__/App.sidebar.autoCollapse.test.tsx
new file mode 100644
index 0000000..9fe8f97
--- /dev/null
+++ b/src/components/__tests__/App.sidebar.autoCollapse.test.tsx
@@ -0,0 +1,167 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, waitFor, fireEvent } from '@testing-library/react'
+import App from '@/App'
+
+const project = {
+  name: 'Sample Project',
+  path: '/projects/sample',
+  last_accessed: Math.floor(Date.now() / 1000),
+  is_git_repo: true,
+  git_branch: 'main',
+  git_status: 'clean',
+}
+
+const tauriCore = vi.hoisted(() => ({
+  invoke: vi.fn(),
+}))
+
+vi.mock('@tauri-apps/api/core', () => tauriCore)
+vi.mock('@tauri-apps/api/event', () => ({ listen: vi.fn(async () => () => {}) }))
+vi.mock('@/components/ChatInterface', () => ({ ChatInterface: () => <div data-testid="chat-interface" /> }))
+vi.mock('@/components/CodeView', () => ({ CodeView: () => <div data-testid="code-view" /> }))
+vi.mock('@/components/HistoryView', () => ({ HistoryView: () => <div data-testid="history-view" /> }))
+vi.mock('@/components/AIAgentStatusBar', () => ({ AIAgentStatusBar: () => <div data-testid="status-bar" /> }))
+vi.mock('@/components/ui/tabs', () => {
+  const React = require('react')
+  const TabsContext = React.createContext<{ value: string; onValueChange?: (value: string) => void } | null>(null)
+
+  const Tabs = ({ value, onValueChange, children }: any) => (
+    <TabsContext.Provider value={{ value, onValueChange }}>
+      <div data-testid="tabs" data-active-tab={value}>{children}</div>
+    </TabsContext.Provider>
+  )
+
+  const TabsList = ({ children, ...props }: any) => (
+    <div role="tablist" {...props}>{children}</div>
+  )
+
+  const TabsTrigger = ({ value, children, ...props }: any) => {
+    const context = React.useContext(TabsContext)
+    if (!context) {
+      throw new Error('TabsTrigger must be used within Tabs')
+    }
+    const isActive = context.value === value
+    return (
+      <button
+        type="button"
+        role="tab"
+        data-state={isActive ? 'active' : 'inactive'}
+        onClick={() => context.onValueChange?.(value)}
+        {...props}
+      >
+        {children}
+      </button>
+    )
+  }
+
+  const TabsContent = ({ value, children, forceMount, ...props }: any) => {
+    const context = React.useContext(TabsContext)
+    if (!context) {
+      throw new Error('TabsContent must be used within Tabs')
+    }
+    if (!forceMount && context.value !== value) return null
+    return (
+      <div data-state={context.value === value ? 'active' : 'inactive'} {...props}>
+        {children}
+      </div>
+    )
+  }
+
+  return { Tabs, TabsList, TabsTrigger, TabsContent }
+})
+
+let autoCollapse = true
+
+const buildSettings = () => ({
+  show_console_output: true,
+  projects_folder: '',
+  file_mentions_enabled: true,
+  show_welcome_recent_projects: true,
+  chat_send_shortcut: 'mod+enter' as const,
+  ui_theme: 'auto',
+  default_cli_agent: 'claude' as const,
+  code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: autoCollapse },
+})
+
+if (typeof window !== 'undefined' && !window.matchMedia) {
+  Object.defineProperty(window, 'matchMedia', {
+    writable: true,
+    value: vi.fn().mockImplementation(() => ({
+      matches: false,
+      addEventListener: vi.fn(),
+      removeEventListener: vi.fn(),
+    })),
+  })
+}
+
+if (typeof document !== 'undefined') describe('App sidebar auto-collapse in code view', () => {
+  beforeEach(() => {
+    const invoke = tauriCore.invoke as unknown as ReturnType<typeof vi.fn>
+    invoke.mockReset()
+    autoCollapse = true
+    invoke.mockImplementation(async (cmd: string) => {
+      switch (cmd) {
+        case 'load_app_settings':
+          return buildSettings()
+        case 'list_recent_projects':
+          return [project]
+        case 'refresh_recent_projects':
+          return [project]
+        case 'open_existing_project':
+          return project
+        case 'get_cli_project_path':
+          return null
+        case 'clear_cli_project_path':
+          return null
+        case 'get_user_home_directory':
+          return '/projects'
+        case 'set_window_theme':
+        case 'add_project_to_recent':
+        case 'save_app_settings':
+          return null
+        default:
+          return null
+      }
+    })
+  })
+
+  it('collapses the sidebar when entering the Code tab and restores it afterwards', async () => {
+    render(<App />)
+
+    const projectButton = await screen.findByRole('button', { name: /Sample Project/i })
+    fireEvent.click(projectButton)
+
+    const sidebarPanel = await screen.findByTestId('app-sidebar')
+    const sidebar = sidebarPanel.closest('[data-state]') as HTMLElement | null
+    expect(sidebar).not.toBeNull()
+    await waitFor(() => expect(sidebar).toHaveAttribute('data-state', 'expanded'))
+
+    const codeTab = screen.getByRole('tab', { name: /Code/i })
+    fireEvent.click(codeTab)
+
+    await waitFor(() => expect(sidebar).toHaveAttribute('data-state', 'collapsed'))
+
+    const chatTab = screen.getByRole('tab', { name: /Chat/i })
+    fireEvent.click(chatTab)
+
+    await waitFor(() => expect(sidebar).toHaveAttribute('data-state', 'expanded'))
+  })
+
+  it('keeps sidebar expanded when preference is disabled', async () => {
+    autoCollapse = false
+    render(<App />)
+
+    const projectButton = await screen.findByRole('button', { name: /Sample Project/i })
+    fireEvent.click(projectButton)
+
+    const sidebarPanel = await screen.findByTestId('app-sidebar')
+    const sidebar = sidebarPanel.closest('[data-state]') as HTMLElement | null
+    expect(sidebar).not.toBeNull()
+    await waitFor(() => expect(sidebar).toHaveAttribute('data-state', 'expanded'))
+
+    const codeTab = screen.getByRole('tab', { name: /Code/i })
+    fireEvent.click(codeTab)
+
+    await waitFor(() => expect(sidebar).toHaveAttribute('data-state', 'expanded'))
+  })
+})
diff --git a/src/components/__tests__/App.welcome.recents.test.tsx b/src/components/__tests__/App.welcome.recents.test.tsx
index 59bfb43..72f0566 100644
--- a/src/components/__tests__/App.welcome.recents.test.tsx
+++ b/src/components/__tests__/App.welcome.recents.test.tsx
@@ -19,7 +19,7 @@ const { RECENT_PROJECTS, defaultInvokeImplementation } = vi.hoisted(() => {
   const handler = async (cmd: string) => {
     switch (cmd) {
       case 'load_app_settings':
-        return { show_welcome_recent_projects: true, show_console_output: true, file_mentions_enabled: true, projects_folder: '', ui_theme: 'auto', chat_send_shortcut: 'mod+enter', code_settings: { theme: 'github', font_size: 14 } }
+        return { show_welcome_recent_projects: true, show_console_output: true, file_mentions_enabled: true, projects_folder: '', ui_theme: 'auto', chat_send_shortcut: 'mod+enter', code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false } }
       case 'list_recent_projects':
         return recents
       case 'refresh_recent_projects':
@@ -167,7 +167,7 @@ if (typeof document !== 'undefined') describe('App welcome screen recent project
     ;(invoke as any).mockImplementation(async (cmd: string) => {
       switch (cmd) {
         case 'load_app_settings':
-          return { show_welcome_recent_projects: false, show_console_output: true, file_mentions_enabled: true, projects_folder: '', ui_theme: 'auto', chat_send_shortcut: 'mod+enter', code_settings: { theme: 'github', font_size: 14 } }
+          return { show_welcome_recent_projects: false, show_console_output: true, file_mentions_enabled: true, projects_folder: '', ui_theme: 'auto', chat_send_shortcut: 'mod+enter', code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false } }
         case 'list_recent_projects':
           return []
         case 'check_ai_agents':
diff --git a/src/components/__tests__/CodeView.refresh.test.tsx b/src/components/__tests__/CodeView.refresh.test.tsx
index 09690c6..dd3606b 100644
--- a/src/components/__tests__/CodeView.refresh.test.tsx
+++ b/src/components/__tests__/CodeView.refresh.test.tsx
@@ -23,7 +23,7 @@ vi.mock('@tauri-apps/api/core', () => ({
         file_mentions_enabled: true,
         chat_send_shortcut: 'mod+enter',
         show_welcome_recent_projects: true,
-        code_settings: { theme: 'github', font_size: 14 },
+        code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false },
         ui_theme: 'auto',
       }
     }
diff --git a/src/components/__tests__/codeview.workspaces.test.tsx b/src/components/__tests__/codeview.workspaces.test.tsx
index 39a9ab2..ac5c5e7 100644
--- a/src/components/__tests__/codeview.workspaces.test.tsx
+++ b/src/components/__tests__/codeview.workspaces.test.tsx
@@ -23,6 +23,8 @@ if (typeof document !== 'undefined') describe('CodeView workspaces', () => {
         <CodeView project={project as any} tauriInvoke={fakeInvoke as any} />
       </SettingsProvider>
     )
+    expect(screen.queryByText('View')).not.toBeInTheDocument()
+    expect(screen.queryByText(/workspace view/i)).not.toBeInTheDocument()
     // Switch to workspace view automatically (since mocked list is non-empty)
     await waitFor(() => expect(screen.getByText('Workspace')).toBeInTheDocument())
     // Open workspace select
diff --git a/src/components/app-sidebar.tsx b/src/components/app-sidebar.tsx
index 9d21ac1..75c7bcb 100644
--- a/src/components/app-sidebar.tsx
+++ b/src/components/app-sidebar.tsx
@@ -68,7 +68,7 @@ export function AppSidebar({ isSettingsOpen, setIsSettingsOpen, onRefreshProject
 
   return (
     <ResizableSidebar>
-      <Sidebar variant="sidebar" className="flex flex-col" {...props}>
+      <Sidebar variant="sidebar" className="flex flex-col" data-testid="app-sidebar" {...props}>
         {/* Sidebar title bar drag area - matching the main content */}
         <div 
           className="h-7 w-full drag-area" 
diff --git a/src/components/chat/__tests__/ChatInterface.defaultAgent.test.tsx b/src/components/chat/__tests__/ChatInterface.defaultAgent.test.tsx
index 69da73c..753134b 100644
--- a/src/components/chat/__tests__/ChatInterface.defaultAgent.test.tsx
+++ b/src/components/chat/__tests__/ChatInterface.defaultAgent.test.tsx
@@ -61,7 +61,7 @@ vi.mock('@/contexts/settings-context', () => ({
       chat_send_shortcut: 'mod+enter',
       show_welcome_recent_projects: true,
       max_chat_history: 15,
-      code_settings: { theme: 'github', font_size: 14 },
+      code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false },
       default_cli_agent: currentDefaultAgent,
     },
     updateSettings: vi.fn(),
diff --git a/src/components/chat/__tests__/ChatInterface.historyLimit.test.tsx b/src/components/chat/__tests__/ChatInterface.historyLimit.test.tsx
index ccb3ff7..137b594 100644
--- a/src/components/chat/__tests__/ChatInterface.historyLimit.test.tsx
+++ b/src/components/chat/__tests__/ChatInterface.historyLimit.test.tsx
@@ -55,7 +55,7 @@ const defaultInvokeImpl = async (cmd: string) => {
         projects_folder: '',
         ui_theme: 'auto',
         show_welcome_recent_projects: true,
-        code_settings: { theme: 'github', font_size: 14 },
+        code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false },
       }
     default:
       return null
diff --git a/src/components/settings/CodeSettings.tsx b/src/components/settings/CodeSettings.tsx
index 79b5372..6433c3d 100644
--- a/src/components/settings/CodeSettings.tsx
+++ b/src/components/settings/CodeSettings.tsx
@@ -4,21 +4,25 @@ import { Input } from "@/components/ui/input";
 import { Button } from "@/components/ui/button";
 import { useSettings } from "@/contexts/settings-context";
 import { useState, useEffect } from "react";
+import { Switch } from "@/components/ui/switch";
 
 export function CodeSettings() {
   const { settings, updateSettings } = useSettings();
   const [tempTheme, setTempTheme] = useState(settings.code_settings.theme);
   const [tempFontSize, setTempFontSize] = useState(settings.code_settings.font_size);
+  const [tempAutoCollapse, setTempAutoCollapse] = useState(settings.code_settings.auto_collapse_sidebar);
   const [isSaving, setIsSaving] = useState(false);
 
   // Sync temp values when settings change from external sources
   useEffect(() => {
     setTempTheme(settings.code_settings.theme);
     setTempFontSize(settings.code_settings.font_size);
-  }, [settings.code_settings.theme, settings.code_settings.font_size]);
+    setTempAutoCollapse(settings.code_settings.auto_collapse_sidebar);
+  }, [settings.code_settings.theme, settings.code_settings.font_size, settings.code_settings.auto_collapse_sidebar]);
   
   const hasChanges = tempTheme !== settings.code_settings.theme || 
-                    tempFontSize !== settings.code_settings.font_size;
+                    tempFontSize !== settings.code_settings.font_size ||
+                    tempAutoCollapse !== settings.code_settings.auto_collapse_sidebar;
 
   const handleSave = async () => {
     if (!hasChanges) return;
@@ -28,7 +32,8 @@ export function CodeSettings() {
       await updateSettings({
         code_settings: {
           theme: tempTheme,
-          font_size: tempFontSize
+          font_size: tempFontSize,
+          auto_collapse_sidebar: tempAutoCollapse,
         }
       });
     } catch (error) {
@@ -41,6 +46,7 @@ export function CodeSettings() {
   const handleDiscard = () => {
     setTempTheme(settings.code_settings.theme);
     setTempFontSize(settings.code_settings.font_size);
+    setTempAutoCollapse(settings.code_settings.auto_collapse_sidebar);
   };
   return (
     <div className="space-y-6">
@@ -77,6 +83,23 @@ export function CodeSettings() {
         </div>
       </div>
 
+      <div className="space-y-2">
+        <div className="flex items-center justify-between gap-4 rounded-md border border-border/60 p-4">
+          <div>
+            <Label htmlFor="auto-collapse-sidebar">Auto-collapse app sidebar</Label>
+            <p className="text-xs text-muted-foreground mt-1">
+              Hide the project sidebar whenever the Code tab is active. It reappears in Chat and History views.
+            </p>
+          </div>
+          <Switch
+            id="auto-collapse-sidebar"
+            checked={tempAutoCollapse}
+            onCheckedChange={setTempAutoCollapse}
+            aria-label="Auto-collapse app sidebar"
+          />
+        </div>
+      </div>
+
       {hasChanges && (
         <div className="flex gap-2 pt-4 border-t">
           <Button onClick={handleSave} disabled={isSaving}>
diff --git a/src/components/settings/__tests__/ChatSettings.shortcut.save.test.tsx b/src/components/settings/__tests__/ChatSettings.shortcut.save.test.tsx
index c7ba3a6..59a69f6 100644
--- a/src/components/settings/__tests__/ChatSettings.shortcut.save.test.tsx
+++ b/src/components/settings/__tests__/ChatSettings.shortcut.save.test.tsx
@@ -11,7 +11,7 @@ vi.mock('@tauri-apps/api/core', () => {
       invokes.push({ cmd, args })
       switch (cmd) {
         case 'load_app_settings':
-          return { show_console_output: true, projects_folder: '', file_mentions_enabled: true, ui_theme: 'auto', code_settings: { theme: 'github', font_size: 14 }, chat_send_shortcut: 'mod+enter' }
+          return { show_console_output: true, projects_folder: '', file_mentions_enabled: true, ui_theme: 'auto', code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false }, chat_send_shortcut: 'mod+enter' }
         case 'get_default_projects_folder':
           return '/tmp'
         case 'load_agent_settings':
diff --git a/src/components/settings/__tests__/CodeSettings.autoCollapse.test.tsx b/src/components/settings/__tests__/CodeSettings.autoCollapse.test.tsx
new file mode 100644
index 0000000..2a5bd38
--- /dev/null
+++ b/src/components/settings/__tests__/CodeSettings.autoCollapse.test.tsx
@@ -0,0 +1,56 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, fireEvent, waitFor } from '@testing-library/react'
+import { CodeSettings } from '@/components/settings/CodeSettings'
+
+const updateSettings = vi.fn()
+const baseSettings = {
+  show_console_output: true,
+  projects_folder: '',
+  file_mentions_enabled: true,
+  ui_theme: 'auto',
+  chat_send_shortcut: 'mod+enter' as const,
+  show_welcome_recent_projects: true,
+  max_chat_history: 15,
+  default_cli_agent: 'claude' as const,
+  code_settings: {
+    theme: 'github',
+    font_size: 14,
+    auto_collapse_sidebar: false,
+  },
+}
+
+vi.mock('@/contexts/settings-context', () => ({
+  useSettings: () => ({
+    settings: JSON.parse(JSON.stringify(baseSettings)),
+    updateSettings,
+  }),
+}))
+
+if (typeof document !== 'undefined') describe('CodeSettings auto-collapse preference', () => {
+  beforeEach(() => {
+    updateSettings.mockReset()
+  })
+
+  it('saves updated auto-collapse flag when toggled', async () => {
+    render(<CodeSettings />)
+
+    const toggle = screen.getByRole('switch', { name: /auto-collapse app sidebar/i })
+    expect(toggle).toHaveAttribute('data-state', 'unchecked')
+
+    fireEvent.click(toggle)
+    await waitFor(() => expect(toggle).toHaveAttribute('data-state', 'checked'))
+
+    const saveButton = screen.getByRole('button', { name: /save changes/i })
+    fireEvent.click(saveButton)
+
+    await waitFor(() => {
+      expect(updateSettings).toHaveBeenCalledWith({
+        code_settings: {
+          theme: 'github',
+          font_size: 14,
+          auto_collapse_sidebar: true,
+        },
+      })
+    })
+  })
+})
diff --git a/src/components/settings/__tests__/SettingsModal.defaultAgent.test.tsx b/src/components/settings/__tests__/SettingsModal.defaultAgent.test.tsx
index 1402bfb..daa7cf4 100644
--- a/src/components/settings/__tests__/SettingsModal.defaultAgent.test.tsx
+++ b/src/components/settings/__tests__/SettingsModal.defaultAgent.test.tsx
@@ -19,7 +19,7 @@ vi.mock('@tauri-apps/api/core', () => {
             chat_send_shortcut: 'mod+enter',
             show_welcome_recent_projects: true,
             max_chat_history: 15,
-            code_settings: { theme: 'github', font_size: 14 },
+            code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false },
             default_cli_agent: 'gemini',
           }
         case 'get_default_projects_folder':
diff --git a/src/components/settings/__tests__/SettingsModal.welcomeToggle.autosave.test.tsx b/src/components/settings/__tests__/SettingsModal.welcomeToggle.autosave.test.tsx
index 95336f5..5b124a0 100644
--- a/src/components/settings/__tests__/SettingsModal.welcomeToggle.autosave.test.tsx
+++ b/src/components/settings/__tests__/SettingsModal.welcomeToggle.autosave.test.tsx
@@ -8,7 +8,7 @@ import { SettingsProvider } from '@/contexts/settings-context'
 const invokeMock = vi.fn(async (cmd: string, args?: any) => {
   switch (cmd) {
     case 'load_app_settings':
-      return { show_console_output: true, projects_folder: '', file_mentions_enabled: true, ui_theme: 'auto', chat_send_shortcut: 'mod+enter', show_welcome_recent_projects: true, code_settings: { theme: 'github', font_size: 14 } }
+      return { show_console_output: true, projects_folder: '', file_mentions_enabled: true, ui_theme: 'auto', chat_send_shortcut: 'mod+enter', show_welcome_recent_projects: true, code_settings: { theme: 'github', font_size: 14, auto_collapse_sidebar: false } }
     case 'set_window_theme':
       return null
     case 'save_app_settings':
@@ -56,4 +56,3 @@ if (typeof document !== 'undefined') describe('SettingsModal autosaves welcome r
     expect(lastArgs.settings.show_welcome_recent_projects).toBe(false)
   })
 })
-
diff --git a/src/contexts/settings-context.tsx b/src/contexts/settings-context.tsx
index 92b44e7..724e1e2 100644
--- a/src/contexts/settings-context.tsx
+++ b/src/contexts/settings-context.tsx
@@ -15,6 +15,7 @@ function normalizeDefaultAgent(value?: string | null): DefaultCliAgent {
 interface CodeSettings {
   theme: string;
   font_size: number;
+  auto_collapse_sidebar: boolean;
 }
 
 interface AppSettings {
@@ -45,7 +46,8 @@ const defaultSettings: AppSettings = {
   max_chat_history: 15,
   code_settings: {
     theme: 'github',
-    font_size: 14
+    font_size: 14,
+    auto_collapse_sidebar: false,
   },
   default_cli_agent: FALLBACK_AGENT,
 };
@@ -59,12 +61,17 @@ export function SettingsProvider({ children }: { children: ReactNode }) {
   const refreshSettings = async () => {
     try {
       setIsLoading(true);
-      const appSettings = await invoke<AppSettings>('load_app_settings');
+      const appSettings = await invoke<Partial<AppSettings>>('load_app_settings');
       console.log('🔄 Settings refreshed:', appSettings);
-      const defaultCliAgent = normalizeDefaultAgent(appSettings.default_cli_agent);
+      const defaultCliAgent = normalizeDefaultAgent(appSettings?.default_cli_agent);
+      const mergedCodeSettings = {
+        ...defaultSettings.code_settings,
+        ...(appSettings.code_settings || {}),
+      };
       setSettings({
         ...defaultSettings,
         ...appSettings,
+        code_settings: mergedCodeSettings,
         default_cli_agent: defaultCliAgent,
       });
     } catch (error) {
@@ -77,9 +84,17 @@ export function SettingsProvider({ children }: { children: ReactNode }) {
 
   const updateSettings = async (newSettings: Partial<AppSettings>) => {
     try {
-      const updatedSettings = {
+      const mergedCodeSettings = newSettings.code_settings
+        ? {
+            ...settings.code_settings,
+            ...newSettings.code_settings,
+          }
+        : settings.code_settings;
+
+      const updatedSettings: AppSettings = {
         ...settings,
         ...newSettings,
+        code_settings: mergedCodeSettings,
       };
       updatedSettings.default_cli_agent = normalizeDefaultAgent(updatedSettings.default_cli_agent);
       await invoke('save_app_settings', { settings: updatedSettings });
diff --git a/src/types/settings.ts b/src/types/settings.ts
index bd25ab1..bbacea6 100644
--- a/src/types/settings.ts
+++ b/src/types/settings.ts
@@ -29,7 +29,7 @@ export interface AppSettings {
   show_welcome_recent_projects?: boolean;
   // Maximum number of chat messages retained per session
   max_chat_history?: number;
-  code_settings?: { theme: string; font_size: number };
+  code_settings?: { theme: string; font_size: number; auto_collapse_sidebar?: boolean };
 }
 
 // ============================