diff --git a/src/web-server/routes/index.ts b/src/web-server/routes/index.ts
index 4dc44164..8761df91 100644
--- a/src/web-server/routes/index.ts
+++ b/src/web-server/routes/index.ts
@@ -22,6 +22,7 @@ import copilotRoutes from './copilot-routes';
 import miscRoutes from './misc-routes';
 import cliproxyServerRoutes from './proxy-routes';
 import authRoutes from './auth-routes';
+import persistRoutes from './persist-routes';
 
 // Create the main API router
 export const apiRoutes = Router();
@@ -42,6 +43,9 @@ apiRoutes.use('/health', healthRoutes);
 // ==================== Dashboard Auth ====================
 apiRoutes.use('/auth', authRoutes);
 
+// ==================== Persist (Backup Management) ====================
+apiRoutes.use('/persist', persistRoutes);
+
 // ==================== CLIProxy ====================
 // Variants, auth, accounts, stats, status, models, error logs
 apiRoutes.use('/cliproxy', variantRoutes);
diff --git a/src/web-server/routes/persist-routes.ts b/src/web-server/routes/persist-routes.ts
new file mode 100644
index 00000000..80f1b915
--- /dev/null
+++ b/src/web-server/routes/persist-routes.ts
@@ -0,0 +1,148 @@
+/**
+ * Persist Routes - Backup management for ~/.claude/settings.json
+ */
+
+import { Router, Request, Response } from 'express';
+import * as fs from 'fs';
+import * as path from 'path';
+import * as os from 'os';
+
+const router = Router();
+
+interface BackupFile {
+  path: string;
+  timestamp: string;
+  date: Date;
+}
+
+/** Get Claude settings.json path */
+function getClaudeSettingsPath(): string {
+  return path.join(os.homedir(), '.claude', 'settings.json');
+}
+
+/** Check if path is a symlink (security check) */
+function isSymlink(filePath: string): boolean {
+  try {
+    const stats = fs.lstatSync(filePath);
+    return stats.isSymbolicLink();
+  } catch {
+    return false;
+  }
+}
+
+/** Get all backup files sorted by date (newest first) */
+function getBackupFiles(): BackupFile[] {
+  const settingsPath = getClaudeSettingsPath();
+  const dir = path.dirname(settingsPath);
+  if (!fs.existsSync(dir)) {
+    return [];
+  }
+  const backupPattern = /^settings\.json\.backup\.(\d{8}_\d{6})$/;
+  const files = fs
+    .readdirSync(dir)
+    .filter((f) => backupPattern.test(f))
+    .map((f) => {
+      const match = f.match(backupPattern);
+      if (!match) return null;
+      const timestamp = match[1];
+      const year = parseInt(timestamp.slice(0, 4));
+      const month = parseInt(timestamp.slice(4, 6)) - 1;
+      const day = parseInt(timestamp.slice(6, 8));
+      const hour = parseInt(timestamp.slice(9, 11));
+      const min = parseInt(timestamp.slice(11, 13));
+      const sec = parseInt(timestamp.slice(13, 15));
+      return {
+        path: path.join(dir, f),
+        timestamp,
+        date: new Date(year, month, day, hour, min, sec),
+      };
+    })
+    .filter((f): f is BackupFile => f !== null)
+    .sort((a, b) => b.date.getTime() - a.date.getTime());
+  return files;
+}
+
+/**
+ * GET /api/persist/backups - List available backups
+ */
+router.get('/backups', (_req: Request, res: Response): void => {
+  try {
+    const backups = getBackupFiles();
+    res.json({
+      backups: backups.map((b, i) => ({
+        timestamp: b.timestamp,
+        date: b.date.toISOString(),
+        isLatest: i === 0,
+      })),
+    });
+  } catch (error) {
+    res.status(500).json({ error: (error as Error).message });
+  }
+});
+
+/**
+ * POST /api/persist/restore - Restore from a backup
+ * Body: { timestamp?: string } - If not provided, restores latest
+ */
+router.post('/restore', (req: Request, res: Response): void => {
+  try {
+    const { timestamp } = req.body;
+    const backups = getBackupFiles();
+
+    if (backups.length === 0) {
+      res.status(404).json({ error: 'No backups found' });
+      return;
+    }
+
+    // Find backup
+    let backup: BackupFile;
+    if (!timestamp) {
+      backup = backups[0]; // Latest
+    } else {
+      const found = backups.find((b) => b.timestamp === timestamp);
+      if (!found) {
+        res.status(404).json({ error: `Backup not found: ${timestamp}` });
+        return;
+      }
+      backup = found;
+    }
+
+    // Validate backup JSON
+    try {
+      const content = fs.readFileSync(backup.path, 'utf8');
+      const parsed = JSON.parse(content);
+      if (typeof parsed !== 'object' || parsed === null || Array.isArray(parsed)) {
+        res.status(400).json({ error: 'Backup file is corrupted' });
+        return;
+      }
+    } catch {
+      res.status(400).json({ error: 'Backup file is corrupted or invalid JSON' });
+      return;
+    }
+
+    // Security checks
+    if (isSymlink(backup.path)) {
+      res.status(400).json({ error: 'Backup file is a symlink - refusing for security' });
+      return;
+    }
+
+    const settingsPath = getClaudeSettingsPath();
+    if (isSymlink(settingsPath)) {
+      res.status(400).json({ error: 'settings.json is a symlink - refusing for security' });
+      return;
+    }
+
+    // Restore
+    fs.copyFileSync(backup.path, settingsPath);
+
+    res.json({
+      success: true,
+      timestamp: backup.timestamp,
+      date: backup.date.toISOString(),
+    });
+  } catch (error) {
+    res.status(500).json({ error: (error as Error).message });
+  }
+});
+
+export default router;
diff --git a/ui/src/components/cliproxy/provider-editor/account-item.tsx b/ui/src/components/cliproxy/provider-editor/account-item.tsx
index 8c6ac2f0..dd4a1989 100644
--- a/ui/src/components/cliproxy/provider-editor/account-item.tsx
+++ b/ui/src/components/cliproxy/provider-editor/account-item.tsx
@@ -24,6 +24,7 @@ import {
   HelpCircle,
   Pause,
   Play,
+  AlertCircle,
 } from 'lucide-react';
 import {
   cn,
@@ -95,13 +96,13 @@ export function AccountItem({
   showQuota,
 }: AccountItemProps) {
   // Fetch runtime stats to get actual lastUsedAt (more accurate than file state)
-  const { data: stats } = useCliproxyStats(showQuota && account.provider === 'agy');
+  const { data: stats } = useCliproxyStats(showQuota);
 
-  // Fetch quota for 'agy' provider accounts
+  // Fetch quota for all provider accounts
   const { data: quota, isLoading: quotaLoading } = useAccountQuota(
     account.provider,
     account.id,
-    showQuota && account.provider === 'agy'
+    showQuota
   );
 
   // Get last used time from runtime stats (more accurate than file)
@@ -217,8 +218,8 @@ export function AccountItem({
         </DropdownMenu>
       </div>
 
-      {/* Quota bar - only for 'agy' provider */}
-      {showQuota && account.provider === 'agy' && (
+      {/* Quota bar - supports all providers with quota API */}
+      {showQuota && (
         <div className="pl-11">
           {quotaLoading ? (
             <div className="flex items-center gap-2 text-xs text-muted-foreground">
@@ -285,8 +286,25 @@ export function AccountItem({
                 </Tooltip>
               </TooltipProvider>
             </div>
-          ) : quota?.error ? (
-            <div className="text-xs text-muted-foreground">{quota.error}</div>
+          ) : quota?.error || (quota && !quota.success) ? (
+            <TooltipProvider>
+              <Tooltip>
+                <TooltipTrigger asChild>
+                  <div className="flex items-center gap-1.5">
+                    <Badge
+                      variant="outline"
+                      className="text-[10px] h-5 px-2 gap-1 border-muted-foreground/50 text-muted-foreground"
+                    >
+                      <AlertCircle className="w-3 h-3" />
+                      N/A
+                    </Badge>
+                  </div>
+                </TooltipTrigger>
+                <TooltipContent side="bottom">
+                  <p className="text-xs">{quota?.error || 'Quota information unavailable'}</p>
+                </TooltipContent>
+              </Tooltip>
+            </TooltipProvider>
           ) : null}
         </div>
       )}
diff --git a/ui/src/hooks/use-cliproxy-stats.ts b/ui/src/hooks/use-cliproxy-stats.ts
index cc9cf222..0bc54a0c 100644
--- a/ui/src/hooks/use-cliproxy-stats.ts
+++ b/ui/src/hooks/use-cliproxy-stats.ts
@@ -218,13 +218,13 @@ async function fetchAccountQuota(provider: string, accountId: string): Promise<Q
 
 /**
  * Hook to get account quota
- * Only enabled for 'agy' provider (Antigravity) as it's the only one supporting quota
+ * Supports all providers that have quota API implemented
  */
 export function useAccountQuota(provider: string, accountId: string, enabled = true) {
   return useQuery({
     queryKey: ['account-quota', provider, accountId],
     queryFn: () => fetchAccountQuota(provider, accountId),
-    enabled: enabled && provider === 'agy' && !!accountId,
+    enabled: enabled && !!accountId,
     staleTime: 30000, // Consider stale after 30s (tokens can refresh anytime)
     refetchInterval: 60000, // Refresh every 1 minute
     retry: 1,
diff --git a/ui/src/pages/settings/components/tab-navigation.tsx b/ui/src/pages/settings/components/tab-navigation.tsx
index a318d81d..5f0eabba 100644
--- a/ui/src/pages/settings/components/tab-navigation.tsx
+++ b/ui/src/pages/settings/components/tab-navigation.tsx
@@ -4,7 +4,7 @@
  */
 
 import { Tabs, TabsList, TabsTrigger } from '@/components/ui/tabs';
-import { Globe, Settings2, Server, KeyRound } from 'lucide-react';
+import { Globe, Settings2, Server, KeyRound, Archive } from 'lucide-react';
 import type { SettingsTab } from '../types';
 
 interface TabNavigationProps {
@@ -32,6 +32,10 @@ export function TabNavigation({ activeTab, onTabChange }: TabNavigationProps) {
           <KeyRound className="w-4 h-4" />
           Auth
         </TabsTrigger>
+        <TabsTrigger value="backups" className="flex-1 gap-2">
+          <Archive className="w-4 h-4" />
+          Backups
+        </TabsTrigger>
       </TabsList>
     </Tabs>
   );
diff --git a/ui/src/pages/settings/index.tsx b/ui/src/pages/settings/index.tsx
index ce86a63c..e395db9c 100644
--- a/ui/src/pages/settings/index.tsx
+++ b/ui/src/pages/settings/index.tsx
@@ -19,6 +19,7 @@ const WebSearchSection = lazy(() => import('./sections/websearch'));
 const GlobalEnvSection = lazy(() => import('./sections/globalenv-section'));
 const ProxySection = lazy(() => import('./sections/proxy'));
 const AuthSection = lazy(() => import('./sections/auth-section'));
+const BackupsSection = lazy(() => import('./sections/backups-section'));
 
 // Inner component that uses context
 function SettingsPageInner() {
@@ -59,6 +60,7 @@ function SettingsPageInner() {
               {activeTab === 'globalenv' && <GlobalEnvSection />}
               {activeTab === 'proxy' && <ProxySection />}
               {activeTab === 'auth' && <AuthSection />}
+              {activeTab === 'backups' && <BackupsSection />}
             </Suspense>
           </div>
         </Panel>
diff --git a/ui/src/pages/settings/sections/backups-section.tsx b/ui/src/pages/settings/sections/backups-section.tsx
new file mode 100644
index 00000000..8d0ee98e
--- /dev/null
+++ b/ui/src/pages/settings/sections/backups-section.tsx
@@ -0,0 +1,237 @@
+/**
+ * Backups Section
+ * Settings section for managing config.yaml backups (list and restore)
+ */
+
+import { useEffect, useState, useCallback } from 'react';
+import { Button } from '@/components/ui/button';
+import { Alert, AlertDescription } from '@/components/ui/alert';
+import { ScrollArea } from '@/components/ui/scroll-area';
+import { Card } from '@/components/ui/card';
+import { Skeleton } from '@/components/ui/skeleton';
+import { Badge } from '@/components/ui/badge';
+import { RefreshCw, CheckCircle2, AlertCircle, RotateCcw, Clock, Archive } from 'lucide-react';
+import { useRawConfig } from '../hooks';
+
+interface Backup {
+  timestamp: string;
+  date: string;
+}
+
+interface BackupsResponse {
+  backups: Backup[];
+}
+
+export default function BackupsSection() {
+  const { fetchRawConfig } = useRawConfig();
+
+  // State
+  const [backups, setBackups] = useState<Backup[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [restoring, setRestoring] = useState<string | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  const [success, setSuccess] = useState<string | null>(null);
+
+  // Fetch backups
+  const fetchBackups = useCallback(async () => {
+    try {
+      setLoading(true);
+      setError(null);
+      const response = await fetch('/api/persist/backups');
+      if (!response.ok) {
+        throw new Error('Failed to fetch backups');
+      }
+      const data: BackupsResponse = await response.json();
+      setBackups(data.backups || []);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Unknown error');
+    } finally {
+      setLoading(false);
+    }
+  }, []);
+
+  // Restore backup
+  const restoreBackup = async (timestamp: string) => {
+    try {
+      setRestoring(timestamp);
+      setError(null);
+      const response = await fetch('/api/persist/restore', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ timestamp }),
+      });
+
+      if (!response.ok) {
+        const data = await response.json();
+        throw new Error(data.error || 'Failed to restore backup');
+      }
+
+      setSuccess('Backup restored successfully');
+      await fetchBackups();
+      await fetchRawConfig();
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Unknown error');
+    } finally {
+      setRestoring(null);
+    }
+  };
+
+  // Load on mount
+  useEffect(() => {
+    fetchBackups();
+  }, [fetchBackups]);
+
+  // Clear success after timeout
+  useEffect(() => {
+    if (success) {
+      const timer = setTimeout(() => setSuccess(null), 3000);
+      return () => clearTimeout(timer);
+    }
+  }, [success]);
+
+  // Clear error after timeout
+  useEffect(() => {
+    if (error) {
+      const timer = setTimeout(() => setError(null), 5000);
+      return () => clearTimeout(timer);
+    }
+  }, [error]);
+
+  // Loading skeleton
+  if (loading) {
+    return (
+      <>
+        <ScrollArea className="flex-1">
+          <div className="p-5 space-y-4">
+            <div className="space-y-2">
+              <Skeleton className="h-6 w-40" />
+              <Skeleton className="h-4 w-full" />
+            </div>
+            {[1, 2, 3].map((i) => (
+              <Card key={i} className="p-4">
+                <div className="flex items-center justify-between">
+                  <div className="space-y-2 flex-1">
+                    <Skeleton className="h-4 w-32" />
+                    <Skeleton className="h-3 w-48" />
+                  </div>
+                  <Skeleton className="h-8 w-20" />
+                </div>
+              </Card>
+            ))}
+          </div>
+        </ScrollArea>
+        <div className="p-4 border-t bg-background">
+          <Skeleton className="h-9 w-full" />
+        </div>
+      </>
+    );
+  }
+
+  return (
+    <>
+      {/* Toast-style alerts */}
+      <div
+        className={`absolute left-5 right-5 top-20 z-10 transition-all duration-200 ease-out ${
+          error || success
+            ? 'opacity-100 translate-y-0'
+            : 'opacity-0 -translate-y-2 pointer-events-none'
+        }`}
+      >
+        {error && (
+          <Alert variant="destructive" className="py-2 shadow-lg">
+            <AlertCircle className="h-4 w-4" />
+            <AlertDescription>{error}</AlertDescription>
+          </Alert>
+        )}
+        {success && (
+          <div className="flex items-center gap-2 px-3 py-2 rounded-md border border-green-200 bg-green-50 text-green-700 shadow-lg dark:border-green-900/50 dark:bg-green-900/90 dark:text-green-300">
+            <CheckCircle2 className="h-4 w-4 shrink-0" />
+            <span className="text-sm font-medium">{success}</span>
+          </div>
+        )}
+      </div>
+
+      {/* Scrollable Content */}
+      <ScrollArea className="flex-1">
+        <div className="p-5 space-y-4">
+          {/* Header */}
+          <div>
+            <div className="flex items-center gap-2 mb-2">
+              <Archive className="w-5 h-5 text-primary" />
+              <h2 className="text-lg font-semibold">Settings Backups</h2>
+            </div>
+            <p className="text-sm text-muted-foreground">
+              Restore previous versions of your config.yaml file. Backups are created automatically
+              when settings are modified.
+            </p>
+          </div>
+
+          {/* Backups List */}
+          {backups.length === 0 ? (
+            <Card className="p-8">
+              <div className="text-center">
+                <Archive className="w-12 h-12 mx-auto mb-3 opacity-30 text-muted-foreground" />
+                <p className="text-sm text-muted-foreground">No backups available</p>
+                <p className="text-xs text-muted-foreground mt-1">
+                  Backups will appear here when you modify settings
+                </p>
+              </div>
+            </Card>
+          ) : (
+            <div className="space-y-2">
+              {backups.map((backup, index) => (
+                <Card key={backup.timestamp} className="p-4 hover:bg-muted/50 transition-colors">
+                  <div className="flex items-center justify-between gap-4">
+                    <div className="flex items-start gap-3 flex-1 min-w-0">
+                      <Clock className="w-4 h-4 text-muted-foreground mt-0.5 shrink-0" />
+                      <div className="min-w-0 flex-1">
+                        <div className="flex items-center gap-2 mb-1">
+                          <p className="text-sm font-medium font-mono">{backup.timestamp}</p>
+                          {index === 0 && (
+                            <Badge variant="secondary" className="text-xs">
+                              Latest
+                            </Badge>
+                          )}
+                        </div>
+                        <p className="text-xs text-muted-foreground">{backup.date}</p>
+                      </div>
+                    </div>
+                    <Button
+                      variant="outline"
+                      size="sm"
+                      onClick={() => restoreBackup(backup.timestamp)}
+                      disabled={restoring !== null}
+                      className="gap-2 shrink-0"
+                    >
+                      <RotateCcw
+                        className={`w-4 h-4 ${restoring === backup.timestamp ? 'animate-spin' : ''}`}
+                      />
+                      {restoring === backup.timestamp ? 'Restoring...' : 'Restore'}
+                    </Button>
+                  </div>
+                </Card>
+              ))}
+            </div>
+          )}
+        </div>
+      </ScrollArea>
+
+      {/* Footer */}
+      <div className="p-4 border-t bg-background">
+        <Button
+          variant="outline"
+          size="sm"
+          onClick={() => {
+            fetchBackups();
+            fetchRawConfig();
+          }}
+          disabled={loading || restoring !== null}
+          className="w-full"
+        >
+          <RefreshCw className={`w-4 h-4 mr-2 ${loading ? 'animate-spin' : ''}`} />
+          Refresh
+        </Button>
+      </div>
+    </>
+  );
+}
diff --git a/ui/src/pages/settings/sections/proxy/index.tsx b/ui/src/pages/settings/sections/proxy/index.tsx
index a9807ec8..274ba607 100644
--- a/ui/src/pages/settings/sections/proxy/index.tsx
+++ b/ui/src/pages/settings/sections/proxy/index.tsx
@@ -3,16 +3,19 @@
  * Settings section for CLIProxyAPI configuration (local/remote)
  */
 
-import { useEffect } from 'react';
+import { useEffect, useState } from 'react';
 import { Button } from '@/components/ui/button';
 import { Alert, AlertDescription } from '@/components/ui/alert';
 import { ScrollArea } from '@/components/ui/scroll-area';
 import { Switch } from '@/components/ui/switch';
-import { RefreshCw, CheckCircle2, AlertCircle, Laptop, Cloud } from 'lucide-react';
+import { RefreshCw, CheckCircle2, AlertCircle, Laptop, Cloud, Bug } from 'lucide-react';
 import { useProxyConfig, useRawConfig } from '../../hooks';
 import { LocalProxyCard } from './local-proxy-card';
 import { RemoteProxyCard } from './remote-proxy-card';
 
+/** LocalStorage key for debug mode preference */
+const DEBUG_MODE_KEY = 'ccs_debug_mode';
+
 export default function ProxySection() {
   const {
     config,
@@ -39,6 +42,24 @@ export default function ProxySection() {
 
   const { fetchRawConfig } = useRawConfig();
 
+  // Debug mode state (persisted in localStorage)
+  const [debugMode, setDebugMode] = useState(() => {
+    try {
+      return localStorage.getItem(DEBUG_MODE_KEY) === 'true';
+    } catch {
+      return false;
+    }
+  });
+
+  const handleDebugModeChange = (enabled: boolean) => {
+    setDebugMode(enabled);
+    try {
+      localStorage.setItem(DEBUG_MODE_KEY, String(enabled));
+    } catch {
+      // Ignore storage errors
+    }
+  };
+
   // Load data on mount
   useEffect(() => {
     fetchConfig();
@@ -269,6 +290,35 @@ export default function ProxySection() {
             </div>
           </div>
 
+          {/* Advanced Settings */}
+          <div className="space-y-3">
+            <h3 className="text-base font-medium flex items-center gap-2">
+              <Bug className="w-4 h-4" />
+              Advanced
+            </h3>
+            <div className="space-y-3 p-4 rounded-lg border bg-muted/30">
+              {/* Debug Mode Toggle */}
+              <div className="flex items-center justify-between">
+                <div>
+                  <p className="font-medium text-sm">Debug Mode</p>
+                  <p className="text-xs text-muted-foreground">
+                    Show verbose logging and diagnostic info (--verbose)
+                  </p>
+                </div>
+                <Switch
+                  checked={debugMode}
+                  onCheckedChange={handleDebugModeChange}
+                  disabled={saving}
+                />
+              </div>
+              {debugMode && (
+                <p className="text-xs text-amber-600 dark:text-amber-400 pl-0.5">
+                  Debug mode enabled. Check browser console for detailed logs.
+                </p>
+              )}
+            </div>
+          </div>
+
           {/* Local Proxy Settings - Only show in Local mode */}
           {!isRemoteMode && (
             <LocalProxyCard
diff --git a/ui/src/pages/settings/types.ts b/ui/src/pages/settings/types.ts
index 9fdd73de..9e3ba4fc 100644
--- a/ui/src/pages/settings/types.ts
+++ b/ui/src/pages/settings/types.ts
@@ -49,7 +49,7 @@ export interface GlobalEnvConfig {
 
 // === Tab Types ===
 
-export type SettingsTab = 'websearch' | 'globalenv' | 'proxy' | 'auth';
+export type SettingsTab = 'websearch' | 'globalenv' | 'proxy' | 'auth' | 'backups';
 
 // === Re-exports from api-client ===