feat(cliproxy): add account quota display for Antigravity provider

- Add quota-fetcher.ts for Google Cloud Code API integration
- Add REST endpoint GET /api/cliproxy/quota/:provider/:accountId
- Add useAccountQuota hook with React Query caching
- Display quota bar in AccountItem with per-model tooltip
- Create reusable Progress component
- Consolidate quota types in api-client.ts

src/cliproxy/index.ts

@@ -111,6 +111,10 @@ export {
 export type { CliproxyStats } from './stats-fetcher';
 export { fetchCliproxyStats, isCliproxyRunning } from './stats-fetcher';
 
+// Quota fetcher
+export type { ModelQuota, QuotaResult } from './quota-fetcher';
+export { fetchAccountQuota } from './quota-fetcher';
+
 // OpenAI compatibility layer
 export type { OpenAICompatProvider, OpenAICompatModel } from './openai-compat-manager';
 export {

src/cliproxy/quota-fetcher.ts

@@ -0,0 +1,313 @@
+/**
+ * Quota Fetcher for Antigravity Accounts
+ *
+ * Fetches quota information from Google Cloud Code internal API.
+ * Used for displaying remaining quota percentages and reset times.
+ */
+
+import * as fs from 'node:fs';
+import * as path from 'node:path';
+import { getAuthDir } from './config-generator';
+import { CLIProxyProvider } from './types';
+
+/** Individual model quota info */
+export interface ModelQuota {
+  /** Model name, e.g., "gemini-3-pro-high" */
+  name: string;
+  /** Display name from API, e.g., "Gemini 3 Pro" */
+  displayName?: string;
+  /** Remaining quota as percentage (0-100) */
+  percentage: number;
+  /** ISO timestamp when quota resets, null if unknown */
+  resetTime: string | null;
+}
+
+/** Quota fetch result */
+export interface QuotaResult {
+  /** Whether fetch succeeded */
+  success: boolean;
+  /** Quota for each available model */
+  models: ModelQuota[];
+  /** Timestamp of fetch */
+  lastUpdated: number;
+  /** True if account lacks quota access (403) */
+  isForbidden?: boolean;
+  /** Error message if fetch failed */
+  error?: string;
+}
+
+/** Google Cloud Code API endpoints */
+const ANTIGRAVITY_API_BASE = 'https://cloudcode-pa.googleapis.com';
+const ANTIGRAVITY_API_VERSION = 'v1internal';
+
+/** API client headers */
+const ANTIGRAVITY_HEADERS = {
+  'Content-Type': 'application/json',
+  'User-Agent': 'antigravity/1.11.5 linux/amd64',
+  'X-Goog-Api-Client': 'gl-node/20.9.0',
+};
+
+/** Auth file structure */
+interface AntigravityAuthFile {
+  access_token: string;
+  refresh_token?: string;
+  email?: string;
+  expired?: string;
+  expires_in?: number;
+  timestamp?: number;
+  type?: string;
+}
+
+/** loadCodeAssist response */
+interface LoadCodeAssistResponse {
+  cloudaicompanionProject?: string | { id?: string };
+}
+
+/** fetchAvailableModels response model */
+interface AvailableModel {
+  name?: string;
+  displayName?: string;
+  quotaInfo?: {
+    remainingFraction?: number;
+    remaining_fraction?: number;
+    remaining?: number;
+    resetTime?: string;
+    reset_time?: string;
+  };
+  quota_info?: {
+    remainingFraction?: number;
+    remaining_fraction?: number;
+    remaining?: number;
+    resetTime?: string;
+    reset_time?: string;
+  };
+}
+
+/** fetchAvailableModels response */
+interface FetchAvailableModelsResponse {
+  models?: Record<string, AvailableModel>;
+}
+
+/**
+ * Read access token from auth file
+ */
+function readAccessToken(provider: CLIProxyProvider, accountId: string): string | null {
+  const authDir = getAuthDir();
+
+  // Account ID format: email with @ and . replaced by _
+  // Try to find matching token file
+  const files = fs.readdirSync(authDir);
+  const prefix = provider === 'agy' ? 'antigravity-' : `${provider}-`;
+
+  for (const file of files) {
+    if (file.startsWith(prefix) && file.endsWith('.json')) {
+      // Check if this file matches the account ID
+      const baseName = file.replace(prefix, '').replace('.json', '');
+      if (baseName === accountId || file === accountId || file === `${accountId}.json`) {
+        const filePath = path.join(authDir, file);
+        try {
+          const content = fs.readFileSync(filePath, 'utf-8');
+          const data = JSON.parse(content) as AntigravityAuthFile;
+          return data.access_token || null;
+        } catch {
+          return null;
+        }
+      }
+    }
+  }
+
+  return null;
+}
+
+/**
+ * Get project ID via loadCodeAssist endpoint
+ */
+async function getProjectId(accessToken: string): Promise<string | null> {
+  const url = `${ANTIGRAVITY_API_BASE}/${ANTIGRAVITY_API_VERSION}:loadCodeAssist`;
+
+  const controller = new AbortController();
+  const timeoutId = setTimeout(() => controller.abort(), 5000);
+
+  try {
+    const response = await fetch(url, {
+      method: 'POST',
+      signal: controller.signal,
+      headers: {
+        ...ANTIGRAVITY_HEADERS,
+        Authorization: `Bearer ${accessToken}`,
+      },
+      body: JSON.stringify({
+        metadata: {
+          ideType: 'IDE_UNSPECIFIED',
+          platform: 'PLATFORM_UNSPECIFIED',
+          pluginType: 'GEMINI',
+        },
+      }),
+    });
+
+    clearTimeout(timeoutId);
+
+    if (!response.ok) {
+      return null;
+    }
+
+    const data = (await response.json()) as LoadCodeAssistResponse;
+
+    // Extract project ID from response
+    let projectId: string | undefined;
+    if (typeof data.cloudaicompanionProject === 'string') {
+      projectId = data.cloudaicompanionProject;
+    } else if (typeof data.cloudaicompanionProject === 'object') {
+      projectId = data.cloudaicompanionProject?.id;
+    }
+
+    return projectId?.trim() || null;
+  } catch {
+    clearTimeout(timeoutId);
+    return null;
+  }
+}
+
+/**
+ * Fetch available models with quota info
+ */
+async function fetchAvailableModels(accessToken: string, projectId: string): Promise<QuotaResult> {
+  const url = `${ANTIGRAVITY_API_BASE}/${ANTIGRAVITY_API_VERSION}:fetchAvailableModels`;
+
+  const controller = new AbortController();
+  const timeoutId = setTimeout(() => controller.abort(), 5000);
+
+  try {
+    const response = await fetch(url, {
+      method: 'POST',
+      signal: controller.signal,
+      headers: {
+        ...ANTIGRAVITY_HEADERS,
+        Authorization: `Bearer ${accessToken}`,
+      },
+      body: JSON.stringify({
+        project: projectId,
+      }),
+    });
+
+    clearTimeout(timeoutId);
+
+    if (response.status === 403) {
+      return {
+        success: false,
+        models: [],
+        lastUpdated: Date.now(),
+        isForbidden: true,
+        error: 'Quota access forbidden for this account',
+      };
+    }
+
+    if (response.status === 401) {
+      return {
+        success: false,
+        models: [],
+        lastUpdated: Date.now(),
+        error: 'Access token expired or invalid',
+      };
+    }
+
+    if (!response.ok) {
+      return {
+        success: false,
+        models: [],
+        lastUpdated: Date.now(),
+        error: `API error: ${response.status}`,
+      };
+    }
+
+    const data = (await response.json()) as FetchAvailableModelsResponse;
+    const models: ModelQuota[] = [];
+
+    if (data.models && typeof data.models === 'object') {
+      for (const [modelId, modelData] of Object.entries(data.models)) {
+        const quotaInfo = modelData.quotaInfo || modelData.quota_info;
+        if (!quotaInfo) continue;
+
+        // Extract remaining fraction (0-1 range)
+        const remaining =
+          quotaInfo.remainingFraction ?? quotaInfo.remaining_fraction ?? quotaInfo.remaining;
+
+        if (typeof remaining !== 'number') continue;
+
+        // Convert to percentage (0-100)
+        const percentage = Math.round(remaining * 100);
+
+        // Extract reset time
+        const resetTime = quotaInfo.resetTime || quotaInfo.reset_time || null;
+
+        models.push({
+          name: modelId,
+          displayName: modelData.displayName,
+          percentage,
+          resetTime,
+        });
+      }
+    }
+
+    return {
+      success: true,
+      models,
+      lastUpdated: Date.now(),
+    };
+  } catch (err) {
+    clearTimeout(timeoutId);
+    return {
+      success: false,
+      models: [],
+      lastUpdated: Date.now(),
+      error: err instanceof Error ? err.message : 'Unknown error',
+    };
+  }
+}
+
+/**
+ * Fetch quota for an Antigravity account
+ *
+ * @param provider - Provider name (only 'agy' supported)
+ * @param accountId - Account identifier (email with _ replacing @ and .)
+ * @returns Quota result with models and percentages
+ */
+export async function fetchAccountQuota(
+  provider: CLIProxyProvider,
+  accountId: string
+): Promise<QuotaResult> {
+  // Only Antigravity supports quota fetching
+  if (provider !== 'agy') {
+    return {
+      success: false,
+      models: [],
+      lastUpdated: Date.now(),
+      error: `Quota not supported for provider: ${provider}`,
+    };
+  }
+
+  // Read access token from auth file
+  const accessToken = readAccessToken(provider, accountId);
+  if (!accessToken) {
+    return {
+      success: false,
+      models: [],
+      lastUpdated: Date.now(),
+      error: 'Access token not found for account',
+    };
+  }
+
+  // Get project ID first
+  const projectId = await getProjectId(accessToken);
+  if (!projectId) {
+    return {
+      success: false,
+      models: [],
+      lastUpdated: Date.now(),
+      error: 'Failed to retrieve project ID',
+    };
+  }
+
+  // Fetch models with quota
+  return fetchAvailableModels(accessToken, projectId);
+}

src/web-server/routes/cliproxy-stats-routes.ts

@@ -12,6 +12,8 @@ import {
   fetchCliproxyErrorLogs,
   fetchCliproxyErrorLogContent,
 } from '../../cliproxy/stats-fetcher';
+import { fetchAccountQuota } from '../../cliproxy/quota-fetcher';
+import type { CLIProxyProvider } from '../../cliproxy/types';
 import {
   getCliproxyWritablePath,
   getConfigPath,
@@ -430,4 +432,50 @@ router.put('/models/:provider', async (req: Request, res: Response): Promise<voi
   }
 });
 
+// ==================== Account Quota ====================
+
+/**
+ * GET /api/cliproxy/quota/:provider/:accountId - Get quota for a specific account
+ * Returns: QuotaResult with model quotas and reset times
+ */
+router.get('/quota/:provider/:accountId', async (req: Request, res: Response): Promise<void> => {
+  const { provider, accountId } = req.params;
+
+  // Validate provider
+  const validProviders: CLIProxyProvider[] = [
+    'agy',
+    'gemini',
+    'codex',
+    'qwen',
+    'iflow',
+    'kiro',
+    'ghcp',
+  ];
+  if (!validProviders.includes(provider as CLIProxyProvider)) {
+    res.status(400).json({
+      error: 'Invalid provider',
+      message: `Provider must be one of: ${validProviders.join(', ')}`,
+    });
+    return;
+  }
+
+  // Validate accountId - prevent path traversal
+  if (
+    !accountId ||
+    accountId.includes('..') ||
+    accountId.includes('/') ||
+    accountId.includes('\\')
+  ) {
+    res.status(400).json({ error: 'Invalid account ID' });
+    return;
+  }
+
+  try {
+    const result = await fetchAccountQuota(provider as CLIProxyProvider, accountId);
+    res.json(result);
+  } catch (error) {
+    res.status(500).json({ error: (error as Error).message });
+  }
+});
+
 export default router;

ui/src/components/cliproxy/provider-editor/account-item.tsx

@@ -1,88 +1,195 @@
 /**
  * Account Item Component
- * Displays a single OAuth account with actions
+ * Displays a single OAuth account with actions and quota bar
  */
 
 import { Button } from '@/components/ui/button';
 import { Badge } from '@/components/ui/badge';
+import { Progress } from '@/components/ui/progress';
 import {
   DropdownMenu,
   DropdownMenuContent,
   DropdownMenuItem,
   DropdownMenuTrigger,
 } from '@/components/ui/dropdown-menu';
-import { User, Star, MoreHorizontal, Clock, Trash2 } from 'lucide-react';
+import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from '@/components/ui/tooltip';
+import { User, Star, MoreHorizontal, Clock, Trash2, Loader2 } from 'lucide-react';
 import { cn } from '@/lib/utils';
 import { PRIVACY_BLUR_CLASS } from '@/contexts/privacy-context';
+import { useAccountQuota } from '@/hooks/use-cliproxy-stats';
 import type { AccountItemProps } from './types';
 
+/**
+ * Format reset time as relative time (e.g., "in 2 hours")
+ */
+function formatResetTime(resetTime: string | null): string | null {
+  if (!resetTime) return null;
+  try {
+    const reset = new Date(resetTime);
+    const now = new Date();
+    const diff = reset.getTime() - now.getTime();
+    if (diff <= 0) return 'soon';
+
+    const hours = Math.floor(diff / (1000 * 60 * 60));
+    const minutes = Math.floor((diff % (1000 * 60 * 60)) / (1000 * 60));
+
+    if (hours > 0) return `in ${hours}h ${minutes}m`;
+    return `in ${minutes}m`;
+  } catch {
+    return null;
+  }
+}
+
+/**
+ * Get color class based on quota percentage
+ */
+function getQuotaColor(percentage: number): string {
+  if (percentage <= 20) return 'bg-destructive';
+  if (percentage <= 50) return 'bg-yellow-500';
+  return 'bg-green-500';
+}
+
 export function AccountItem({
   account,
   onSetDefault,
   onRemove,
   isRemoving,
   privacyMode,
+  showQuota,
 }: AccountItemProps) {
+  // Fetch quota for 'agy' provider accounts
+  const { data: quota, isLoading: quotaLoading } = useAccountQuota(
+    account.provider,
+    account.id,
+    showQuota && account.provider === 'agy'
+  );
+
+  // Calculate average quota across all models
+  const avgQuota =
+    quota?.success && quota.models.length > 0
+      ? Math.round(quota.models.reduce((sum, m) => sum + m.percentage, 0) / quota.models.length)
+      : null;
+
+  // Get earliest reset time
+  const nextReset =
+    quota?.success && quota.models.length > 0
+      ? quota.models.reduce(
+          (earliest, m) => {
+            if (!m.resetTime) return earliest;
+            if (!earliest) return m.resetTime;
+            return new Date(m.resetTime) < new Date(earliest) ? m.resetTime : earliest;
+          },
+          null as string | null
+        )
+      : null;
+
   return (
     <div
       className={cn(
-        'flex items-center justify-between p-3 rounded-lg border transition-colors',
+        'flex flex-col gap-2 p-3 rounded-lg border transition-colors',
         account.isDefault ? 'border-primary/30 bg-primary/5' : 'border-border hover:bg-muted/30'
       )}
     >
-      <div className="flex items-center gap-3">
-        <div
-          className={cn(
-            'flex items-center justify-center w-8 h-8 rounded-full',
-            account.isDefault ? 'bg-primary/10' : 'bg-muted'
-          )}
-        >
-          <User className="w-4 h-4" />
-        </div>
-        <div>
-          <div className="flex items-center gap-2">
-            <span className={cn('font-medium text-sm', privacyMode && PRIVACY_BLUR_CLASS)}>
-              {account.email || account.id}
-            </span>
-            {account.isDefault && (
-              <Badge variant="secondary" className="text-[10px] h-4 px-1.5 gap-0.5">
-                <Star className="w-2.5 h-2.5 fill-current" />
-                Default
-              </Badge>
+      <div className="flex items-center justify-between">
+        <div className="flex items-center gap-3">
+          <div
+            className={cn(
+              'flex items-center justify-center w-8 h-8 rounded-full',
+              account.isDefault ? 'bg-primary/10' : 'bg-muted'
+            )}
+          >
+            <User className="w-4 h-4" />
+          </div>
+          <div>
+            <div className="flex items-center gap-2">
+              <span className={cn('font-medium text-sm', privacyMode && PRIVACY_BLUR_CLASS)}>
+                {account.email || account.id}
+              </span>
+              {account.isDefault && (
+                <Badge variant="secondary" className="text-[10px] h-4 px-1.5 gap-0.5">
+                  <Star className="w-2.5 h-2.5 fill-current" />
+                  Default
+                </Badge>
+              )}
+            </div>
+            {account.lastUsedAt && (
+              <div className="flex items-center gap-1 text-xs text-muted-foreground mt-0.5">
+                <Clock className="w-3 h-3" />
+                Last used: {new Date(account.lastUsedAt).toLocaleDateString()}
+              </div>
             )}
           </div>
-          {account.lastUsedAt && (
-            <div className="flex items-center gap-1 text-xs text-muted-foreground mt-0.5">
-              <Clock className="w-3 h-3" />
-              Last used: {new Date(account.lastUsedAt).toLocaleDateString()}
-            </div>
-          )}
         </div>
+
+        <DropdownMenu>
+          <DropdownMenuTrigger asChild>
+            <Button variant="ghost" size="icon" className="h-7 w-7">
+              <MoreHorizontal className="w-4 h-4" />
+            </Button>
+          </DropdownMenuTrigger>
+          <DropdownMenuContent align="end">
+            {!account.isDefault && (
+              <DropdownMenuItem onClick={onSetDefault}>
+                <Star className="w-4 h-4 mr-2" />
+                Set as default
+              </DropdownMenuItem>
+            )}
+            <DropdownMenuItem
+              className="text-destructive focus:text-destructive"
+              onClick={onRemove}
+              disabled={isRemoving}
+            >
+              <Trash2 className="w-4 h-4 mr-2" />
+              {isRemoving ? 'Removing...' : 'Remove account'}
+            </DropdownMenuItem>
+          </DropdownMenuContent>
+        </DropdownMenu>
       </div>
 
-      <DropdownMenu>
-        <DropdownMenuTrigger asChild>
-          <Button variant="ghost" size="icon" className="h-7 w-7">
-            <MoreHorizontal className="w-4 h-4" />
-          </Button>
-        </DropdownMenuTrigger>
-        <DropdownMenuContent align="end">
-          {!account.isDefault && (
-            <DropdownMenuItem onClick={onSetDefault}>
-              <Star className="w-4 h-4 mr-2" />
-              Set as default
-            </DropdownMenuItem>
-          )}
-          <DropdownMenuItem
-            className="text-destructive focus:text-destructive"
-            onClick={onRemove}
-            disabled={isRemoving}
-          >
-            <Trash2 className="w-4 h-4 mr-2" />
-            {isRemoving ? 'Removing...' : 'Remove account'}
-          </DropdownMenuItem>
-        </DropdownMenuContent>
-      </DropdownMenu>
+      {/* Quota bar - only for 'agy' provider */}
+      {showQuota && account.provider === 'agy' && (
+        <div className="pl-11">
+          {quotaLoading ? (
+            <div className="flex items-center gap-2 text-xs text-muted-foreground">
+              <Loader2 className="w-3 h-3 animate-spin" />
+              <span>Loading quota...</span>
+            </div>
+          ) : avgQuota !== null ? (
+            <TooltipProvider>
+              <Tooltip>
+                <TooltipTrigger asChild>
+                  <div className="flex items-center gap-2">
+                    <Progress
+                      value={avgQuota}
+                      className="h-2 flex-1"
+                      indicatorClassName={getQuotaColor(avgQuota)}
+                    />
+                    <span className="text-xs font-medium w-10 text-right">{avgQuota}%</span>
+                  </div>
+                </TooltipTrigger>
+                <TooltipContent side="bottom" className="max-w-xs">
+                  <div className="text-xs space-y-1">
+                    <p className="font-medium">Model Quotas:</p>
+                    {quota?.models.map((m) => (
+                      <div key={m.name} className="flex justify-between gap-4">
+                        <span className="truncate">{m.displayName || m.name}</span>
+                        <span className="font-mono">{m.percentage}%</span>
+                      </div>
+                    ))}
+                    {nextReset && (
+                      <p className="text-muted-foreground mt-1">
+                        Resets {formatResetTime(nextReset)}
+                      </p>
+                    )}
+                  </div>
+                </TooltipContent>
+              </Tooltip>
+            </TooltipProvider>
+          ) : quota?.error ? (
+            <div className="text-xs text-muted-foreground">{quota.error}</div>
+          ) : null}
+        </div>
+      )}
     </div>
   );
 }

ui/src/components/cliproxy/provider-editor/accounts-section.tsx

@@ -16,6 +16,8 @@ interface AccountsSectionProps {
   onRemoveAccount: (accountId: string) => void;
   isRemovingAccount?: boolean;
   privacyMode?: boolean;
+  /** Show quota bars for accounts (only applicable for 'agy' provider) */
+  showQuota?: boolean;
 }
 
 export function AccountsSection({
@@ -25,6 +27,7 @@ export function AccountsSection({
   onRemoveAccount,
   isRemovingAccount,
   privacyMode,
+  showQuota,
 }: AccountsSectionProps) {
   return (
     <div>
@@ -54,6 +57,7 @@ export function AccountsSection({
               onRemove={() => onRemoveAccount(account.id)}
               isRemoving={isRemovingAccount}
               privacyMode={privacyMode}
+              showQuota={showQuota}
             />
           ))}
         </div>

ui/src/components/cliproxy/provider-editor/index.tsx

@@ -177,6 +177,7 @@ export function ProviderEditor({
                     onRemoveAccount={onRemoveAccount}
                     isRemovingAccount={isRemovingAccount}
                     privacyMode={privacyMode}
+                    provider={provider}
                   />
                 </TabsContent>
                 <TabsContent

ui/src/components/cliproxy/provider-editor/model-config-tab.tsx

@@ -35,6 +35,8 @@ interface ModelConfigTabProps {
   onRemoveAccount: (accountId: string) => void;
   isRemovingAccount?: boolean;
   privacyMode?: boolean;
+  /** Provider name for quota display */
+  provider?: string;
 }
 
 export function ModelConfigTab({
@@ -56,6 +58,7 @@ export function ModelConfigTab({
   onRemoveAccount,
   isRemovingAccount,
   privacyMode,
+  provider,
 }: ModelConfigTabProps) {
   return (
     <ScrollArea className="flex-1">
@@ -82,6 +85,7 @@ export function ModelConfigTab({
           onRemoveAccount={onRemoveAccount}
           isRemovingAccount={isRemovingAccount}
           privacyMode={privacyMode}
+          showQuota={provider === 'agy'}
         />
       </div>
     </ScrollArea>

ui/src/components/cliproxy/provider-editor/types.ts

@@ -35,6 +35,8 @@ export interface AccountItemProps {
   onRemove: () => void;
   isRemoving?: boolean;
   privacyMode?: boolean;
+  /** Show quota bar (only for 'agy' provider) */
+  showQuota?: boolean;
 }
 
 export interface ModelMappingValues {

ui/src/components/ui/progress.tsx

@@ -0,0 +1,40 @@
+/**
+ * Progress Component
+ * Simple progress bar with customizable indicator color
+ */
+
+import * as React from 'react';
+import { cn } from '@/lib/utils';
+
+interface ProgressProps extends React.HTMLAttributes<HTMLDivElement> {
+  value?: number;
+  max?: number;
+  indicatorClassName?: string;
+}
+
+const Progress = React.forwardRef<HTMLDivElement, ProgressProps>(
+  ({ className, value = 0, max = 100, indicatorClassName, ...props }, ref) => {
+    const percentage = Math.min(Math.max((value / max) * 100, 0), 100);
+
+    return (
+      <div
+        ref={ref}
+        role="progressbar"
+        aria-valuemin={0}
+        aria-valuemax={max}
+        aria-valuenow={value}
+        className={cn('relative h-2 w-full overflow-hidden rounded-full bg-secondary', className)}
+        {...props}
+      >
+        <div
+          className={cn('h-full transition-all', indicatorClassName || 'bg-primary')}
+          style={{ width: `${percentage}%` }}
+        />
+      </div>
+    );
+  }
+);
+
+Progress.displayName = 'Progress';
+
+export { Progress };

ui/src/hooks/use-cliproxy-stats.ts

@@ -3,6 +3,7 @@
  */
 
 import { useQuery } from '@tanstack/react-query';
+import type { ModelQuota, QuotaResult } from '@/lib/api-client';
 
 /** Per-account usage statistics */
 export interface AccountUsageStats {
@@ -189,3 +190,33 @@ export function useCliproxyErrorLogContent(name: string | null) {
     staleTime: 60000, // Cache log content for 1 minute
   });
 }
+
+// Re-export for consumers
+export type { ModelQuota, QuotaResult };
+
+/**
+ * Fetch account quota from API
+ */
+async function fetchAccountQuota(provider: string, accountId: string): Promise<QuotaResult> {
+  const response = await fetch(`/api/cliproxy/quota/${provider}/${encodeURIComponent(accountId)}`);
+  if (!response.ok) {
+    const error = await response.json();
+    throw new Error(error.message || 'Failed to fetch quota');
+  }
+  return response.json();
+}
+
+/**
+ * Hook to get account quota
+ * Only enabled for 'agy' provider (Antigravity) as it's the only one supporting quota
+ */
+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,
+    staleTime: 60000, // Cache for 1 minute
+    refetchInterval: 300000, // Refresh every 5 minutes
+    retry: 1,
+  });
+}

ui/src/lib/api-client.ts

@@ -107,6 +107,32 @@ export interface CliproxyModelsResponse {
   totalCount: number;
 }
 
+/** Individual model quota info from Google Cloud Code API */
+export interface ModelQuota {
+  /** Model name, e.g., "gemini-3-pro-high" */
+  name: string;
+  /** Display name from API, e.g., "Gemini 3 Pro" */
+  displayName?: string;
+  /** Remaining quota as percentage (0-100) */
+  percentage: number;
+  /** ISO timestamp when quota resets, null if unknown */
+  resetTime: string | null;
+}
+
+/** Quota fetch result */
+export interface QuotaResult {
+  /** Whether fetch succeeded */
+  success: boolean;
+  /** Quota for each available model */
+  models: ModelQuota[];
+  /** Timestamp of fetch */
+  lastUpdated: number;
+  /** True if account lacks quota access (403) */
+  isForbidden?: boolean;
+  /** Error message if fetch failed */
+  error?: string;
+}
+
 /** Provider accounts summary */
 export type ProviderAccountsMap = Record<string, OAuthAccount[]>;
 
@@ -404,4 +430,10 @@ export const api = {
         body: JSON.stringify(params),
       }),
   },
+  /** Account quota API */
+  quota: {
+    /** Fetch quota for a specific account */
+    get: (provider: string, accountId: string) =>
+      request<QuotaResult>(`/cliproxy/quota/${provider}/${encodeURIComponent(accountId)}`),
+  },
 };