feat(cliproxy): add --use and --accounts flags for multi-account switching

- Add findAccountByQuery() to search accounts by nickname/email/id
- Add --accounts flag to list all accounts for a provider
- Add --use <name> flag to switch between accounts
- Filter CCS-specific flags from Claude CLI args
- Update help documentation with new multi-account commands

README.md

@@ -106,6 +106,29 @@ ccs agy --headless       # Displays URL, paste in browser elsewhere
 ccs gemini --logout
 ```
 
+### Multi-Account for OAuth Providers
+
+Use multiple accounts per provider (work + personal):
+
+```bash
+# First account (default)
+ccs gemini --auth
+
+# Add another account
+ccs gemini --auth --add
+
+# Add with nickname for easy identification
+ccs gemini --auth --add --nickname work
+
+# List all accounts
+ccs agy --accounts
+
+# Switch to a different account
+ccs agy --use work
+```
+
+Accounts are stored in `~/.ccs/cliproxy/accounts.json` and can be managed via web dashboard (`ccs config`).
+
 ### OAuth vs API Key Models
 
 | Feature | OAuth Providers<br>(gemini, codex, agy) | API Key Models<br>(glm, kimi) |

src/cliproxy/account-manager.ts

@@ -165,6 +165,32 @@ export function getAccount(provider: CLIProxyProvider, accountId: string): Accou
   return accounts.find((a) => a.id === accountId) || null;
 }
 
+/**
+ * Find account by query (nickname, email, or id)
+ * Supports partial matching for convenience
+ */
+export function findAccountByQuery(provider: CLIProxyProvider, query: string): AccountInfo | null {
+  const accounts = getProviderAccounts(provider);
+  const lowerQuery = query.toLowerCase();
+
+  // Exact match first (id, email, nickname)
+  const exactMatch = accounts.find(
+    (a) =>
+      a.id === query ||
+      a.email?.toLowerCase() === lowerQuery ||
+      a.nickname?.toLowerCase() === lowerQuery
+  );
+  if (exactMatch) return exactMatch;
+
+  // Partial match on nickname or email prefix
+  const partialMatch = accounts.find(
+    (a) =>
+      a.nickname?.toLowerCase().startsWith(lowerQuery) ||
+      a.email?.toLowerCase().startsWith(lowerQuery)
+  );
+  return partialMatch || null;
+}
+
 /**
  * Register a new account
  * Called after successful OAuth to record the account

src/cliproxy/cliproxy-executor.ts

@@ -28,6 +28,12 @@ import { isAuthenticated } from './auth-handler';
 import { CLIProxyProvider, ExecutorConfig } from './types';
 import { configureProviderModel, getCurrentModel } from './model-config';
 import { supportsModelConfig, isModelBroken, getModelIssueUrl, findModel } from './model-catalog';
+import {
+  findAccountByQuery,
+  getProviderAccounts,
+  setDefaultAccount,
+  touchAccount,
+} from './account-manager';
 
 /** Default executor configuration */
 const DEFAULT_CONFIG: ExecutorConfig = {
@@ -124,6 +130,52 @@ export async function execClaudeWithCLIProxy(
   const forceLogout = args.includes('--logout');
   const forceConfig = args.includes('--config');
   const addAccount = args.includes('--add');
+  const showAccounts = args.includes('--accounts');
+
+  // Parse --use <account> flag
+  let useAccount: string | undefined;
+  const useIdx = args.indexOf('--use');
+  if (useIdx !== -1 && args[useIdx + 1] && !args[useIdx + 1].startsWith('-')) {
+    useAccount = args[useIdx + 1];
+  }
+
+  // Handle --accounts: list accounts and exit
+  if (showAccounts) {
+    const accounts = getProviderAccounts(provider);
+    if (accounts.length === 0) {
+      console.log(`[i] No accounts registered for ${providerConfig.displayName}`);
+      console.log(`    Run "ccs ${provider} --auth" to add an account`);
+    } else {
+      console.log(`\n${providerConfig.displayName} Accounts:\n`);
+      for (const acct of accounts) {
+        const defaultMark = acct.isDefault ? ' (default)' : '';
+        const nickname = acct.nickname ? `[${acct.nickname}]` : '';
+        console.log(`  ${nickname.padEnd(12)} ${acct.email || acct.id}${defaultMark}`);
+      }
+      console.log(`\n  Use "ccs ${provider} --use <nickname>" to switch accounts`);
+    }
+    process.exit(0);
+  }
+
+  // Handle --use: switch to specified account
+  if (useAccount) {
+    const account = findAccountByQuery(provider, useAccount);
+    if (!account) {
+      console.error(`[X] Account not found: "${useAccount}"`);
+      const accounts = getProviderAccounts(provider);
+      if (accounts.length > 0) {
+        console.error(`    Available accounts:`);
+        for (const acct of accounts) {
+          console.error(`      - ${acct.nickname || acct.id} (${acct.email || 'no email'})`);
+        }
+      }
+      process.exit(1);
+    }
+    // Set as default for this and future sessions
+    setDefaultAccount(provider, account.id);
+    touchAccount(provider, account.id);
+    console.log(`[OK] Switched to account: ${account.nickname || account.email || account.id}`);
+  }
 
   // Handle --config: configure model selection and exit
   // Pass customSettingsPath for CLIProxy variants to save to correct file
@@ -262,8 +314,14 @@ export async function execClaudeWithCLIProxy(
   log(`Claude env: ANTHROPIC_MODEL=${envVars.ANTHROPIC_MODEL}`);
 
   // Filter out CCS-specific flags before passing to Claude CLI
-  const ccsFlags = ['--auth', '--headless', '--logout', '--config', '--add'];
-  const claudeArgs = args.filter((arg) => !ccsFlags.includes(arg));
+  const ccsFlags = ['--auth', '--headless', '--logout', '--config', '--add', '--accounts', '--use'];
+  const claudeArgs = args.filter((arg, idx) => {
+    // Filter out CCS flags
+    if (ccsFlags.includes(arg)) return false;
+    // Filter out value after --use
+    if (args[idx - 1] === '--use') return false;
+    return true;
+  });
 
   const isWindows = process.platform === 'win32';
   const needsShell = isWindows && /\.(cmd|bat|ps1)$/i.test(claudeCli);

src/commands/cliproxy-command.ts

@@ -656,6 +656,21 @@ async function showHelp(): Promise<void> {
   }
   console.log('');
 
+  // Multi-Account Commands
+  console.log(subheader('Multi-Account Commands:'));
+  const multiAcctCmds: [string, string][] = [
+    ['--auth', 'Authenticate with a provider (first account)'],
+    ['--auth --add', 'Add another account to a provider'],
+    ['--nickname <name>', 'Set friendly name for account'],
+    ['--accounts', 'List all accounts for a provider'],
+    ['--use <name>', 'Switch to account by nickname/email'],
+  ];
+  const maxMultiLen = Math.max(...multiAcctCmds.map(([cmd]) => cmd.length));
+  for (const [cmd, desc] of multiAcctCmds) {
+    console.log(`  ${color(cmd.padEnd(maxMultiLen + 2), 'command')} ${desc}`);
+  }
+  console.log('');
+
   // Create Options
   console.log(subheader('Create Options:'));
   const createOpts: [string, string][] = [
@@ -690,6 +705,23 @@ async function showHelp(): Promise<void> {
     `  $ ${color('ccs cliproxy --latest', 'command')}                   ${dim('# Update binary')}`
   );
   console.log('');
+  console.log(subheader('Multi-Account Examples:'));
+  console.log(
+    `  $ ${color('ccs gemini --auth', 'command')}                       ${dim('# First account')}`
+  );
+  console.log(
+    `  $ ${color('ccs gemini --auth --add', 'command')}                 ${dim('# Add second account')}`
+  );
+  console.log(
+    `  $ ${color('ccs gemini --auth --add --nickname work', 'command')} ${dim('# With nickname')}`
+  );
+  console.log(
+    `  $ ${color('ccs agy --accounts', 'command')}                      ${dim('# List accounts')}`
+  );
+  console.log(
+    `  $ ${color('ccs agy --use work', 'command')}                      ${dim('# Switch account')}`
+  );
+  console.log('');
 
   // Notes
   console.log(subheader('Notes:'));

src/commands/help-command.ts

@@ -162,6 +162,8 @@ Claude Code Profile & Model Switcher`.trim();
       ['', ''], // Spacer
       ['ccs <provider> --auth', 'Authenticate only'],
       ['ccs <provider> --auth --add', 'Add another account'],
+      ['ccs <provider> --accounts', 'List all accounts'],
+      ['ccs <provider> --use <name>', 'Switch to account'],
       ['ccs <provider> --config', 'Change model (agy, gemini)'],
       ['ccs <provider> --logout', 'Clear authentication'],
       ['ccs <provider> --headless', 'Headless auth (for SSH)'],