Multi-Account Management

The NotebookLM MCP server supports multiple Google accounts with automatic rotation when rate limits are hit.

Overview

NotebookLM has a 50 queries per day limit per Google account (free tier). With multi-account support, the server can automatically switch to another account when the limit is reached, giving you up to 150 queries/day with 3 accounts.

Architecture

┌─────────────────────────────────────────────────────────────┐
│                    Account Manager                          │
├─────────────────────────────────────────────────────────────┤
│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐      │
│  │  Account 1   │  │  Account 2   │  │  Account 3   │      │
│  │  (Primary)   │  │  (Secondary) │  │  (Tertiary)  │      │
│  │  50/day      │  │  50/day      │  │  50/day      │      │
│  └──────────────┘  └──────────────┘  └──────────────┘      │
│                                                             │
│  Rotation Strategy: least_used | round_robin | failover    │
└─────────────────────────────────────────────────────────────┘

Configuration

Account Directory Structure

Each account has its own directory under DATA_DIR/accounts/:

DATA_DIR/
├── accounts/
│   ├── account-{timestamp1}/
│   │   ├── config.json      # Account configuration
│   │   ├── quota.json       # Usage tracking
│   │   ├── state.json       # Account state
│   │   ├── browser_state/
│   │   │   └── state.json   # Playwright storage state
│   │   └── profile/         # Chrome profile directory
│   │
│   ├── account-{timestamp2}/
│   │   └── ...
│   │
│   └── config.json          # Global accounts config
│
├── browser_state/
│   └── state.json           # Active account's state
│
└── chrome_profile/          # Active account's Chrome profile

Account Config File

accounts/account-{id}/config.json:

{
  "id": "account-1766565732376",
  "email": "user@gmail.com",
  "enabled": true,
  "priority": 1,
  "totp_secret": "BASE32SECRET..." // Optional for 2FA
}

Quota Tracking

accounts/account-{id}/quota.json:

{
  "used": 15,
  "limit": 50,
  "resetAt": "2025-12-31T00:00:00.000Z",
  "lastUpdated": "2025-12-30T10:00:00.000Z"
}

Global Config

accounts/config.json:

{
  "rotationStrategy": "least_used",
  "autoRotateOnRateLimit": true,
  "maxConsecutiveFailures": 3
}

Rotation Strategies

least_used (Default)

Selects the account with the most remaining quota. Best for maximizing throughput.

round_robin

Cycles through accounts in order. Best for even distribution.

failover

Uses accounts in priority order. Only switches when current account fails.

Rate Limit Detection

The server detects rate limits via:

1. Response text: "Le système n'a pas pu répondre" (general error)
2. Input field: "Vous avez atteint la limite quotidienne de discussions"
3. Page body: Rate limit keywords in French/English

Detection Keywords

French:

• "limite quotidienne de discussions"
• "atteint la limite quotidienne"
• "vous avez atteint la limite"
• "revenez plus tard"

English:

• "daily limit reached"
• "rate limit exceeded"
• "quota exhausted"
• "too many requests"

Automatic Rotation Flow

When a rate limit is detected:

1. Rate limit detected
   ↓
2. Mark current account as quota exhausted
   ↓
3. Close browser sessions (releases profile lock)
   ↓
4. Wait 2 seconds for Chrome to release files
   ↓
5. Select next available account (based on strategy)
   ↓
6. Sync new account's profile to main profile:
   - Copy state.json → browser_state/
   - Copy profile/ → chrome_profile/
   ↓
7. Retry the request with new account

Adding a New Account

Via CLI

npm run accounts add

Follow the interactive prompts to:

1. Enter email address
2. Enter password
3. Optionally enter TOTP secret for 2FA

Manually

1. Create account directory:

   mkdir -p DATA_DIR/accounts/account-$(date +%s)

2. Create config.json:

   {
     "id": "account-...",
     "email": "newaccount@gmail.com",
     "enabled": true,
     "priority": 2
   }

3. Run auto-login to authenticate:

   npm run accounts test account-... -- --show

4. Sync to main profile if this should be the active account.

CLI Commands

# List all accounts
npm run accounts list

# Add new account
npm run accounts add

# Test account authentication
npm run accounts test <account-id> -- --show

# Remove account
npm run accounts remove <account-id>

Troubleshooting

All Accounts Exhausted

If all accounts hit their daily limit:

1. Wait until midnight UTC for quotas to reset
2. Manually reset quotas for testing:

   echo '{"used": 0, "limit": 50, ...}' > accounts/account-xxx/quota.json

Account Won't Switch

Check if:

1. Profile lock is released (close all Chrome instances)
2. Account has quota remaining
3. Account is enabled in config.json
4. Account hasn't exceeded failure threshold

Authentication Expired

Re-authenticate the account:

npm run accounts test <account-id> -- --show

Then sync to main profile if needed.

API Integration

The /ask endpoint automatically handles account rotation. No changes needed to API calls.

If rotation fails, the response includes:

{
  "success": false,
  "error": "NotebookLM rate limit reached... Automatic account rotation failed..."
}

Language Switching

Each account may have a different Google Account language setting. The server uses UI selectors that must match the NotebookLM language.

Automated Language Switch

Use the provided script to switch an account's language:

./scripts/switch-account-language.sh --account=account-b --lang=fr --show

What it does:

1. Stops the server and Chrome
2. Deletes the Chrome profile cache for the account
3. Re-authenticates (opens browser for login)
4. Syncs the new profile to main
5. Restarts server with the correct NOTEBOOKLM_UI_LOCALE

Important: The Google Account's language setting must match. Change it at: https://myaccount.google.com/language

Environment Variable

Set the UI locale when starting the server:

NOTEBOOKLM_UI_LOCALE=en node dist/http-wrapper.js

See Adding a Language for details on the i18n system.

---

Best Practices

1. Use 3+ accounts for production workloads
2. Enable TOTP for unattended authentication
3. Monitor quotas via logs or quota.json files
4. Stagger usage across accounts to avoid hitting limits simultaneously
5. Test rotation before deploying to production
6. Match UI locale with each account's Google language setting