monzo-mcp
MCP server for the Monzo banking API. Read-only access to accounts, balances, pots, transactions, and spending analysis - all through Claude Code or any MCP client.
Unlike other Monzo MCP implementations that use raw bearer tokens (which expire in 6 hours), this server handles full OAuth with automatic token refresh.
Features
- 7 read-only tools - no write operations, no money movement
- OAuth with auto-refresh - tokens refresh automatically, no manual regeneration
- Local transaction cache - SQLite database survives Monzo's 90-day SCA window
- Spending analysis - category breakdowns, top merchants, month-over-month comparison
- Transaction search - search by merchant, description, or notes across cached history
Tools
| Tool | Description | Data source |
|---|---|---|
monzo_list_accounts | List accounts with types and IDs | Live API |
monzo_get_balance | Current balance and spend today | Live API |
monzo_list_pots | Savings pots and balances | Live API |
monzo_sync | Sync transactions to local cache | Live API -> SQLite |
monzo_list_transactions | List/filter cached transactions | Local cache |
monzo_search_transactions | Search by merchant/description/notes | Local cache |
monzo_spending | Spending analysis with category breakdown | Local cache |
Prerequisites
- Python 3.13+
- uv (recommended) or pip
- A Monzo account with an OAuth client registered at developers.monzo.com
Installation
git clone https://github.com/partymola/monzo-mcp.git
cd monzo-mcp
uv venv --python 3.13 .venv
uv pip install -e .
Setup
1. Register a Monzo OAuth client
Go to developers.monzo.com and create an OAuth client:
- Set the redirect URL to
http://localhost:6600/callback - Note your Client ID and Client Secret
2. Authenticate
monzo-mcp auth
This opens your browser for Monzo OAuth. After authorizing, approve the login in your Monzo app within 5 minutes for full transaction history access (Monzo's SCA window).
3. Register with Claude Code
claude mcp add -s user monzo -- /path/to/monzo-mcp/.venv/bin/monzo-mcp
4. First sync
In Claude Code, run monzo_sync to populate the local transaction cache. Do this immediately after auth to take advantage of the SCA window (up to 11 months of history).
Configuration
All configuration is via environment variables (optional):
| Variable | Default | Description |
|---|---|---|
MONZO_MCP_CONFIG_DIR | <package>/config/ | Directory for OAuth credentials and tokens |
MONZO_MCP_DB_PATH | <package>/monzo.db | Path to SQLite transaction cache |
Credential files (created by monzo-mcp auth):
config/monzo_client.json- OAuth client ID and secretconfig/monzo_tokens.json- Access and refresh tokens (auto-refreshed)
Monzo SCA window
Monzo's Strong Customer Authentication (SCA) limits transaction history access:
- Within 5 minutes of app approval: up to ~11 months of history
- After the window expires: only the last 90 days
The local SQLite cache preserves all synced transactions permanently, so run monzo_sync promptly after monzo-mcp auth.
Security
- Zero write tools - cannot send money, move funds between pots, or modify transactions
- Monzo API itself cannot send money to external accounts
- Tokens stored as JSON files in the
config/directory (gitignored) - All API calls are GET requests with Bearer token auth
License
GPL-3.0-or-later. See LICENSE.