LedgerLink MCP

An MCP server that connects AI assistants to QuickBooks Online. Manage invoices, customers, expenses, and reports through natural conversation.

"Show me all unpaid invoices" · "Create an invoice for Acme Corp for $5,000" · "What's my P&L for last quarter?"

What It Does

LedgerLink MCP gives AI assistants (Claude Desktop, Cursor, etc.) direct access to your QuickBooks Online data through the Model Context Protocol. Instead of clicking through the QuickBooks UI, you talk to your AI assistant in plain English.

32 tools across 10 QuickBooks entities:

Quick Start

1. Get QuickBooks Credentials

1. Create a free account at developer.intuit.com

2. Create an app → choose "QuickBooks Online and Payments"

3. Note your Client ID and Client Secret

4. Add http://localhost:3847/callback as a Redirect URI (under Settings)

2. Authenticate

# Clone and install
git clone https://github.com/YOUR_USERNAME/ledgerlink-mcp.git
cd ledgerlink-mcp
npm install

# Authenticate with QuickBooks (opens browser)
QB_CLIENT_ID=your_id QB_CLIENT_SECRET=your_secret npx tsx bin/cli.ts auth

A browser window opens → log in to QuickBooks → authorize → tokens are saved to ~/.ledgerlink/tokens.json.

3. Add to Claude Desktop

Edit your Claude Desktop config:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "ledgerlink": {
      "command": "npx",
      "args": ["tsx", "/path/to/ledgerlink-mcp/src/index.ts"],
      "env": {
        "QB_CLIENT_ID": "your_client_id",
        "QB_CLIENT_SECRET": "your_client_secret",
        "QB_ENVIRONMENT": "sandbox"
      }
    }
  }
}

Restart Claude Desktop. You'll see the tools icon — start talking to your books.

4. Try It

• "Show me all unpaid invoices"

• "Who owes me the most money?"

• "What's my profit and loss for 2024?"

• "Create an invoice for customer ID 1 for $500 consulting"

• "List all bills due this week"

How It Works

You: "Show me unpaid invoices"
  ↓
Claude Desktop → LedgerLink MCP (stdio) → QuickBooks API
  ↓
Claude: "You have 4 unpaid invoices totaling $3,200..."

LedgerLink runs as a local process. Claude Desktop spawns it, communicates over stdio (stdin/stdout), and your QuickBooks data never leaves your machine.

Configuration

Environment Variables

Token Storage

Tokens are stored in ~/.ledgerlink/tokens.json with owner-only permissions (chmod 600). Access tokens auto-refresh when expired (1-hour lifetime, 100-day refresh token).

Tool Reference

Invoices

• list_invoices — Filter by status (Unpaid/Paid/Overdue), customer, date range

• get_invoice — Full invoice details by ID

• create_invoice — Create with customer, line items, due date, memo

• send_invoice — Email an invoice to the customer

• void_invoice — Void an invoice (cannot be undone)

Customers

• list_customers — Search by name, filter active/inactive

• get_customer — Full customer details by ID

• create_customer — Create with name, email, phone, address

• update_customer — Update existing customer fields

Bills (Accounts Payable)

• list_bills — Filter by status, vendor, due date

• get_bill — Full bill details by ID

• create_bill — Create with vendor, line items, due date

Payments

• list_payments — Filter by date range, customer

• record_payment — Record payment, optionally applied to an invoice

Expenses

• list_expenses — Filter by date range, vendor

• get_expense — Full expense details by ID

• create_expense — Create with account, payment type, line items

Reports

• get_profit_and_loss — P&L for a date range, optionally by month/week

• get_balance_sheet — Balance sheet as of a date

• get_cash_flow — Cash flow statement for a date range

• get_aging_receivables — Who owes you, grouped by aging bucket

• get_aging_payables — What you owe, grouped by aging bucket

Chart of Accounts

• list_accounts — Filter by type (Bank, Expense, Income, etc.)

• get_account — Full account details by ID

• create_account — Create new account with type and sub-type

Vendors

• list_vendors — Search by name, filter active/inactive

• get_vendor — Full vendor details by ID

• create_vendor — Create with name, email, phone

Items (Products & Services)

• list_items — Search by name, filter by type (Service/Inventory)

• get_item — Full item details by ID

• create_item — Create with name, type, price, income account

Company

• get_company_info — Company name, address, fiscal year, currency

Development

# Install dependencies
npm install

# Run in development mode
QB_CLIENT_ID=xxx QB_CLIENT_SECRET=xxx npx tsx src/index.ts

# Test with MCP Inspector
QB_CLIENT_ID=xxx QB_CLIENT_SECRET=xxx npx @modelcontextprotocol/inspector npx tsx src/index.ts

# Type check
npx tsc --noEmit

# Build for distribution
npm run build

# Run tests
npm test

Architecture

src/
├── index.ts                 # Entry point — wires everything together
├── auth/
│   ├── oauth.ts             # OAuth 2.0 flow (local callback server)
│   └── token-store.ts       # Token persistence (~/.ledgerlink/)
├── quickbooks/
│   ├── client.ts            # HTTP client (auth, retry, rate limiting)
│   ├── types.ts             # TypeScript types for QB entities
│   ├── invoices.ts          # Invoice API operations
│   ├── customers.ts         # Customer API operations
│   └── ...                  # (10 entity modules total)
├── tools/
│   ├── invoice-tools.ts     # MCP tool registrations for invoices
│   ├── customer-tools.ts    # MCP tool registrations for customers
│   └── ...                  # (10 tool modules total)
├── resources/
│   └── index.ts             # MCP read-only resources
└── utils/
    ├── rate-limiter.ts      # Sliding window (450 req/min)
    ├── query-builder.ts     # QB query builder with sanitization
    └── formatters.ts        # Report response formatting

Security

• Tokens stored with chmod 600 (owner-only read/write)

• Client credentials passed via environment variables, never committed

• Query builder sanitizes all user input to prevent QB query injection

• All QuickBooks data stays local — no external servers, no telemetry

License

MIT