BillingEngine MCP

What you can do

The BillingEngine MCP server connects AI assistants such as Claude or Cursor to your account. You say what you need, the assistant does it with your BillingEngine data:

• Create an invoice for Malermeister Müller over 100 euros.
• Which invoices are overdue?
• Müller paid invoice 2610030028, record the payment.

Set up

You need Node.js 20 or newer, a BillingEngine account in a paid plan and your API key from Settings > API.

Claude Desktop: add the server to claude_desktop_config.json.

{
  "mcpServers": {
    "billingengine": {
      "command": "npx",
      "args": ["-y", "billingengine-mcp"],
      "env": { "BILLINGENGINE_API_KEY": "YOUR_API_KEY" }
    }
  }
}

Claude Code:

claude mcp add billingengine \
  --env BILLINGENGINE_API_KEY=YOUR_API_KEY \
  -- npx -y billingengine-mcp

Cursor and other MCP clients: use the same command, arguments and environment variable in the settings of the client.

The source code is open (MIT license) on GitHub.

Tools

Tool	Description
find_customers	Searches customers by company, name or email
create_customer	Creates a customer
update_customer	Changes a customer
create_invoice	Creates a draft invoice for a customer
update_invoice	Changes a draft invoice
list_invoices	Lists invoices, filtered by status, customer, number or date
get_invoice	Returns one invoice with its items and payment status
download_invoice	Saves the PDF or the XML e-invoice of an invoice on your computer
record_payment	Records a payment for sent invoices
list_payments	Lists payments, optionally for one invoice

What the server does not do

• It creates invoices as drafts. Nothing is sent to your customers; you review and send each invoice in BillingEngine.
• It cannot delete anything.
• It runs on your computer and talks to BillingEngine only with your API key. You can replace the key in your settings at any time; the settings also show when it was last used.
• New invoices count towards the monthly invoice maximum of your plan, and the API allows 60 requests per minute per key.