Billingengine MCP

What billingengine-mcp MCP server does

billingengine-mcp MCP server exposes BillingEngine customer, invoicing, e-invoicing, and payment operations through MCP. It is intended for freelancers and small businesses using BillingEngine. The server communicates with the BillingEngine API while running on the local computer.

Customer operations include searching by company, name, or email, creating new customers, and changing existing customer records. Invoice operations cover creating draft invoices, editing drafts, filtering invoice lists, and retrieving a specific invoice with its line items and payment status. Payment operations can record a payment against a sent invoice or list payments, including payments associated with a particular invoice.

How it works

The MCP client sends tool requests to the local process, which passes supported operations to BillingEngine. New invoices remain drafts. The server does not send them to customers; they must be reviewed and sent in BillingEngine. Results include a link for opening the draft.

Invoice amounts are net, while numbering, language, invoice text, VAT handling, and payment terms follow the settings in the BillingEngine account. The download operation saves either a PDF invoice or an XML e-invoice to the computer's Downloads folder. BillingEngine supports e-invoicing formats including EN 16931, XRechnung, and ZUGFeRD / Factur-X.

Setup and configuration

billingengine-mcp MCP server requires Node.js 20 or later, a BillingEngine account on a paid plan, and an API key created under BillingEngine's Settings > API page. The Free plan does not provide API access.

For Claude Desktop and other stdio-capable clients, configure the process with npx -y billingengine-mcp and pass the API key through the environment. Claude Code can be configured with its MCP add command. Cursor uses the same command, arguments, and environment settings in its MCP configuration.

• BILLINGENGINE_API_KEY is required.
• BILLINGENGINE_URL changes the API base URL and defaults to https://www.billingengine.com.

The API key remains on the local computer and is sent only to BillingEngine. If it is exposed, replace it in BillingEngine; the old key stops working immediately.

Tools and capabilities

The available tools are:

• find_customers: search customers by company, name, or email.
• create_customer and update_customer: create or change customer records.
• create_invoice and update_invoice: create or edit draft invoices.
• list_invoices: filter invoices by status, customer, number, or date.
• get_invoice: retrieve invoice items and payment status.
• download_invoice: save a PDF or XML e-invoice locally.
• record_payment: record payments for sent invoices.
• list_payments: list payments, optionally for one invoice.

Limitations and notes

The server cannot delete records. Creating invoices counts toward the monthly invoice limit of the BillingEngine plan, and the API permits 60 requests per minute per key. Because invoice creation produces drafts only, sending remains a separate action in BillingEngine. BillingEngine itself is a commercial service, separate from this MIT-licensed server.