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AI

Your invoices, controlled by your AI assistant

Ask your AI assistant to create an invoice, send reminders or give you a VAT overview. EenFactuurMaken.nl has an MCP server, a REST API and a site that AIs can read easily.

Connect the MCP serverSee the prompts

Works with

  • ChatGPT
  • Claude
  • Cursor
  • Gemini CLI
  • Copilot (VS Code)

Just ask

What you can ask

Just in your own words.

  • “Create an invoice for Bakkerij De Vries for 12 hours of web design.”
  • “Send reminders for all overdue invoices.”
  • “Make a VAT overview for Q3.”
  • “Turn these spreadsheet rows into invoice lines.”

Go to the prompt library

  • You Which invoices are still open with customers in Germany?
  • Assistant Two: 2026-0038 to Müller GmbH (€2,400, 9 days overdue) and 2026-0041 to Kaffeehaus Lenz (€640, due Friday). Shall I send Müller a reminder in German?
Terminal
# Fetch all open invoices
curl https://eenfactuurmaken.nl/api/v1/invoices?status=open \
  -H "Authorization: Bearer efm_…"

{ "data": [ … ], "total": 2 }

Open standards

Built to connect

Not a closed app, but open standards.

  • MCP server

    The Model Context Protocol. Your assistant gets tools for customers, products and invoices.

  • REST API

    Anything the app can do, the API can too. With API keys, on every plan.

  • llms.txt

    An overview of the site for AIs, with links to all key pages.

  • Prompt library

    Ready-made prompts to copy, or to open directly in ChatGPT or Claude.

  • OpenAPI spec

    Have your AI generate a client in your programming language.

Connect safely

You stay in control

An AI assistant is handy, but an invoice is a legal document.

  • You decide which assistant gets access, and you can revoke that access any time.

  • Our prompts have the assistant create a draft first and ask for your approval before anything is issued or sent.

  • The same checks as in the app: an invoice missing mandatory details can't be issued through AI either.

  • You see API keys once and never paste them into a chat. Your assistant signs in through the connection itself.

Why no AI in your invoices?

We don't let AI write your invoices

EenFactuurMaken.nl itself doesn't use AI to generate text or amounts on your invoices. There are good reasons for that.

  • Privacy

    Your invoices contain your customers' data. We don't send it to an AI service. If you connect an assistant yourself, you choose which one.

  • Accuracy

    A language model can get an amount or a VAT rate wrong. On an invoice, that's not acceptable. What's on it, you entered or confirmed.

  • Predictable

    VAT, totals and numbering are calculated with fixed rules. The same input always gives the same invoice.

Try it with your own assistant

Create a free account, create an API key or connect the MCP server, and ask your assistant for your first invoice.

Start for freeConnect the MCP server