Skip to content
NederlandsLog inStart for free

Connecting ChatGPT

Add EenFactuurMaken.nl as a connector in ChatGPT (developer mode) and sign in with OAuth. Then create invoices in a chat.

ChatGPT connects with OAuth: you sign in to EenFactuurMaken.nl and give permission. You don't need an API key.

Steps

  1. Open ChatGPT in your browser and go to Settings → Apps & Connectors → Advanced settings.
  2. Turn on Developer mode.
  3. Choose Create connector (or "Create").
  4. Fill in:
    • Name: EenFactuurMaken.nl
    • MCP server URL: https://eenfactuurmaken.nl/mcp
    • Authentication: OAuth
  5. Click Create. A EenFactuurMaken.nl window opens: sign in (with 2FA if you have it on) and click Allow.
  6. Start a new chat, pick your EenFactuurMaken.nl connector in the tools menu and ask something, for example: "How many invoices are outstanding?"

Menu names change now and then. Can't find it? Search the settings for "connector" or "MCP".

Good to know

  • Developer mode and custom connectors aren't available on every ChatGPT plan. Check with OpenAI which plans support it.
  • ChatGPT asks for confirmation before using a tool that changes or sends something.
  • The connection appears under Settings → API & AI → Connected apps in EenFactuurMaken.nl. You disconnect it there too.

Not working? See MCP server: troubleshooting.

Last updated on 13 October 2026

Stuck?

Email us at support@eenfactuurmaken.nl. Tell us what you tried and what happened, and we will help you out.

support@eenfactuurmaken.nl