Connect ChatGPT
Set up Zahlenwerk as a custom MCP server in ChatGPT Business or Enterprise.
Requirements
Custom MCP servers with all tools are available in ChatGPT Business and Enterprise/Edu, on the web only. In Business, admins or owners set up the server; in Enterprise, also members the admins allow to. ChatGPT Pro can use Zahlenwerk read-only.
ChatGPT calls custom MCP servers plugins. The admin adds Zahlenwerk once and publishes it for the workspace. After that, each person signs in once with their own Zahlenwerk account the first time they use it.
Add the server
In ChatGPT, open Plugins, click + and choose Add custom MCP server. Name: Zahlenwerk, and under Connection the URL:
https://app.zahlenwerk.studio/api/mcpSet up sign-in
Choose OAuth. ChatGPT registers itself with Zahlenwerk; you don't need a client ID. Confirm the risk warning (I understand and want to continue) and choose Create as a plugin.
Sign in and test
ChatGPT opens Zahlenwerk in the browser. Sign in and approve the access. Then start a new chat, type @, pick Zahlenwerk and ask: "List my report collections in Zahlenwerk."
Publish for the workspace
Admins or owners publish the plugin in the admin console under PluginsManage Legacy AppsDraftsPublish. In Enterprise, that's also where you choose which tools and groups are allowed.
Good to know
- Chosen per message: ChatGPT only uses Zahlenwerk in the message where you pick it with @. Pick it again when you need new data.
- New tools: ChatGPT freezes the tool list when the plugin is published. When Zahlenwerk adds tools, the admin pulls them in with Refresh in the workspace settings.
- Write actions: ChatGPT asks for confirmation before changes, depending on the permissions set.
Disconnecting
In Zahlenwerk, under SettingsMCPConnected apps, click Revoke next to ChatGPT. That ends this person's access.