How to connect Claude to your accounting: KRONENWERK step by step

Connecting Claude to KRONENWERK is a sign-in, not a configuration. You add one address as a connector, Claude sends you to KRONENWERK, you sign in and confirm once, and from then on Claude reads your books and writes drafts into them for exactly the company you confirmed. This guide walks through it on the web, on the desktop app and on the phone, then through the first ten minutes of use: what to ask first, which level to leave the company on, and how to see and end the connection. ChatGPT and other assistants that speak MCP follow the same path with their own menu names.

Before you start

• A KRONENWERK company on the Enterprise plan or the practice plan — the MCP server belongs to those plans. Prices are on the pricing page.
• You are the owner of the company, or a member with the rights the assistant should inherit. An assistant connected by a bookkeeper sees what that bookkeeper sees, nothing more.
• A Claude account. Custom connectors are available in Claude on the web, in the desktop app and in the mobile apps; on a Team or Enterprise Claude plan an owner adds the connector for the organisation first.

Step 1 — add KRONENWERK as a connector

1. In Claude, open Customize → Connectors.
2. Choose Add custom connector.
3. Give it a name — "KRONENWERK" — and paste the address: https://kronenwerk.org/api/extern/mcp
4. Leave the advanced OAuth fields empty. KRONENWERK registers Claude as a client on its own (dynamic client registration) and publishes its authorization details under /.well-known/oauth-authorization-server, so nothing has to be typed.
5. Confirm with Add.

On a Team or Enterprise Claude plan the same form lives under Organization settings → Connectors; members then find KRONENWERK in their own connector list and press Connect.

Step 2 — sign in and confirm

Claude now opens KRONENWERK's sign-in page. Sign in as you always do — e-mail and password, Apple or Google. KRONENWERK shows a consent page naming the client, the company and the scopes the connection will hold: read customers, invoices, transactions and reports; write drafts. Confirm. Claude receives an OAuth 2.1 access token bound to that company; your password never leaves KRONENWERK, and Claude never sees it.

The consent page names the company you are signed into at that moment, and that is the company the connection will reach — if you own several, switch to the right one in KRONENWERK before you confirm. One connection reaches one company. To give Claude a second company, add a second connector — "KRONENWERK — Holding", say — and confirm it while signed into that company. There is no organisation parameter anywhere in the protocol, so a connection cannot switch companies later, by design.

Step 3 — choose the level

In KRONENWERK, open Settings → AI agent (MCP). The connection itself is listed under Settings → Integrations, with the client's name and the time it was confirmed; this page holds the level the company applies to every assistant:

• Read only — questions only.
• Read and propose — the default, and the right place to start. Claude drafts invoices and quotes, records supplier bills and receipts for your confirmation, creates jobs, files documents, writes notes. It cannot issue, send, or record a payment.
• Act within a limit — adds issuing, sending and recording payments, each up to the gross amount you set here.

Leave it at the default for the first weeks. The level is the company's, not the connection's: raising it later applies to every assistant and key at once.

Step 4 — enable the connector in a chat and ask

In a conversation, press the + at the lower left, open Connectors and switch KRONENWERK on. Then ask in plain language. Good first questions, because each one reads a different part of the books and shows you what the assistant can see:

• "What needs my attention this week?"
• "Who owes us money, and how overdue is it?"
• "Show me the Meyer transaction with everything attached."
• "Draft an invoice for job V2026-0142: 12 hours at 95 euro, standard VAT."
• "Record this bill" — with the supplier's PDF attached to the message.

Claude answers from what the tools return. A draft it makes is an ordinary draft: open it in KRONENWERK, check it, issue it. A bill it records waits in the inbox for your confirmation, with the file it came from attached.

Reading the authorship record

Under Settings → AI agent (MCP) every draft and every act carries the tool that made it, the connection and the time. Review it the way you would review a colleague's week. If you raise the level to Act within a limit, this is the page that tells you what was issued, sent and recorded without your hand on it.

Ending or replacing the connection

Under Settings → Integrations: Revoke. The token is refused on the assistant's next request; nothing is deleted from the books. On Claude's side, remove the connector under Customize → Connectors, or simply add it again and sign in anew to make a fresh connection — for instance after moving the company to a different owner.

ChatGPT and other assistants

ChatGPT connects to a custom MCP server through its connectors, with the same address and the same sign-in; the menu depends on your ChatGPT plan and workspace settings, and an administrator may have to allow custom connectors first. Agent frameworks and coding assistants that take a JSON configuration name the server by URL and send an API key instead of signing in — that path, with a copy-and-paste example, is in the developer documentation. Whichever client, the company's level applies, and the same authorship record fills.

When something does not work

The sign-in page does not appear

Check the address for a trailing character or a missing https://. The server answers a request without credentials with 401 and a pointer to its sign-in, which is what Claude follows; a wrong address reaches nothing.

"Plan does not include this"

The company is not on the Enterprise or practice plan. The refusal names the plan; the pricing page explains it.

Claude says a tool is not allowed

That is the level speaking, not a fault. The refusal names the setting a person would change. If you want the act, raise the level under Settings → AI agent (MCP); if not, the refusal is doing its job.

Claude sees the wrong company

The connection was confirmed for that company. Revoke it under Settings → Integrations, switch to the right company in KRONENWERK, and add the connector again.

How KRONENWERK handles this

SUPPORTED The MCP server accepts OAuth 2.1 sign-in with dynamic client registration, which is how Claude and ChatGPT connect without any manual credential; the company sets the level and the limit under Settings → AI agent (MCP); every connection is listed under Settings → Integrations and revocable there. The address, protocol revisions and tool list are described in the developer documentation; what an assistant can and cannot do is set out in the companion guide.