Connect AI Assistants (MCP)

Use Claude, ChatGPT and other AI assistants with your LoanMonitor data: the two ways to connect, what each needs, and how to set it up.

LoanMonitor can be connected to AI assistants such as Claude and ChatGPT. Once connected, you can ask questions about your loans in plain language, or let the assistant do routine work for you.

Examples of what you can ask:

"Which loans mature in the next twelve months?"
"Show me the remaining balance and interest of all loans with Sparkasse."
"Summarize our portfolio by lender."
"Here is the bank's rate-fixing notice. Record it on the right loan."

The connection uses the Model Context Protocol (MCP), an open standard that lets AI assistants use external tools safely.

This page is an overview. When you are signed in to LoanMonitor, go to Settings → Access → MCP. There you find the exact values for your account, prefilled and ready to copy.

Your data stays protected

Your permissions apply. The assistant can never see or do more than you can in LoanMonitor. If you can only see certain locations, the assistant sees only those, too.
Read-only is possible. You decide whether the assistant may only read or also create and change data.
You can switch it off at any time, by removing the connector in your assistant or by revoking the API key in LoanMonitor.
Every change is logged. Changes made through an assistant appear in the loan's change history, just like changes made in the app.

Two ways to connect

There are two ways to connect. Which one fits depends on the app you use.

	Browser sign-in (OAuth)	API key
Works with	Claude (web, desktop and phone apps), ChatGPT (web and phone)	Claude Code, Claude Desktop, Cursor, VS Code, Windsurf, Codex CLI, Gemini CLI and other MCP clients
How you sign in	With your normal LoanMonitor login, in the browser	With an API key you create in LoanMonitor
What you install	Nothing	A small program that your app starts on your computer (requires Node.js 20 or newer)
Which customers	All customers your account has access to	Exactly one customer per key
Read-only	Do not grant "Write loans" when you sign in	Create a read-only key
Best for	Everyday questions in a chat	Developers, automation, desktop coding tools

Use one way per app. Do not set up both for the same assistant, or it will see every tool twice.

No installation and no key. You add LoanMonitor as a connector in your assistant and sign in with your usual LoanMonitor account.

The server address is:

https://api.loanmonitor.eu/mcp

Works on claude.ai and in the Claude desktop and phone apps. Custom connectors depend on your Claude plan.

On claude.ai, open Customize → Connectors and click Add custom connector.
Enter a name (for example LoanMonitor) and the server address above.
Under Advanced settings, enter the OAuth Client ID shown on the MCP page in LoanMonitor.
Click Add, then Connect. The LoanMonitor sign-in opens. Sign in and confirm the requested access.
Try it in a new chat: "List my loans."

Claude asks for write access only when you use a write action for the first time.

Works on chatgpt.com and in the ChatGPT phone app. It requires a plan that supports developer mode (Plus, Pro, Business, Enterprise or Education).

Turn on Developer mode once: Settings → Security and login → Developer mode.
Open chatgpt.com/plugins, click +, then Create app → Create MCP app.
Enter the server address above and choose OAuth as the authentication.
In the advanced OAuth settings, choose Custom OAuth client and fill in the values shown on the MCP page in LoanMonitor (client ID and scopes). Leave the client secret empty and switch OIDC enabled off.
Click Create. The LoanMonitor sign-in opens. Sign in and confirm the requested access.
Try it in a chat: "List my loans."

For read-only use, leave loans:write out of the scopes.

With browser sign-in the assistant acts as you, so it sees every customer you have access to. If you work for several customers, tell the assistant which one you mean.

Option 2: API key

Desktop and developer tools start a small LoanMonitor program on your computer. It is published on npm as @loanmonitor/mcp and connects to LoanMonitor with an API key.

Check Node.js. Run node --version in a terminal. You need version 20 or newer.

Create an API key. In LoanMonitor, open Settings → Access → API Keys and click Create key. Choose read-only for questions and reports, or read-write if the assistant should also create loans, record disbursements or rate fixings, or upload documents. The key is shown only once, so copy it right away.

Copy your values. The MCP page (Settings → Access → MCP) shows the three values your app needs: the API address, your key and your customer ID.

Add the server to your app. The MCP page has ready-made instructions for each app. Most apps use a configuration like the example below.

Restart your app completely (quit it, then start it again) and ask: "List my loans."

{
  "mcpServers": {
    "loanmonitor": {
      "command": "npx",
      "args": ["-y", "@loanmonitor/mcp"],
      "env": {
        "LOAN_MONITOR_API_URL": "https://api.loanmonitor.eu/api/v1",
        "LOAN_MONITOR_API_KEY": "lm_...",
        "LOAN_MONITOR_CUSTOMER_ID": "<your customer ID>"
      }
    }
  }
}

Treat an API key like a password. Do not share it, do not put it in shared project files, and revoke it in LoanMonitor if it may have leaked. Never make the local program reachable from the internet (for example through a tunnel): anyone who finds the address could then act with your key.

What the assistant can do

Area	Examples	Access needed
Loans	List and search loans, show details, repayment schedules and portfolio figures	Read
Master data	List locations, counterparties (banks, lenders) and bank accounts	Read
Documents	List the documents stored on a loan	Read
Planning	Calculate a repayment plan without saving it, to compare with the bank's plan	Read
Create and change	Create or correct loans, record disbursements, rate fixings and extra repayments, upload contracts and bank notices	Write
Documentation	Search and read this documentation	Browser sign-in only

Your own integrations

The API key also works for your own automation, for example with n8n or a script: send it in the X-API-Key header to the LoanMonitor API. A typical example is filing the bank's rate-fixing emails automatically. Planning an integration? Write to support@loanmonitor.eu; we are happy to help.

Troubleshooting

Problem	What to do
The assistant does not show the LoanMonitor tools	Restart the app completely. For browser sign-in, start a new chat.
"Unauthorized" or sign-in fails	Check that the API key is complete and not revoked. For browser sign-in, remove the connector and connect again.
"Customer mismatch"	The customer ID does not belong to the key. Copy both from the MCP page of the same account.
The assistant cannot create or change anything	The key is read-only, or write access was not granted at sign-in.
New features are missing	The assistant loads the tool list when a chat starts. Start a new chat or reconnect.

Still stuck? Write to support@loanmonitor.eu. Please never include your API key in the email.