firma.de for Claude

Connect firma.de to Claude and ask about your books where you already work: what is still open for a month, which payments lack a receipt, or where an invoice is. Claude reads your bookkeeping with exactly the access you have in firma.de, and can add notes for your team and tax advisor when you allow it.

Requirements

A firma.de account with access to a company's bookkeeping, as Owner, Member or invited tax advisor, and a Claude plan that supports connectors.

Connect

  1. In Claude, open Customize → Connectors, find firma.de and select Connect.
  2. Sign in to firma.de with your usual login.
  3. On the consent screen, reading your bookkeeping is always included. Tick “Notizen hinzufügen” (add notes) only if Claude may add notes, then select “Erlauben” (allow).
  4. Back in Claude, ask about your bookkeeping. If you belong to several companies, Claude asks which one.

To add it by URL instead, choose Add custom connector and enter: https://app.firma.de/api/mcp

In Claude Code: claude mcp add --transport http firma https://app.firma.de/api/mcp, then run /mcp to sign in.

Things to ask

  • What's still missing for September in my company?
  • Which payments have no receipt yet?
  • Find my last Telekom invoice.
  • Show me the Hetzner payment from last week and add a note: this was our new office server.

Tools

list_companiesRead

The companies you belong to, your role, and whether bookkeeping is available.

get_bookkeeping_overviewRead

Where a month stands: period state, VAT return due date, open tasks by type, Vorsteuer (input VAT) held back, bank sync.

list_bookkeeping_tasksRead

The month's open tasks as your Tasks board shows them: what happened, why it matters, what resolves it, and a link.

search_documentsRead

Find invoices and receipts by vendor, date, amount, direction, status or text.

get_documentRead

One invoice: amounts, dates, review state, missing § 14 UStG fields, linked payments, notes, a short-lived link to the file.

search_transactionsRead

Find bank transactions by counterparty, date, amount, direction, account or status.

get_transactionRead

One payment: linked invoices, suggested matches, its history, notes, and the task it produces.

add_bookkeeping_noteWrite

Saves your explanation as a note on an invoice or payment. It never resolves a task and cannot be edited or deleted.

Every task comes with what happened, why it needs attention, the actions that resolve it and a link into firma.de. Booking, matching, uploading and filing stay in the app; the connector says which actions need it.

Permissions and safety

  • Claude acts as you: the same companies, roles and permissions as in firma.de. Each request is checked again, and the connection never gets more access than you have.
  • Two permissions: bookkeeping:read (always) and bookkeeping:notes (only if you tick it). There is no way to pay, book, file a VAT return or delete anything through the connector.
  • Text from invoices, bank purposes and notes is returned to Claude as untrusted data, marked as such, so that a document cannot instruct Claude to do anything.
  • A note is context for your team and tax advisor. It never closes a task: only the actual receipt, match or booking does.

Disconnect

In firma.de, open “Einstellungen → Verbundene Apps” (settings → connected apps) and select “Trennen” (disconnect). Access stops at once and every token issued to that connection is deleted. You can also remove the connector in Claude.

Privacy

This notice covers the connector and supplements the firma.de privacy policy. The controller is firma.de Firmenbaukasten GmbH.

  • What Claude can access: the bookkeeping data of the companies you belong to that you can see in firma.de, and only while the connection exists.
  • What firma.de stores: the connection itself (the app, the permissions you granted, when you connected) and its tokens, stored as hashes. Access tokens expire after one hour, refresh tokens after 30 days of disuse, and a connection after 180 days. Notes you add are stored on the invoice or payment like notes written in the app. For writes and refused requests, an audit record keeps who, which app, which company, which tool and records, and the outcome, never the content.
  • What firma.de does not store: your conversations or prompts. firma.de only receives the tool calls Claude makes and answers them.
  • Sharing: the answers to tool calls go to the assistant you connected, which processes them under its own terms (for Claude, Anthropic's). firma.de does not sell or share this data with anyone else.
  • Retention: the connection and its tokens are deleted when you disconnect or when they expire. Notes are part of the company's bookkeeping and are deleted with it. Audit records are deleted with your account.
  • Contact: support@firma.de

Support

Questions or problems with the connector: support@firma.de