Connect sevDesk to Claude

sevDesk has no MCP server of its own, but a REST API with an API token. Open-source servers build on it; XenMCP plans to run a reviewed one in an isolated sandbox.

Because this is accounting, the server starts read-only. You switch on write access deliberately, and your AI client asks before every change.

What you can ask Claude

• Which invoices are still unpaid?
• Show me all September vouchers over €500.
• How much has customer Weber paid in total this year?
• Which vouchers have no booking category yet?
• Create a contact for Neumann KG.

Typical tools

list_invoices

Find invoices by status and period

get_invoice

Read an invoice with its line items

list_vouchers

Search and filter vouchers

search_contacts

Find customers and suppliers

list_check_accounts

Show bank accounts and balances

create_contact

Create a contact (only with approval)

create_invoice_draft

Create a draft invoice (only with approval)

What you need to connect

• A sevDesk plan with API access – according to sevDesk help, from Buchhaltung Pro
• An API token (Settings → Users → API token), ideally from a dedicated user with limited rights
• A decision whether write access is needed (default: read-only)

Security

• The API token is stored encrypted with AES-256-GCM, never shown and never logged.
• The server starts read-only; write tools are a deliberate setting and ask before every change.
• Each server runs in its own sandbox (gVisor) in Germany; the call log holds only tool, status and duration.
• Accounting data contains personal data (GDPR). Your AI client processes the results in its own infrastructure.

Built on

We use the open server sevdesk-mcp (joosthel) (MIT), build the image ourselves from a pinned version and review the tool descriptions before release.

Frequently asked questions