Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type @ followed by the MCP server name and your instructions, e.g., "@lexoffice-mcp Create a draft invoice for Bike & Ride GmbH: 8 hours consulting at 120 EUR net plus 19% VAT"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
MCP server (built with FastMCP) for creating invoices in Lexware Office (formerly lexoffice).
Tool | Purpose |
| Creates an invoice. Drafts by default; |
| Looks up customers by name, email or customer number to reference them via |
| Returns the full invoice (line items, totals, status). |
create_invoice supports one-time addresses or existing contacts, custom, service, material and text
line items, net, gross and vat-free tax types, performance dates and periods, payment terms with early
payment discount, and title, introduction and remark texts. It returns the invoice id, number, status,
totals and deep links into Lexware.
The client respects the Lexware limit of 2 requests per second and retries 429 responses. Other errors
are not retried, so a failing request never creates duplicate invoices.
Related MCP server: sevdesk MCP Server
Ask Claude something like:
Create a draft invoice for Bike & Ride GmbH, Musterstraße 42, 79112 Freiburg, Germany: 8 hours of consulting at 120 EUR net with 19% VAT, payable within 14 days.
Claude calls create_invoice with a payload such as:
{
"invoice": {
"address": { "name": "Bike & Ride GmbH", "street": "Musterstraße 42", "zip": "79112", "city": "Freiburg", "country_code": "DE" },
"line_items": [
{ "name": "Consulting", "quantity": 8, "unit_name": "Stunde", "unit_price": 120, "tax_rate_percentage": 19 }
],
"payment_conditions": { "payment_term_label": "Zahlbar innerhalb von 14 Tagen", "payment_term_duration": 14 }
}
}and gets back the invoice number, totals and a link to open the draft in Lexware.
Create an API key at https://app.lexware.de/addons/public-api.
Clone this repository. No install step is needed: uv run --with resolves the dependencies
(fastmcp, httpx) on the fly when the server starts.
Run the server manually to check it starts:
LEXWARE_API_KEY=your-api-key uv run --with "fastmcp>=4" --with httpx /absolute/path/to/lexoffice_mcp/main.pyclaude mcp add lexware --scope user \
-e LEXWARE_API_KEY=your-api-key \
-- uv run --with "fastmcp>=4" --with httpx /absolute/path/to/lexoffice_mcp/main.pyCheck the connection with claude mcp list or /mcp inside Claude Code. The key is stored in plain text in
your Claude Code configuration, so use a key dedicated to this integration and revoke it when no longer needed.
Add to claude_desktop_config.json:
{
"mcpServers": {
"lexware": {
"command": "uv",
"args": ["run", "--with", "fastmcp>=4", "--with", "httpx", "/absolute/path/to/lexoffice_mcp/main.py"],
"env": { "LEXWARE_API_KEY": "your-api-key" }
}
}
}Variable | Default | Description |
| required | Lexware public API key. |
|
| API gateway. |
|
| Used for invoice deep links. |
uv sync
uv run pytestTests run the server in memory against a mocked Lexware API, so no API key is needed.
MIT, see LICENSE.
This server cannot be deployed
Compliant invoicing for freelancers: create, issue and track invoices from your AI agent.
Spanish Veri*factu invoicing: create invoices, expenses and VAT returns from your AI assistant.
German e-invoicing: generate XRechnung 3.0, pre-check and extract (incl. ZUGFeRD PDF). Paid.
Create, send and track invoices for freelancers and small businesses.
