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# Lexware Office (lexoffice) API and MCP server

> Yes, Lexware Office has a public REST API with an API key (checked 14 Oct 2026). It covers quotes, order confirmations, invoices, contacts, file uploads, payments (read only) and webhooks, but only from version XL, and Lexware publishes no MCP server of its own. You generate the key yourself, and the API cannot change an invoice once it is finalised.

German cloud accounting and invoicing software from Haufe Group for freelancers and small businesses: quotes, invoices, payment reminders, receipt capture, contacts and bookkeeping in one browser account.

## What is the Lexware Office (lexoffice) API?

Cotlet's Lexware Office (lexoffice) API exposes 14 endpoints for your own Lexware Office (lexoffice) account: list documents, get document, list contacts, list receipts, download document PDF, create contact, create invoice, create quote, finalise document, send document, record payment, send payment reminder, cancel invoice and upload receipt. The list_documents endpoint returns invoices, quotes, order confirmations and delivery notes, filtered by type and status. Each endpoint takes simple JSON inputs like document_id, contact_id or limit and works both as an operation of the lexware_office_read or lexware_office_write MCP tool for agents and as a REST call for scripts.

- **Category:** [Invoicing & freelance CRM](https://cotlet.dev/integrations/category/invoicing-freelance-crm.md)
- **Endpoints:** 14 (5 read, 9 write)
- **Updated:** 2026-10-21

Yes, Lexware Office has a public REST API with an API key (checked 14 Oct 2026). Cotlet is a hosted MCP server and REST API for Lexware Office (lexoffice) with 14 endpoints (5 read, 9 write): you sign in once in your own cloud browser, your AI agent does the work.

## Does Lexware Office (lexoffice) have an official API?

Yes, Lexware Office has a public REST API with an API key (checked 14 Oct 2026). It covers quotes, order confirmations, invoices, contacts, file uploads, payments (read only) and webhooks, but only from version XL, and Lexware publishes no MCP server of its own. You generate the key yourself, and the API cannot change an invoice once it is finalised.

| Task | Lexware Office (lexoffice) official | Cotlet |
|---|---|---|
| Create draft invoices | Yes: Invoices are created as drafts by default; XL only | Yes |
| Finalise an invoice | Partly: Only at creation with finalize=true; the status cannot be changed through the API afterwards | Yes |
| Send an invoice or quote by email | No | Yes |
| Create quotes | Yes: Draft or finalised; XL only | Yes |
| Upload receipts for bookkeeping | Yes: The files endpoint with type voucher; the file lands in the unchecked folder "Zu prüfen" | Yes |
| Add contacts | Partly: One contact person, one billing and one shipping address when created through the API | Yes |
| Record a payment on an invoice | No: The payments endpoint is read access to payment status only | Yes |
| Cancel a finalised invoice | No: The status of an invoice cannot be changed via the API | Yes |

Sources: [Lexware Office Public API](https://www.lexware.de/funktionen/public-api/), [Lexware Office API documentation](https://developers.lexware.io/docs/), [Lexware Office Public API license and terms of use](https://agb.lexware.de/lexware-office/public-api-lizenz--und-nutzungsbedingungen), [Lexware Office prices and versions](https://www.lexware.de/preise/)

## For AI agents

```text
Yes, Lexware Office has a public REST API with an API key (checked 14 Oct 2026). It covers quotes, order confirmations, invoices, contacts, file uploads, payments (read only) and webhooks, but only from version XL, and Lexware publishes no MCP server of its own. You generate the key yourself, and the API cannot change an invoice once it is finalised.
Cotlet provides a hosted MCP server and REST API for Lexware Office (lexoffice): 14 tools (5 read, 9 write).
Access       Sign up at https://cotlet.dev/app/signup?app=lexware-office, then request the app and create API keys in the Cotlet console.

MCP server   https://cotlet.dev/mcp/v1
MCP tools    lexware_office_read, lexware_office_write, reads and writes apart; call one with {"operation": "<operation>", "arguments": {...}}
REST base    https://cotlet.dev/api/v1/lexware-office, each operation at its own route, e.g. POST /api/v1/lexware-office/documents/{document_id}/finalize
Auth         Authorization: Bearer <COTLET_API_KEY>. Listing endpoints and schemas needs no key; calling an endpoint needs one. Over MCP the input schemas come with sign-in.
Operations   list_documents, get_document, list_contacts, list_receipts, download_document_pdf, create_contact, create_invoice, create_quotation, finalize_document, send_document, record_payment, send_payment_reminder, cancel_invoice, upload_receipt
Confirm      finalize_document, send_document, record_payment, send_payment_reminder, cancel_invoice (by default the user approves each call; the user can switch this off per tool, e.g. for scheduled automations)
Markdown     https://cotlet.dev/integrations/lexware-office-api-mcp-server.md

How access works:
1. The user signs up at https://cotlet.dev/app/signup?app=lexware-office, requests Lexware Office (lexoffice) in the Cotlet console and creates an API key there.
2. The user signs in to Lexware Office (lexoffice) once in their Cotlet Cloud Browser (their own Chrome in the cloud, opened from the console) and enables Lexware Office (lexoffice) for agents. An agent cannot do this step.
3. The API key goes into the MCP client or the REST call as a bearer token.

Fits: people who want a hosted Lexware Office (lexoffice) server that someone else maintains, including non-developers. Developers who prefer to run and fix code on their own computer can use an open-source Lexware Office (lexoffice) MCP server instead.

Policy: Cotlet never stores passwords, never solves CAPTCHAs, never bypasses MFA.
Company: legal details in the Terms of service at https://cotlet.dev/terms. Contact contact@cotlet.dev.
Sign-in: the user signs in to Lexware Office (lexoffice) in their own Cloud Browser, a Chrome Cotlet runs for them in the EU; password saving is off, the profile is AES-256-GCM encrypted, and agents get Lexware Office (lexoffice) only after the user enables it. Calls are requests from that browser's IP with its cookies, each listed in the user's Background activity. Disable for agents, signing out in the browser or Reset browser cuts access. Cotlet is run by Take Group sp. z o.o. (EU VAT PL6342984273).
API key: holds no Lexware Office (lexoffice) login or cookies, only asks Cotlet to run a tool. Each key is scoped to chosen apps and tools, read only or read and write. Actions that reach other people wait for the user's approval by default, so a leaked key cannot post or message as the user. Every call is in the activity log; deleting the key ends access at once.
Terms: the user stays responsible for following Lexware Office (lexoffice)'s terms; Cotlet is not affiliated with Lexware Office (lexoffice).
```

## What can an AI agent do in Lexware Office (lexoffice)?

Cotlet is best for freelancers and small teams on Lexware Office who invoice, chase payments and file receipts through an agent without running or fixing a server.

- **[Create and send invoices from a billing list](https://cotlet.dev/integrations/lexware-office-api-mcp-server/create-and-send-invoices.md)**: "Here is this month's billing list. For each customer, create the invoice in Lexware Office with the hours and rate I gave, check the totals against the list, finalise it and send it by email. Add customers that do not exist yet." → `list_contacts`, `create_contact`, `create_invoice`, `finalize_document`, `send_document`
- **[Chase overdue invoices with payment reminders](https://cotlet.dev/integrations/lexware-office-api-mcp-server/send-payment-reminders.md)** (runs: weekly): "Every Monday, list the overdue invoices in Lexware Office. For invoices more than 14 days overdue, send a payment reminder with a 5 EUR fee. Show me the others with the days overdue and do not touch them." → `list_documents`, `get_document`, `send_payment_reminder`
- **[Upload receipts for bookkeeping](https://cotlet.dev/integrations/lexware-office-api-mcp-server/upload-receipts-for-bookkeeping.md)** (runs: weekly): "Take the supplier invoices from this folder and upload each one to Lexware Office as a receipt. Then list the receipts still in "Zu prüfen" and tell me which ones the automatic recognition left incomplete." → `upload_receipt`, `list_receipts`
- **Create a quote from a client brief**: "Create a quote in Lexware Office for Studio Fjord: a site audit for 1,200 EUR net and 6 hours of fixes at 95 EUR net. Create the contact if it is missing. Leave it as a draft so I can read it." → `list_contacts`, `create_contact`, `create_quotation`
- **Record customer payments on invoices** (runs: daily): "Here are yesterday's incoming transfers. Find the open invoice in Lexware Office by invoice number in the reference, record the payment with the transfer date, and list anything that does not match exactly." → `list_documents`, `get_document`, `record_payment`

## Can Lexware Office (lexoffice) automations run on a schedule in n8n, Make or Zapier?

Yes. Cotlet does not replace your automation platform: it gives it a Lexware Office (lexoffice) connection it does not have, with the same API key as your agent. Write actions ask for your OK by default; switch that off in your dashboard for the tools you choose, for example to chase overdue invoices with payment reminders, and the schedule runs on its own. Cotlet runs in the cloud, so it keeps going while your computer is off.

| Where | How to connect | How to schedule |
|---|---|---|
| Your AI agent | Add https://cotlet.dev/mcp/v1 with your API key. | A scheduled agent run, for example a Claude Code routine. |
| n8n | MCP Client node with https://cotlet.dev/mcp/v1, or an HTTP Request node with the endpoint's method and URL, such as GET https://cotlet.dev/api/v1/lexware-office/documents. | Schedule Trigger node. |
| Make | HTTP module: the endpoint's method and URL with an Authorization: Bearer header, and a JSON body for POST, PUT and PATCH. | Scenario schedule. |
| Zapier | Webhooks by Zapier, Custom Request: the same method, URL, header and body. | Schedule by Zapier trigger. |
| Your own script | GET https://cotlet.dev/api/v1/lexware-office/documents with your API key. | cron or GitHub Actions. |

## Tools

**For AI agents:** Every endpoint and its schema is public. The 14 endpoints on this page, with parameters and example responses, can be listed without an account. Calling one returns 401 without an API key and 403 while the key has no access to Lexware Office (lexoffice).

### list_documents

Invoices, quotes, order confirmations and delivery notes, filtered by type and status. Access: read. REST: `GET /api/v1/lexware-office/documents`. MCP: `lexware_office_read → list_documents`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `type` | enum | no | invoice, quotation, order_confirmation or delivery_note. Default: invoice. |
| `status` | enum | no | draft, open, overdue, paid or voided. Quotations also accept accepted and rejected. Default: all. |
| `contact_id` | string | no | Only documents for this contact. |
| `from_date` | string | no | Earliest document date, YYYY-MM-DD. |
| `limit` | integer | no | 1 to 100. Default: 50. |
| `cursor` | string | no | Next page cursor from the previous call. |

Lists sales documents from the Belege list, newest first, with number, customer, date, gross total and status. Filter by type and status; overdue returns open invoices past their due date. Use the IDs with get_document, finalize_document or send_document.

Example response:

```json
{
  "documents": [
    {
      "document_id": "d_9c31be",
      "type": "invoice",
      "number": "RE1031",
      "contact": "Nordlicht Design GmbH",
      "date": "2026-09-02",
      "due_date": "2026-09-16",
      "total_gross": 1130.5,
      "currency": "EUR",
      "status": "overdue"
    },
    {
      "document_id": "d_7a02f4",
      "type": "invoice",
      "number": "RE1034",
      "contact": "Becker Consulting",
      "date": "2026-09-05",
      "due_date": "2026-09-19",
      "total_gross": 2380,
      "currency": "EUR",
      "status": "overdue"
    }
  ],
  "next_cursor": null
}
```

### get_document

One document with its lines, totals, status and reminders already sent. Access: read. REST: `GET /api/v1/lexware-office/documents/{document_id}`. MCP: `lexware_office_read → get_document`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `document_id` | string | yes | Document ID from list_documents or create_invoice. |

Returns one invoice or quote: customer, dates, line items, net, tax and gross totals, status, open amount and the reminders already sent. A draft has no number yet; the number appears when the document is finalised.

Example response:

```json
{
  "document_id": "d_9c31be",
  "type": "invoice",
  "number": "RE1031",
  "status": "overdue",
  "contact": {
    "contact_id": "c_4f2a91",
    "name": "Nordlicht Design GmbH",
    "email": "buchhaltung@nordlicht.example"
  },
  "date": "2026-09-02",
  "due_date": "2026-09-16",
  "lines": [
    {
      "name": "Consulting, September",
      "quantity": 10,
      "unit_price_net": 95,
      "tax_rate": 19
    }
  ],
  "total_net": 950,
  "total_tax": 180.5,
  "total_gross": 1130.5,
  "open_amount": 1130.5,
  "currency": "EUR",
  "reminders": []
}
```

### list_contacts

Customers and suppliers saved in Lexware Office, searchable by name or email. Access: read. REST: `GET /api/v1/lexware-office/contacts`. MCP: `lexware_office_read → list_contacts`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `query` | string | no | Part of a name, email address or customer number. |
| `role` | enum | no | customer or vendor. Default: both. |
| `limit` | integer | no | 1 to 100. Default: 50. |
| `cursor` | string | no | Next page cursor from the previous call. |

Searches the saved contacts by name, email or customer number and returns the ID, role, billing address and email. Einmalkontakte, the one-off names kept only on a document, are not saved contacts and do not appear here.

Example response:

```json
{
  "contacts": [
    {
      "contact_id": "c_4f2a91",
      "name": "Nordlicht Design GmbH",
      "role": "customer",
      "customer_number": "10042",
      "email": "buchhaltung@nordlicht.example",
      "city": "Hamburg"
    }
  ],
  "next_cursor": null
}
```

### list_receipts

Receipts in Lexware Office with the fields the automatic recognition filled in. Access: read. REST: `GET /api/v1/lexware-office/receipts`. MCP: `lexware_office_read → list_receipts`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `status` | enum | no | to_check or all. Default: all. |
| `from_date` | string | no | Earliest receipt date, YYYY-MM-DD. |
| `limit` | integer | no | 1 to 100. Default: 50. |
| `cursor` | string | no | Next page cursor from the previous call. |

Lists uploaded receipts with their status, contact, receipt number, date and amount as the automatic recognition read them. Use status to_check to see receipts that still wait for Beleg erfassen. Fields the recognition could not fill are returned as null.

Example response:

```json
{
  "receipts": [
    {
      "receipt_id": "r_21b8c0",
      "file_name": "Hetzner-2026-10.pdf",
      "status": "to_check",
      "contact": "Hetzner Online GmbH",
      "receipt_number": "R0023981",
      "date": "2026-10-01",
      "amount_gross": 24.99,
      "currency": "EUR"
    },
    {
      "receipt_id": "r_21b8c1",
      "file_name": "scan-0417.pdf",
      "status": "to_check",
      "contact": null,
      "receipt_number": null,
      "date": "2026-10-09",
      "amount_gross": null,
      "currency": "EUR"
    }
  ],
  "next_cursor": null
}
```

### download_document_pdf

The PDF of a finalised invoice or quote. Access: read. REST: `GET /api/v1/lexware-office/documents/{document_id}/pdf/download`. MCP: `lexware_office_read → download_document_pdf`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `document_id` | string | yes | Document ID from list_documents or create_invoice. |

Returns a download link for the PDF Lexware Office generated when the document was finalised. A draft has no PDF; use get_document to read it instead. For an e-invoice in XRechnung format the document is an XML file, and the link points to that file.

Example response:

```json
{
  "document_id": "d_9c31be",
  "number": "RE1031",
  "file_name": "RE1031.pdf",
  "download_url": "https://files.example.com/f_3b90aa/RE1031.pdf"
}
```

### create_contact

Save a new customer or supplier in Lexware Office. Access: write. REST: `POST /api/v1/lexware-office/contacts`. MCP: `lexware_office_write → create_contact`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `name` | string | yes | Company name, or a person's full name. |
| `role` | enum | no | customer or vendor. Default: customer. |
| `email` | string | no | Email address used by send_document. |
| `street` | string | no | Street and house number. |
| `postal_code` | string | no | Postal code. |
| `city` | string | no | City. |
| `country` | string | no | Two-letter country code. Default: DE. |

Saves a contact in your master data; Lexware Office creates a debtor or creditor account for it and suggests it on future documents. It reaches no one and is undone by archiving or deleting the contact in the app, so it does not ask for your OK.

Example response:

```json
{
  "contact_id": "c_88d0e1",
  "name": "Studio Fjord",
  "role": "customer",
  "customer_number": "10057",
  "email": "hallo@studiofjord.example"
}
```

### create_invoice

Save a draft invoice for a contact. Nothing is sent and no number is assigned yet. Access: write. REST: `POST /api/v1/lexware-office/contacts/{contact_id}/invoices`. MCP: `lexware_office_write → create_invoice`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `contact_id` | string | yes | Contact ID from list_contacts or create_contact. |
| `invoice_date` | string | yes | Invoice date, YYYY-MM-DD. |
| `lines` | array | yes | Line items. Each has name, quantity, unit_price_net (EUR) and tax_rate (percent, as offered in your Lexware Office tax settings). Free-text lines need only a name. |
| `delivery_date` | string | no | Delivery or service date, YYYY-MM-DD. |
| `payment_term_days` | integer | no | Days until the invoice is due. Default: your Lexware Office payment terms. |
| `intro_text` | string | no | Introduction text above the lines. |

Saves an invoice as a draft, the state Lexware Office keeps editable until finalised. The draft has no invoice number, reaches no customer and is deleted with one call in the app, so it does not ask for your OK. Returns net, tax and gross totals so you can check them before finalize_document.

Example response:

```json
{
  "document_id": "d_c44e19",
  "type": "invoice",
  "number": null,
  "status": "draft",
  "contact": {
    "contact_id": "c_4f2a91",
    "name": "Nordlicht Design GmbH"
  },
  "date": "2026-10-14",
  "due_date": "2026-10-28",
  "lines": [
    {
      "name": "Consulting, October",
      "quantity": 10,
      "unit_price_net": 95,
      "tax_rate": 19
    }
  ],
  "total_net": 950,
  "total_tax": 180.5,
  "total_gross": 1130.5,
  "currency": "EUR"
}
```

### create_quotation

Save a draft quote for a contact. Nothing is sent. Access: write. REST: `POST /api/v1/lexware-office/contacts/{contact_id}/quotations`. MCP: `lexware_office_write → create_quotation`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `contact_id` | string | yes | Contact ID from list_contacts or create_contact. |
| `quotation_date` | string | yes | Quote date, YYYY-MM-DD. |
| `lines` | array | yes | Line items. Each has name, quantity, unit_price_net (EUR) and tax_rate (percent, as offered in your Lexware Office tax settings). Free-text lines need only a name. |
| `valid_until` | string | no | Last day the quote is valid, YYYY-MM-DD. |
| `intro_text` | string | no | Introduction text above the lines. |

Saves a quote (Angebot) as a draft. It has no number yet, reaches no customer and is deleted with one call in the app, so it does not ask for your OK. Returns the totals so you can read them before finalize_document.

Example response:

```json
{
  "document_id": "d_e5120a",
  "type": "quotation",
  "number": null,
  "status": "draft",
  "contact": {
    "contact_id": "c_88d0e1",
    "name": "Studio Fjord"
  },
  "date": "2026-10-14",
  "lines": [
    {
      "name": "Site audit",
      "quantity": 1,
      "unit_price_net": 1200,
      "tax_rate": 19
    },
    {
      "name": "Fixes, hours",
      "quantity": 6,
      "unit_price_net": 95,
      "tax_rate": 19
    }
  ],
  "total_net": 1770,
  "total_tax": 336.3,
  "total_gross": 2106.3,
  "currency": "EUR"
}
```

### finalize_document

Finalise a draft invoice or quote: it gets its number and can no longer be edited. Access: write, asks the user first. REST: `POST /api/v1/lexware-office/documents/{document_id}/finalize`. MCP: `lexware_office_write → finalize_document`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `document_id` | string | yes | Document ID from list_documents or create_invoice. |

Clicks Abschließen on a draft. The invoice or quote gets its final number from your number range, appears in the list as open, and a PDF is generated. A finalised invoice is legally binding and cannot be edited; the only way back is cancel_invoice, which blocks the number for good. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "document_id": "d_c44e19",
  "type": "invoice",
  "number": "RE1043",
  "status": "open",
  "total_gross": 1130.5,
  "currency": "EUR"
}
```

### send_document

Email a finalised invoice or quote to the customer with its PDF attached. Access: write, asks the user first. REST: `POST /api/v1/lexware-office/documents/{document_id}`. MCP: `lexware_office_write → send_document`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `document_id` | string | yes | Document ID from list_documents or create_invoice. |
| `to` | string | no | Recipient email. Default: the email saved on the contact. |
| `message` | string | no | Email text. Default: your saved email text template. |

Sends the finalised document from your own sender address with your email text template, to the email address saved on the contact or the one you pass. A draft cannot be sent. The customer receives it at once. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "document_id": "d_c44e19",
  "number": "RE1043",
  "sent_to": "buchhaltung@nordlicht.example",
  "sent_at": "2026-10-14T09:12:00+02:00"
}
```

### record_payment

Record a customer payment on an open invoice. Access: write, asks the user first. REST: `POST /api/v1/lexware-office/documents/{document_id}/payments`. MCP: `lexware_office_write → record_payment`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `document_id` | string | yes | Document ID from list_documents or create_invoice. |
| `amount` | number | yes | Amount received in EUR. |
| `payment_date` | string | yes | Date the money arrived, YYYY-MM-DD. |
| `payment_type` | enum | no | private or cash. Cash only if a cash book is set up; otherwise private. Default: private. |

Clicks Zahlung erfassen on the invoice with the amount, the payment date and the payment type. The invoice drops out of the open and overdue lists once the open amount is paid. A payment recorded by hand is removed with the trash icon in the invoice details, but users with the restricted role "Belege, Kontakte & Produkte" cannot delete payments. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "document_id": "d_9c31be",
  "number": "RE1031",
  "amount": 1130.5,
  "payment_date": "2026-10-13",
  "payment_type": "private",
  "open_amount": 0,
  "currency": "EUR"
}
```

### send_payment_reminder

Send a Mahnung or Zahlungserinnerung for an overdue invoice, with an optional fee. Access: write, asks the user first. REST: `POST /api/v1/lexware-office/documents/{document_id}/payment-reminders`. MCP: `lexware_office_write → send_payment_reminder`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `document_id` | string | yes | Document ID from list_documents or create_invoice. |
| `fee_amount` | number | no | Reminder fee in EUR, added as an item of type Mahngebühr. Default: no fee. |
| `intro_text` | string | no | Introduction text of the reminder. Default: your saved text. |

Opens Mahnen on the invoice, uses your saved reminder text, adds a Mahngebühr line when you pass a fee and sends the reminder by email. It works only for invoices created in Lexware Office, not imported ones. The customer receives it at once, and the reminder then appears in the Mahnungen section of the invoice. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "document_id": "d_9c31be",
  "number": "RE1031",
  "reminder_number": 1,
  "fee_amount": 5,
  "sent_to": "buchhaltung@nordlicht.example",
  "sent_at": "2026-10-14T08:02:00+02:00"
}
```

### cancel_invoice

Cancel (stornieren) a finalised invoice. The number stays blocked. Access: write, asks the user first. REST: `POST /api/v1/lexware-office/documents/{document_id}/invoice/cancel`. MCP: `lexware_office_write → cancel_invoice`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `document_id` | string | yes | Document ID from list_documents or create_invoice. |

Opens Weitere Aktionen > Stornieren on an open invoice. The original shows a Storno stamp and its booking is reversed, and the cancellation cannot be undone; the cancelled number stays blocked even if you change the number range. A paid invoice needs its payment deleted first, and the restricted role "Belege, Kontakte & Produkte" cannot cancel paid invoices. Use create_invoice for the corrected one. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "document_id": "d_9c31be",
  "number": "RE1031",
  "status": "voided"
}
```

### upload_receipt

Upload a supplier invoice or receipt file for bookkeeping. It lands in "Zu prüfen". Access: write. REST: `POST /api/v1/lexware-office/receipts`. MCP: `lexware_office_write → upload_receipt`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `file_name` | string | yes | File name with extension, e.g. invoice.pdf. |
| `file_url` | string | yes | HTTPS URL of the PDF or image to upload. |

Uploads one file as a receipt. Lexware Office runs its automatic recognition and saves it with the status Zu prüfen; it is not booked until someone clicks Beleg erfassen. It reaches no one and can be deleted in the app, so it does not ask for your OK. Returns the fields the recognition filled in.

Example response:

```json
{
  "receipt_id": "r_21b8c0",
  "file_name": "Hetzner-2026-10.pdf",
  "status": "to_check",
  "contact": "Hetzner Online GmbH",
  "receipt_number": "R0023981",
  "date": "2026-10-01",
  "amount_gross": 24.99,
  "currency": "EUR"
}
```

## How do I connect Lexware Office (lexoffice) to Claude Code, Codex or Cursor?

Connecting Lexware Office (lexoffice) takes three steps: sign up, sign in to Lexware Office (lexoffice) once in your Cloud Browser and enable it for agents, then add one MCP server or call the REST API with the same key.

### Connect Lexware Office (lexoffice) to your agent.

1. **Create an account** Sign up and add Lexware Office (lexoffice) in the console. Your API key is there too.

2. **Sign in to Lexware Office (lexoffice) in your Cloud Browser** Open your Cloud Browser in the console: your own Chrome in the cloud. Sign in to Lexware Office (lexoffice) there yourself, the way you always do, then press Enable for agents, read only or read and write. We never save your password, and your agent keeps working even when your computer is off.

3. **Add Cotlet to your agent** Paste the snippet for your client. The same server and key serve every app you connect, so you do this once.

   Claude Code:

```
claude mcp add --transport http cotlet \
  https://cotlet.dev/mcp/v1 \
  --header "Authorization: Bearer $COTLET_API_KEY"
```

   Cursor:

```
{
  "mcpServers": {
    "cotlet": {
      "url": "https://cotlet.dev/mcp/v1",
      "headers": {
        "Authorization": "Bearer ${COTLET_API_KEY}"
      }
    }
  }
}
```

   Codex:

```
# ~/.codex/config.toml
[mcp_servers.cotlet]
url = "https://cotlet.dev/mcp/v1"
bearer_token_env_var = "COTLET_API_KEY"
```

4. **Ask your agent** Ask in plain words. Your agent finds the Lexware Office (lexoffice) tools on the server and calls them for you; anything that reaches other people waits for your OK unless you switch that off for a tool.

```
Here is this month's billing list. For each customer, create the invoice in Lexware Office with the hours and rate I gave, check the totals against the list, finalise it and send it by email. Add customers that do not exist yet.
```

### Call Lexware Office (lexoffice) from your scripts.

1. **Export your API key** Your scripts use the same API key as your agent. Keep it in an environment variable, never in your code.

```
export COTLET_API_KEY="cotlet_..."
```

2. **Call a tool** Every tool is an endpoint under /api/v1/lexware-office with its own method and path, listed with the endpoints above. Path parameters go in the URL; the other parameters go in the query for GET and DELETE and in a JSON body otherwise.

```
curl -X POST https://cotlet.dev/api/v1/lexware-office/documents/d_c44e19/finalize \
  -H "Authorization: Bearer $COTLET_API_KEY"
```

3. **Read the result** You get plain JSON back, ready for your script. A failed call costs nothing.

```
{
  "document_id": "d_c44e19",
  "type": "invoice",
  "number": "RE1043",
  "status": "open",
  "total_gross": 1130.5,
  "currency": "EUR"
}
```

## Why use Cotlet for Lexware Office (lexoffice)?

**Built for agents**

- One MCP server for every app you connect.
- The same tools as a REST API for scripts and cron jobs.
- Works with Claude Code, Codex and Cursor.

**Your login stays yours**

- You sign in to Lexware Office (lexoffice) yourself, in your own Cloud Browser. We never save your password; the profile is encrypted with AES-256-GCM, the cipher 1Password uses.
- A+ on Qualys SSL Labs, securityheaders.com and Mozilla Observatory.
- The model never sees a login.
- No stored passwords, no CAPTCHA solving, no MFA bypass.

**You stay in control**

- Scope each API key: its apps, its tools, read only or read and write.
- Anything that reaches other people waits for your OK, so a leaked key cannot post or message as you.
- Every background request listed in your Background activity. Disable for agents in one click.

**Kept working for you**

- We test every integration every 6 hours.
- When Lexware Office (lexoffice) changes, the tool pauses until we fix it.
- Failed calls cost nothing.

## Is it safe to connect Lexware Office (lexoffice) to Cotlet?

Yes. You sign in to Lexware Office (lexoffice) yourself, in your own Cloud Browser, and we never save your password. Your agents only get Lexware Office (lexoffice) once you enable it, and every background request is listed. The browser profile is stored encrypted with AES-256-GCM, the same cipher 1Password uses for its vaults and Apple for iCloud Keychain. Independent public scanners grade cotlet.dev A+ and find it clean; click a result to rerun it yourself.

- **A+ on Qualys SSL Labs**: Encryption in transit: TLS setup and certificates, on all four server addresses. [Live result](https://www.ssllabs.com/ssltest/analyze.html?d=cotlet.dev)
- **A+ on securityheaders.com**: Browser protections sent with every page, all six headers present. [Live result](https://securityheaders.com/?q=cotlet.dev&followRedirects=on)
- **A+ on Mozilla Observatory**: Mozilla's web security baseline: score 120 of 100, 12 of 12 tests passed. [Live result](https://developer.mozilla.org/en-US/observatory/analyze?host=cotlet.dev)
- **Clean on Sucuri SiteCheck**: No malware, spam or defacement, and not on any of 9 blocklists, Google Safe Browsing included. [Live result](https://sitecheck.sucuri.net/results/cotlet.dev)

[How Cotlet protects your access](https://cotlet.dev/security.md)

### Common concerns

**Who runs Cotlet?**

Cotlet is run by Take Group, a Polish software company working since 2019. Take Group runs about 3,200 websites on its own systems and has its own DevOps team for infrastructure security. We built and used integrations like this inside the company for years before opening them as Cotlet.

**Is this an official Lexware Office (lexoffice) integration?**

No, Cotlet is independent of Lexware Office (lexoffice). Lexware Office (lexoffice)'s own API comes only with a paid plan. Cotlet works through your own Lexware Office (lexoffice) account, the way you use Lexware Office (lexoffice) in the browser, so you need no partner approval and no developer setup.

**What about client data and GDPR?**

Cotlet is run from the EU and follows the GDPR. Cloud Browsers run in Finland, a Tier 1 country in the ITU Global Cybersecurity Index 2024. Data passes through a call and is not kept after it.

**Can I start with read only?**

Yes. Enable the app for agents as read only, or make the API key read only, and anything that reaches other people waits for your OK unless you switch that off per tool.

**Is it reliable?**

Every Cotlet service is checked every 3 minutes from Europe, North America, Asia and Australia. The live results and any outage are public at status.cotlet.dev.

**How do I stop?**

Press Disable for agents next to Lexware Office (lexoffice) in your console: your agents lose access at once and you stay signed in. Signing out of Lexware Office (lexoffice) in the browser works too, and Reset browser deletes the whole profile.

## Is there a Lexware Office (lexoffice) MCP server on GitHub?

Yes. Community Lexware Office MCP servers exist on GitHub, usually maintained by one person. You install one on your own computer, give it an API key from a version XL account, and keep it running yourself; when Lexware changes its API, it stops working until you or the maintainer fix it. The official API is the other route: upgrade to version XL, generate a key and write the calls yourself. Cotlet hosts the same kind of server for you, signs in to your Lexware Office account in a browser, and our team keeps it working.

|  | GitHub MCP server | Cotlet |
|---|---|---|
| Setup | Upgrade to version XL, generate an API key, install the server, add it to each MCP client | Sign up, sign in to Lexware Office once, add one MCP server or API key |
| Plan needed | Version XL, because the API key is only available there | Your own Lexware Office version, as long as it includes the screen the tool uses |
| When Lexware changes | It breaks until you or the maintainer fix it | Our team tests it daily and fixes it for you; failed calls are free |
| Your Lexware access | An API key in a file on your computer, with full access to the company | Signed in inside your own Cloud Browser in the EU, profile encrypted, only for the apps you enable, disabled for agents in one click |
| Send, cancel, remind | The API has no endpoint for sending by email, cancelling an invoice, recording a payment or reminders | The same buttons you click in the app: send, cancel, record a payment, remind |
| Upkeep | You update, monitor and debug it yourself | Nothing to host or update |
| Where it runs | Your computer, while it is on | Hosted: Claude Code, Codex, Cursor, n8n and scripts, also on a schedule |
| Price | Free, paid for with your time and the version XL fee | Free 7-day trial, then pay-as-you-go credit packs, no subscription |

### Which one fits you

**Pick Cotlet if**

- you are not a developer, or you do not want to maintain a server
- you need it to keep working when Lexware Office (lexoffice) changes, without checking it yourself
- your agent or a script should run it on a schedule, also while your computer is off

**Pick an open-source server if**

- you are comfortable installing, updating and fixing it yourself
- you want your sign-in to stay on your own computer
- you only need it now and then, from one MCP client

## How much does the Lexware Office (lexoffice) API cost?

Free 7-day trial with 2,000 credits, no card needed. After that, the Lexware Office (lexoffice) API is pay as you go with no limit on apps: Credit packs from $29 for 5,000 credits, one-time, no subscription. A successful call uses 20 to 30 credits (25 for most tools, about $0.10 to $0.15), your Cloud Browser uses 50 credits a day while it has an app enabled for agents, however many apps that is, and an agent driving the browser itself uses 5 credits a minute. Credit packs stay valid for 12 months and stack, so unused credits carry over.

| Credits | Price, one time | Calls at 25 credits | Per 1,000 credits |
|---|---|---|---|
| 5,000 | $29 | 200 | $5.80 |
| 15,000 | $79 | 600 | $5.27 |
| 32,000 | $149 | 1,280 | $4.66 |
| 60,000 | $249 | 2,400 | $4.15 |

Only successful calls use credits; failed calls and timeouts cost nothing. At a balance of 0 calls pause, never a surprise charge. Authenticate with the `Authorization: Bearer` header. [See full pricing](https://cotlet.dev/pricing.md)

## How Cotlet holds your access

Cotlet hosts MCP servers and REST APIs for apps with no usable API. Your agent works in your own Lexware Office (lexoffice) account.

- **Company details:** Cotlet is run by Take Group sp. z o.o., a company registered in Poland. Its full address and registration numbers are in the Terms of service. [Terms of service](https://cotlet.dev/terms)
- **Your sign-in:** You sign in to Lexware Office (lexoffice) yourself, in your own Cloud Browser: a Chrome we run for you in the EU, one per app. We never save your password (password saving is off), the profile is stored encrypted with AES-256-GCM, and your agents get Lexware Office (lexoffice) only after you enable it. When Lexware Office (lexoffice) signs you out, your agent gives you a link to sign in again. [Security](https://cotlet.dev/security.md)
- **Revoking access:** Press Disable for agents next to Lexware Office (lexoffice), sign out of Lexware Office (lexoffice) in your Cloud Browser, or reset the browser. Every background request is listed in your Background activity. Actions that reach other people wait for your OK unless you switch that off per tool.
- **What we never do:** Store passwords, solve CAPTCHAs or bypass MFA.
- **Lexware Office (lexoffice)'s terms:** You use your own Lexware Office (lexoffice) account and stay responsible for following Lexware Office (lexoffice)'s terms. Cotlet is independent and not affiliated with Lexware Office (lexoffice). [Terms](https://cotlet.dev/terms)
- **Contact:** Questions about the company, security or an app: [contact@cotlet.dev](mailto:contact@cotlet.dev)

## Frequently asked questions

**How do I get access?**

Sign up free, open Lexware Office (lexoffice) in the console and press Request access. Then you create your API key and connect Lexware Office (lexoffice) there.

**Do I need to be technical?**

No. You sign in to Lexware Office (lexoffice) once in your Cloud Browser, a normal Chrome you open from the console, and paste one command into your agent, or one URL into n8n. Your agent can walk you through it. There is no server to install, update or fix.

**Is it safe to connect Lexware Office (lexoffice) to Cotlet?**

Yes. You sign in to Lexware Office (lexoffice) yourself, in your own Cloud Browser in the EU, and we never save your password. Your agents only get Lexware Office (lexoffice) once you enable it, every background request is listed, and the browser profile is stored encrypted with AES-256-GCM, the cipher 1Password uses for its vaults. The AI model never sees a login, posts and messages wait for your OK, and Disable for agents cuts access in one click. Independent scanners grade cotlet.dev A+ on Qualys SSL Labs, securityheaders.com and Mozilla Observatory; live results are on https://cotlet.dev/security.

**Is a hosted server safer than a local one? My Lexware Office (lexoffice) sign-in would leave my computer.**

On Cotlet you sign in inside your own Cloud Browser, which only you open, and its profile is stored encrypted with AES-256-GCM in the EU. Agents get only the apps you enable, and every background request is listed. A local server keeps your Lexware Office (lexoffice) cookie in a plain file on your computer, readable by any program you run, and stops when your computer is off.

**Why does Cotlet send requests instead of clicking in my browser?**

To be fast, Cotlet doesn't click through Lexware Office (lexoffice)'s pages. It sends the same requests your browser would, from your browser's IP with its cookies, without opening a window. Lexware Office (lexoffice) sees the same browser and IP you signed in with, and every request is listed in your Background activity.

**What if someone gets my Cotlet API key?**

The key holds no Lexware Office (lexoffice) login or cookies, it only asks Cotlet to run a tool. It can call only the apps and tools you gave it, and a read-only key changes nothing. Anything that reaches other people, like posts, comments or messages, waits for your OK in the dashboard by default, so a leaked key cannot post or message as you. When you switch approval off for a scheduled job, give that job its own key limited to that one tool. Every call is in your activity log, and deleting the key ends access at once.

**Why a signed-in browser and not OAuth, like other integration platforms?**

Lexware Office (lexoffice) offers no OAuth token you can simply grant for these tools: its official API leaves them out or needs a developer app, a plan or an approval first (see the official API section above). That is why Cotlet sets the limits itself: per key, per tool, with your approval before anything reaches other people. Cotlet is run by Take Group sp. z o.o., an EU company (VAT PL6342984273).

**Do I need Lexware Office version XL to use Cotlet?**

No. The public API needs version XL (checked 14 Oct 2026), but Cotlet works the screens you use yourself. Invoices, quotes and reminders need version M or higher, and receipt capture is part of version S.

**Can my agent undo a finalised invoice?**

Only the way you would: cancel_invoice clicks Stornieren, and the corrected invoice is a new document. A cancellation cannot be undone and the cancelled number stays blocked, which Lexware says GoBD requires.

**Can my agent post or send messages in Lexware Office (lexoffice) without asking me?**

No. Every call to finalize_document, send_document, record_payment, send_payment_reminder or cancel_invoice waits for your OK by default. For scheduled automations you can switch confirmation off per tool in your dashboard, for example only for approvals. create_contact, create_invoice, create_quotation, upload_receipt runs without asking, because it sends nothing to anyone and one call undoes it.

**Can I use the Lexware Office (lexoffice) API in n8n?**

Yes. Add https://cotlet.dev/mcp/v1 with your API key in n8n's MCP Client node, or call its endpoints under https://cotlet.dev/api/v1/lexware-office from the HTTP Request node.

---

Give your AI agents your signed-in browser.

**Product:** [Integrations](https://cotlet.dev/integrations.md) · [Use cases](https://cotlet.dev/use-cases.md) · [How it works](https://cotlet.dev/how-it-works.md) · [Pricing](https://cotlet.dev/pricing.md) · [Security](https://cotlet.dev/security.md)

**Resources:** [Blog](https://cotlet.dev/blog.md) · [API docs](https://cotlet.dev/docs.md) · [Help center](https://cotlet.dev/help.md) · [Changelog](https://cotlet.dev/changelog.md) · [GitHub](https://github.com/cotletdev/cotlet)

**Solutions:** [For developers](https://cotlet.dev/for-developers.md) · [For automation agencies](https://cotlet.dev/for-agencies.md)

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**Elsewhere:** [Status page](https://status.cotlet.dev) · [Cotlet on GitHub](https://github.com/cotletdev) · [Cotlet on X](https://x.com/cotletdev) · [Cotlet on LinkedIn](https://www.linkedin.com/company/cotletdev) · [Cotlet on Product Hunt](https://www.producthunt.com/products/cotlet) · [Cotlet on Crunchbase](https://www.crunchbase.com/organization/cotlet) · [Cotlet on SaaSHub](https://www.saashub.com/cotlet)

Cotlet is an independent service. It is not affiliated with, endorsed by or sponsored by any of the products listed on this site. Product names are trademarks of their respective owners.

## For AI agents: sign your user up

Is your user asking you to sign them up for Cotlet? You can do it for them, no account or key needed.

1. Read the fields and their allowed values: GET https://cotlet.dev/api/v1/access-requests
2. Ask the user for each value: email, apps, what you will do with them. If they leave the password to you, generate a strong one and show it to them.
3. Show the user what you will send, then POST it as JSON to https://cotlet.dev/api/v1/access-requests.

One call creates the account and sends the access request; we email the user when access is granted.