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# sevdesk API and MCP server

> sevdesk has a REST API (checked 14 Oct 2026). It covers almost everything the web app does, but only on the Buchhaltung Pro plan, in Germany, on system version 2.0. Each administrator has one API token, and sevdesk publishes no MCP server.

German online accounting software for freelancers and small businesses: invoices and e-invoices, quotes, receipts (Belege), contacts, bank accounts and tax reports in one web app.

## What is the sevdesk API?

Cotlet's sevdesk API exposes 14 endpoints for your own sevdesk account: list invoices, get invoice, list contacts, list receipts, list payment accounts, list bank transactions, create contact, create invoice draft, send invoice, create payment reminder, mark invoice as paid, cancel invoice, upload receipt and mark receipt as paid. The list_invoices endpoint returns invoices with number, customer, status, dates and total, newest first. Each endpoint takes simple JSON inputs like invoice_id, limit or cursor and works both as an operation of the sevdesk_read or sevdesk_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 (6 read, 8 write)
- **Updated:** 2026-10-20

sevdesk has a REST API (checked 14 Oct 2026). Cotlet is a hosted MCP server and REST API for sevdesk with 14 endpoints (6 read, 8 write): you sign in once in your own cloud browser, your AI agent does the work.

## Does sevdesk have an official API?

sevdesk has a REST API (checked 14 Oct 2026). It covers almost everything the web app does, but only on the Buchhaltung Pro plan, in Germany, on system version 2.0. Each administrator has one API token, and sevdesk publishes no MCP server.

| Task | sevdesk official | Cotlet |
|---|---|---|
| List invoices and open items | Yes: GET /Invoice filters by status, date, number and contact | Yes |
| Create an invoice draft | Yes: Invoice/Factory/saveInvoice; new invoices start as drafts | Yes |
| Send an invoice by email, PDF or e-invoice XML | Yes: sendViaEmail marks the invoice as sent; sendXml attaches the e-invoice XML | Yes |
| Create a payment reminder | Partly: createInvoiceReminder creates the reminder from an invoice | Yes |
| Mark an invoice as paid | Yes: bookAmount, needs the ID of a payment account | Yes |
| Cancel an invoice | Yes: cancelInvoice creates the cancellation invoice | Yes |
| Upload a receipt as a draft | Yes: uploadTempFile, then saveVoucher with status draft | Yes |
| Mark a receipt as paid | Yes: Voucher bookAmount, same booking data as invoices | Yes |

Sources: [sevdesk Help: sevdesk API](https://hilfe.sevdesk.de/de/articles/9374668-sevdesk-api), [sevdesk API documentation (OpenAPI)](https://api.sevdesk.de/), [sevdesk Help: Where do I find my API token](https://hilfe.sevdesk.de/de/articles/9374740-wo-finde-ich-meinen-api-token-in-sevdesk), [sevdesk pricing: plans and features](https://sevdesk.de/preise/)

## For AI agents

```text
sevdesk has a REST API (checked 14 Oct 2026). It covers almost everything the web app does, but only on the Buchhaltung Pro plan, in Germany, on system version 2.0. Each administrator has one API token, and sevdesk publishes no MCP server.
Cotlet provides a hosted MCP server and REST API for sevdesk: 14 tools (6 read, 8 write).
Access       Sign up at https://cotlet.dev/app/signup?app=sevdesk, then request the app and create API keys in the Cotlet console.

MCP server   https://cotlet.dev/mcp/v1
MCP tools    sevdesk_read, sevdesk_write, reads and writes apart; call one with {"operation": "<operation>", "arguments": {...}}
REST base    https://cotlet.dev/api/v1/sevdesk, each operation at its own route, e.g. POST /api/v1/sevdesk/contacts/{contact_id}/invoice-drafts
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_invoices, get_invoice, list_contacts, list_vouchers, list_payment_accounts, list_bank_transactions, create_contact, create_invoice_draft, send_invoice, create_payment_reminder, mark_invoice_paid, cancel_invoice, upload_receipt, mark_voucher_paid
Confirm      send_invoice, create_payment_reminder, mark_invoice_paid, cancel_invoice, mark_voucher_paid (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/sevdesk-api-mcp-server.md

How access works:
1. The user signs up at https://cotlet.dev/app/signup?app=sevdesk, requests sevdesk in the Cotlet console and creates an API key there.
2. The user signs in to sevdesk once in their Cotlet Cloud Browser (their own Chrome in the cloud, opened from the console) and enables sevdesk 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 sevdesk 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 sevdesk 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 sevdesk 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 sevdesk 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 sevdesk 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 sevdesk's terms; Cotlet is not affiliated with sevdesk.
```

## What can an AI agent do in sevdesk?

Cotlet is best for German freelancers and small businesses on sevdesk who want their AI agent to chase overdue invoices, create and send invoices and file receipts without running or fixing a server.

- **[Chase overdue invoices](https://cotlet.dev/integrations/sevdesk-api-mcp-server/chase-overdue-invoices.md)** (runs: weekly): "Every Monday, list my sevdesk invoices that are overdue. For each one with no reminder yet, send a friendly payment reminder. Skip customers I tagged as VIP in the contact description and list them for me." → `list_invoices`, `get_invoice`, `create_payment_reminder`
- **[Create and send an invoice from a brief](https://cotlet.dev/integrations/sevdesk-api-mcp-server/create-and-send-invoices.md)**: "Create an invoice for Nordlicht Studio: website relaunch phase 2 for 1,200 EUR and 3 workshop days at 150 EUR, 19% VAT. Show me the draft, and when I say go, send it as an e-invoice." → `list_contacts`, `create_contact`, `create_invoice_draft`, `get_invoice`, `send_invoice`
- **[Digitize receipts and mark them paid](https://cotlet.dev/integrations/sevdesk-api-mcp-server/digitize-receipts.md)** (runs: daily): "Upload the new supplier receipts from my receipts folder to sevdesk as expenses. Then, for each receipt from last month that matches a bank transaction on my business account, mark it as paid." → `upload_receipt`, `list_vouchers`, `list_payment_accounts`, `list_bank_transactions`, `mark_voucher_paid`
- **Record payments as paid** (runs: daily): "Check which of my open sevdesk invoices were paid by PayPal or cash according to this list, and mark exactly those as paid on the right account with the payment date." → `list_invoices`, `list_payment_accounts`, `mark_invoice_paid`
- **Weekly open invoices report** (runs: weekly): "Every Monday, give me my open and overdue sevdesk invoices by customer, with totals, and highlight what turned overdue last week." → `list_invoices`, `list_contacts`
- **Cancel a wrong invoice**: "Invoice RE-1040 went to the wrong customer. Check that it is still unpaid, and if so cancel it and create a corrected draft for Brandt GmbH." → `get_invoice`, `cancel_invoice`, `create_invoice_draft`

## Can sevdesk automations run on a schedule in n8n, Make or Zapier?

Yes. Cotlet does not replace your automation platform: it gives it a sevdesk 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, 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/sevdesk/invoices. | 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/sevdesk/invoices 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 sevdesk.

### list_invoices

Invoices with number, customer, status, dates and total, newest first. Access: read. REST: `GET /api/v1/sevdesk/invoices`. MCP: `sevdesk_read → list_invoices`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `status` | enum | no | draft, open, due, paid or cancelled. Default: all. |
| `contact_id` | string | no | Only invoices of this customer, from list_contacts. |
| `invoice_number` | string | no | Exact invoice number, e.g. RE-1031. |
| `from_date` | date | no | Only invoices dated on or after this date. |
| `to_date` | date | no | Only invoices dated on or before this date. |
| `limit` | integer | no | 1 to 100. Default: 50. |
| `cursor` | string | no | Next page cursor from the previous call. |

Lists invoices newest first, with the customer, status, invoice date, due date and gross total. Status draft, open, due, paid or cancelled matches the tabs of the Rechnungen overview; due is the Fällig tab and cancelled the Storno tab. Filter by customer, invoice number or date range. Pages hold up to 100 invoices; pass next_cursor back as cursor for the next page.

Example response:

```json
{
  "invoices": [
    {
      "invoice_id": "41872618",
      "invoice_number": "RE-1031",
      "contact": {
        "contact_id": "3084102",
        "name": "Brandt GmbH"
      },
      "status": "due",
      "invoice_date": "2026-09-14",
      "due_date": "2026-09-28",
      "total_gross": 226.1,
      "currency": "EUR"
    }
  ],
  "next_cursor": null
}
```

### get_invoice

One invoice with its positions, totals, status, e-invoice setting and linked reminders. Access: read. REST: `GET /api/v1/sevdesk/invoices/{invoice_id}`. MCP: `sevdesk_read → get_invoice`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `invoice_id` | string | yes | Invoice ID from list_invoices. |

Returns one invoice as the invoice mask shows it: customer, positions with quantity, unit, net price and tax rate, totals, status and whether the E-Rechnung toggle is on. Linked payment reminders are listed oldest first, so your agent can see whether a customer was already chased. The totals are the numbers sevdesk calculated.

Example response:

```json
{
  "invoice_id": "41872618",
  "invoice_number": "RE-1031",
  "contact": {
    "contact_id": "3084102",
    "name": "Brandt GmbH",
    "email": "billing@brandt-gmbh.example"
  },
  "status": "due",
  "invoice_date": "2026-09-14",
  "due_date": "2026-09-28",
  "e_invoice": false,
  "positions": [
    {
      "name": "Consulting hour",
      "quantity": 2,
      "unit": "hour",
      "unit_price_net": 95,
      "tax_rate": 19,
      "total_net": 190
    }
  ],
  "total_net": 190,
  "total_tax": 36.1,
  "total_gross": 226.1,
  "currency": "EUR",
  "reminders": []
}
```

### list_contacts

Customers, suppliers and other contacts with category and email, matched by name. Access: read. REST: `GET /api/v1/sevdesk/contacts`. MCP: `sevdesk_read → list_contacts`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `search` | string | no | Part of the name. |
| `category` | string | no | Category name, e.g. Kunde or Lieferant. |
| `customer_number` | string | no | Exact customer number. |
| `limit` | integer | no | 1 to 100. Default: 50. |
| `cursor` | string | no | Next page cursor from the previous call. |

Searches contacts by name and returns persons and organizations with their category (Kunde, Lieferant, Partner, Interessent or one you created), email and customer number. Pass contact_id to create_invoice_draft or list_invoices. Pages hold up to 100 contacts; pass next_cursor back as cursor for the next page.

Example response:

```json
{
  "contacts": [
    {
      "contact_id": "3084417",
      "kind": "organization",
      "name": "Nordlicht Studio",
      "category": "Kunde",
      "customer_number": "1017",
      "email": "accounts@nordlicht-studio.example"
    }
  ],
  "next_cursor": null
}
```

### list_vouchers

Receipts (Belege) for expenses and income with supplier, amount and status, newest first. Access: read. REST: `GET /api/v1/sevdesk/vouchers`. MCP: `sevdesk_read → list_vouchers`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `status` | enum | no | draft, unpaid or paid. Default: all. |
| `kind` | enum | no | expense or income. Default: both. |
| `from_date` | date | no | Only receipts dated on or after this date. |
| `to_date` | date | no | Only receipts dated on or before this date. |
| `search` | string | no | Text in the receipt description. |
| `limit` | integer | no | 1 to 100. Default: 50. |
| `cursor` | string | no | Next page cursor from the previous call. |

Lists the receipts of the Belege area newest first, with supplier, receipt date, gross amount and status. Status draft is an upload that still needs checking, unpaid waits for a payment and paid is booked. Filter by type, status, date range or text in the description. Pages hold up to 100 receipts.

Example response:

```json
{
  "vouchers": [
    {
      "voucher_id": "77120344",
      "kind": "expense",
      "supplier": "Nordhost Cloud GmbH",
      "receipt_number": "NH-2026-0912",
      "receipt_date": "2026-09-12",
      "total_gross": 39,
      "currency": "EUR",
      "status": "unpaid"
    }
  ],
  "next_cursor": null
}
```

### list_payment_accounts

Your payment accounts (Zahlungskonten) with type and which one is the default. Access: read. REST: `GET /api/v1/sevdesk/payment-accounts`. MCP: `sevdesk_read → list_payment_accounts`.

No parameters.

Lists the accounts of Einstellungen > Buchhaltung > Zahlungskonten. Type online is a connected bank account, import is a bank account filled from a CSV file and clearing is a Verrechnungskonto, an accounting helper account with no real bank behind it. default is the account sevdesk shows first when you book a payment.

Example response:

```json
{
  "payment_accounts": [
    {
      "payment_account_id": "5120031",
      "name": "Business account",
      "type": "online",
      "is_default": true
    },
    {
      "payment_account_id": "5120032",
      "name": "PayPal",
      "type": "import",
      "is_default": false
    },
    {
      "payment_account_id": "5120033",
      "name": "Verrechnungskonto",
      "type": "clearing",
      "is_default": false
    }
  ]
}
```

### list_bank_transactions

Transactions of one payment account with date, amount, counterparty and booked status. Access: read. REST: `GET /api/v1/sevdesk/payment-accounts/{payment_account_id}/bank-transactions`. MCP: `sevdesk_read → list_bank_transactions`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `payment_account_id` | string | yes | Payment account ID from list_payment_accounts. |
| `unbooked_only` | boolean | no | Only transactions not booked yet. Default: false. |
| `from_date` | date | no | Only transactions on or after this date. |
| `to_date` | date | no | Only transactions on or before this date. |
| `limit` | integer | no | 1 to 100. Default: 50. |
| `cursor` | string | no | Next page cursor from the previous call. |

Returns the transactions of one payment account, newest first, with amount, payer or payee, purpose text and whether the transaction is booked (gebucht) already. Set unbooked_only to see the ones that still need a receipt or invoice. Amounts are signed: money in is positive, money out is negative.

Example response:

```json
{
  "transactions": [
    {
      "transaction_id": "90311207",
      "date": "2026-09-15",
      "amount": -39,
      "currency": "EUR",
      "counterparty": "Nordhost Cloud GmbH",
      "purpose": "NH-2026-0912 Hosting September",
      "booked": false
    }
  ],
  "next_cursor": null
}
```

### create_contact

Add a customer, supplier or other contact, as a person or an organization. Access: write. REST: `POST /api/v1/sevdesk/contacts`. MCP: `sevdesk_write → create_contact`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `kind` | enum | yes | organization or person. |
| `name` | string | no | Organization name. Required for kind organization. |
| `first_name` | string | no | First name. For kind person. |
| `last_name` | string | no | Last name. Required for kind person. |
| `category` | string | no | Category name, e.g. Kunde or Lieferant. Default: Kunde. |
| `email` | string | no | Email address; needed later to send invoices and e-invoices. |
| `street` | string | no | Street and house number. |
| `zip` | string | no | Postal code. |
| `city` | string | no | City. |
| `country` | string | no | Country name or ISO code. Default: Germany. |

Creates a contact like the Kontakt erstellen button does. sevdesk knows persons and organizations; set kind and give name for an organization or first_name and last_name for a person. The category is Kunde, Lieferant, Partner, Interessent or one you created. create_contact sends nothing to anyone and runs without asking first: a new contact only appears in your own Kontakte list.

Example response:

```json
{
  "contact_id": "3084417",
  "kind": "organization",
  "name": "Nordlicht Studio",
  "category": "Kunde",
  "customer_number": "1017"
}
```

### create_invoice_draft

Create an invoice as a draft with its positions. Nothing is sent and the invoice number is not final. Access: write. REST: `POST /api/v1/sevdesk/contacts/{contact_id}/invoice-drafts`. MCP: `sevdesk_write → create_invoice_draft`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `contact_id` | string | yes | Customer ID from list_contacts or create_contact. |
| `positions` | array | yes | Lines of {name, quantity, unit, unit_price, tax_rate, description}. unit_price is net or gross as set by price_mode. |
| `price_mode` | enum | no | net or gross (Netto or Brutto). Default: net. |
| `invoice_date` | date | no | Invoice date. Default: today. |
| `subject` | string | no | Subject line of the invoice. |
| `e_invoice` | boolean | no | Switch on the E-Rechnung toggle. The contact needs an email address and your VAT ID must be set in sevdesk. Default: false. |
| `customer_reference` | string | no | Kundenreferenz or Leitweg-ID, for public clients. |

Creates a draft invoice for a contact with one or more positions, like the invoice mask before you finish it. Positions are net or gross as you choose with price_mode. The draft is not sent and not booked, and its number is only provisional: sevdesk fixes it when the invoice is finished with send_invoice. create_invoice_draft runs without asking first because it reaches nobody; send_invoice is the step that does.

Example response:

```json
{
  "invoice_id": "41873190",
  "invoice_number": "RE-1043",
  "number_final": false,
  "status": "draft",
  "contact": {
    "contact_id": "3084417",
    "name": "Nordlicht Studio"
  },
  "invoice_date": "2026-10-14",
  "e_invoice": true,
  "positions": 2,
  "total_net": 1650,
  "total_tax": 313.5,
  "total_gross": 1963.5,
  "currency": "EUR"
}
```

### send_invoice

Finish a draft invoice and email it to the customer, as a PDF or an e-invoice. Access: write, asks the user first. REST: `POST /api/v1/sevdesk/invoices/{invoice_id}`. MCP: `sevdesk_write → send_invoice`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `invoice_id` | string | yes | Invoice ID from list_invoices. |
| `to_email` | string | no | Recipient. Default: the email address of the invoice contact. |
| `subject` | string | no | Email subject. |
| `message` | string | no | Email text. |
| `format` | enum | no | zugferd_pdf or xrechnung_xml. Default: zugferd_pdf. |
| `copy_to_me` | boolean | no | Send a copy to your login email (Kopie an mich selbst). Default: false. |

Finishes the invoice and sends it by email, like Als E-Mail versenden. The invoice number is fixed from this moment and the status changes to open. Format zugferd_pdf sends the PDF with the XML inside (ZUGFeRD); xrechnung_xml sends only the XML (X-Rechnung). Sending is final: if sevdesk is set to enshrine on finishing, the invoice cannot be edited afterwards. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "invoice_id": "41873190",
  "invoice_number": "RE-1043",
  "status": "open",
  "sent_to": "accounts@nordlicht-studio.example",
  "format": "zugferd_pdf",
  "sent_at": "2026-10-14T10:42:00+02:00"
}
```

### create_payment_reminder

Create the next reminder for an overdue invoice and email it to the customer. Access: write, asks the user first. REST: `POST /api/v1/sevdesk/invoices/{invoice_id}/payment-reminders`. MCP: `sevdesk_write → create_payment_reminder`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `invoice_id` | string | yes | Invoice ID from list_invoices. |
| `message` | string | no | Text of the reminder. Default: the sevdesk standard text. |

Creates the next reminder for an invoice and sends it by email. The first one is a Zahlungserinnerung; later ones are Mahnungen, which sevdesk offers from the Buchhaltung plan and bases on an invoice that already got a reminder. The text is prefilled by sevdesk unless you pass message, and the deadline comes from your Mahnfrist setting. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "reminder_id": "88100412",
  "invoice_id": "41872618",
  "kind": "payment_reminder",
  "status": "sent",
  "sent_to": "billing@brandt-gmbh.example",
  "sent_at": "2026-10-14T09:10:00+02:00"
}
```

### mark_invoice_paid

Book a payment received on an invoice, on a payment account and date. Access: write, asks the user first. REST: `POST /api/v1/sevdesk/payment-accounts/{payment_account_id}/invoices/{invoice_id}/paid/mark`. MCP: `sevdesk_write → mark_invoice_paid`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `invoice_id` | string | yes | Invoice ID from list_invoices. |
| `payment_account_id` | string | yes | Payment account ID from list_payment_accounts. |
| `paid_on` | date | no | Payment date. Default: today. |
| `amount` | number | no | Amount received. Default: the open total of the invoice. |

Books a payment on an invoice, like Zahlungseingang buchen. The amount defaults to the open total; pass a smaller amount for a partial payment. All reminders linked to the invoice change to paid as well. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "invoice_id": "41872618",
  "invoice_number": "RE-1031",
  "status": "paid",
  "booked_amount": 226.1,
  "currency": "EUR",
  "paid_on": "2026-10-13",
  "payment_account": "PayPal"
}
```

### cancel_invoice

Cancel an unpaid invoice by creating a cancellation invoice (Stornorechnung). Access: write, asks the user first. REST: `POST /api/v1/sevdesk/invoices/{invoice_id}/cancel`. MCP: `sevdesk_write → cancel_invoice`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `invoice_id` | string | yes | Invoice ID from list_invoices. |

Cancels an invoice that is open or due, like Rechnung stornieren. sevdesk creates a cancellation invoice that refers to the original, sets it to paid and sets the original to cancelled. The cancellation invoice takes the next free number of your invoice number range. A paid invoice cannot be cancelled this way; it needs a credit note. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "invoice_id": "41872600",
  "invoice_number": "RE-1040",
  "status": "cancelled",
  "cancellation_invoice_id": "41873244",
  "cancellation_invoice_number": "RE-1044"
}
```

### upload_receipt

Upload a receipt file as a draft in Belege and return what the recognition found. Access: write. REST: `POST /api/v1/sevdesk/receipts`. MCP: `sevdesk_write → upload_receipt`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `file_url` | string | yes | Public or signed URL of a PDF, PNG or JPG file. |
| `kind` | enum | yes | expense (Ausgabe) or income (Einnahme). |

Uploads a PDF, PNG or JPG from a URL to Belege as a draft, the same as dragging the file into the overview. sevdesk then tries to fill date, amount, receipt number, supplier and category, and the response shows what it found. The upload stays a draft: nothing is booked and nobody is notified, so it runs without asking first. Check the category and tax rule in sevdesk before you finish it.

Example response:

```json
{
  "voucher_id": "77120418",
  "kind": "expense",
  "status": "draft",
  "recognized": {
    "supplier": "Nordhost Cloud GmbH",
    "receipt_number": "NH-2026-1012",
    "receipt_date": "2026-10-12",
    "total_gross": 39,
    "currency": "EUR",
    "category": null
  }
}
```

### mark_voucher_paid

Mark a receipt as paid, linked to a bank transaction or booked on a payment account. Access: write, asks the user first. REST: `POST /api/v1/sevdesk/payment-accounts/{payment_account_id}/vouchers/{voucher_id}/paid/mark`. MCP: `sevdesk_write → mark_voucher_paid`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `voucher_id` | string | yes | Receipt (Beleg) ID from list_vouchers or upload_receipt. |
| `payment_account_id` | string | yes | Payment account ID from list_payment_accounts. |
| `transaction_id` | string | no | Bank transaction from list_bank_transactions to link the receipt to. |
| `paid_on` | date | no | Payment date when there is no transaction. Default: today. |

Marks a receipt as paid like Als bezahlt markieren. With transaction_id the receipt is linked to that bank transaction, which becomes booked. Without it the payment is booked on the account with paid_on as the payment date, which suits a Verrechnungskonto. Only a receipt in status unpaid can be marked. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "voucher_id": "77120344",
  "status": "paid",
  "transaction_id": "90311207",
  "booked_amount": 39,
  "currency": "EUR",
  "payment_account": "Business account"
}
```

## How do I connect sevdesk to Claude Code, Codex or Cursor?

Connecting sevdesk takes three steps: sign up, sign in to sevdesk 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 sevdesk to your agent.

1. **Create an account** Sign up and add sevdesk in the console. Your API key is there too.

2. **Sign in to sevdesk in your Cloud Browser** Open your Cloud Browser in the console: your own Chrome in the cloud. Sign in to sevdesk 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 sevdesk 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.

```
Every Monday, list my sevdesk invoices that are overdue. For each one with no reminder yet, send a friendly payment reminder. Skip customers I tagged as VIP in the contact description and list them for me.
```

### Call sevdesk 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/sevdesk 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/sevdesk/contacts/3084417/invoice-drafts \
  -H "Authorization: Bearer $COTLET_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"positions":[{"name":"Website relaunch, phase 2","quantity":1,"unit":"piece","unit_price":1200,"tax_rate":19},{"name":"Workshop day","quantity":3,"unit":"day","unit_price":150,"tax_rate":19}],"price_mode":"net","subject":"Invoice website relaunch phase 2","e_invoice":true}'
```

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

```
{
  "invoice_id": "41873190",
  "invoice_number": "RE-1043",
  "number_final": false,
  "status": "draft",
  "contact": {
    "contact_id": "3084417",
    "name": "Nordlicht Studio"
  },
  "invoice_date": "2026-10-14",
  "e_invoice": true,
  "positions": 2,
  "total_net": 1650,
  "total_tax": 313.5,
  "total_gross": 1963.5,
  "currency": "EUR"
}
```

## Why use Cotlet for sevdesk?

**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 sevdesk 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 sevdesk changes, the tool pauses until we fix it.
- Failed calls cost nothing.

## Is it safe to connect sevdesk to Cotlet?

Yes. You sign in to sevdesk yourself, in your own Cloud Browser, and we never save your password. Your agents only get sevdesk 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 sevdesk integration?**

No, Cotlet is independent of sevdesk. sevdesk's own API comes only with a paid plan. Cotlet works through your own sevdesk account, the way you use sevdesk 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 sevdesk in your console: your agents lose access at once and you stay signed in. Signing out of sevdesk in the browser works too, and Reset browser deletes the whole profile.

## Is there a sevdesk MCP server on GitHub?

Yes. Open-source sevdesk MCP servers exist on GitHub and npm, usually maintained by one person. They call the official API with your token, so you need the Buchhaltung Pro plan, install the server yourself and fix it when sevdesk changes the API. Cotlet hosts the same kind of server for you, and our team keeps it working.

|  | GitHub MCP server | Cotlet |
|---|---|---|
| Setup | Find the token in sevdesk, clone the repo, install it, add it to each MCP client | Sign up, sign in to sevdesk once, add one MCP server or API key |
| Plan | Needs the Buchhaltung Pro plan for the API | Works through your own web sign-in; what you can do follows your plan |
| When sevdesk changes | Calls fail until you or the maintainer fix them, as with the tax rule changes of system version 2.0 | Our team tests it daily and fixes it for you; failed calls are free |
| Your credentials | Your API token, which the docs describe without scopes, in a file on your computer | Signed in inside your own Cloud Browser in the EU, no password saved, profile encrypted, only for the apps you enable, disabled for agents in one click |
| When access ends | The token never expires; if it leaks you must generate a new one in sevdesk | Your Cloud Browser keeps you signed in; if sevdesk logs you out, your agent gets a link to sign in again |
| 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 | 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 sevdesk 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 sevdesk API cost?

Free 7-day trial with 2,000 credits, no card needed. After that, the sevdesk 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 sevdesk 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 sevdesk 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 sevdesk only after you enable it. When sevdesk 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 sevdesk, sign out of sevdesk 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.
- **sevdesk's terms:** You use your own sevdesk account and stay responsible for following sevdesk's terms. Cotlet is independent and not affiliated with sevdesk. [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 sevdesk in the console and press Request access. Then you create your API key and connect sevdesk there.

**Do I need to be technical?**

No. You sign in to sevdesk 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 sevdesk to Cotlet?**

Yes. You sign in to sevdesk yourself, in your own Cloud Browser in the EU, and we never save your password. Your agents only get sevdesk 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 sevdesk 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 sevdesk 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 sevdesk's pages. It sends the same requests your browser would, from your browser's IP with its cookies, without opening a window. sevdesk 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 sevdesk 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?**

sevdesk 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 the Buchhaltung Pro plan?**

Not for Cotlet. sevdesk gives API access only on Buchhaltung Pro (checked 14 Oct 2026), but Cotlet works in your own sevdesk web account, so it does what your plan allows in the web app. For example, Mahnungen after the first reminder need the Buchhaltung plan or higher.

**Can my agent send invoices without me checking them?**

It can, but by default it does not. create_invoice_draft makes a draft that reaches nobody, and send_invoice asks for your OK on each call. Switch confirmation off for send_invoice only when you trust the brief, because sevdesk fixes the invoice number when the invoice is sent.

**Can my agent post or send messages in sevdesk without asking me?**

No. Every call to send_invoice, create_payment_reminder, mark_invoice_paid, cancel_invoice or mark_voucher_paid 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_draft, upload_receipt runs without asking, because it sends nothing to anyone and one call undoes it.

**Can I use the sevdesk 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/sevdesk 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)

**Company:** [About](https://cotlet.dev/about.md) · [AI info: company facts](https://cotlet.dev/ai-info.md) · [Contact](https://cotlet.dev/contact.md)

**Legal:** [Terms of service](https://cotlet.dev/terms) · [Privacy policy](https://cotlet.dev/privacy) · [Refund policy](https://cotlet.dev/refunds) · [Acceptable use](https://cotlet.dev/acceptable-use) · [Cookie policy](https://cotlet.dev/cookies) · [DPA](https://cotlet.dev/dpa) · [Subprocessors](https://cotlet.dev/subprocessors)

**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.