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# e-Boekhouden API and MCP server

> Yes. e-Boekhouden has a REST API with an OpenAPI description (checked 14 Oct 2026). It covers relations, invoices, bookings (mutations), ledgers, products and outstanding invoices. It has no official MCP server, you create an API token in your account settings that is shown once, and you write the code that exchanges it for a short-lived session token.

Dutch online bookkeeping and invoicing software for freelancers, small businesses, associations and accountants: relations, invoices, bookings, ledgers and VAT returns in one package.

## What is the e-Boekhouden API?

Cotlet's e-Boekhouden API exposes 14 endpoints for your own e-Boekhouden account: list relations, get relation, list ledgers, get ledger balances, list products, list invoice templates, list invoices, get invoice, list mutations, list outstanding invoices, create relation, update relation, create invoice and create mutation. The list_relations endpoint returns customers and suppliers (relations) with code, name, city and email, filtered by name, email, code, city or type. Each endpoint takes simple JSON inputs like limit, offset or relation_id and works both as an operation of the e_boekhouden_read or e_boekhouden_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 (10 read, 4 write)
- **Updated:** 2026-10-16

Yes. Cotlet is a hosted MCP server and REST API for e-Boekhouden with 14 endpoints (10 read, 4 write): you sign in once in your own cloud browser, your AI agent does the work.

## Does e-Boekhouden have an official API?

Yes. e-Boekhouden has a REST API with an OpenAPI description (checked 14 Oct 2026). It covers relations, invoices, bookings (mutations), ledgers, products and outstanding invoices. It has no official MCP server, you create an API token in your account settings that is shown once, and you write the code that exchanges it for a short-lived session token.

| Task | e-Boekhouden official | Cotlet |
|---|---|---|
| Find relations (customers and suppliers) | Yes: GET /v1/relation filters by name, code, email, city and type | Yes |
| Add or update a relation | Yes: POST and PATCH /v1/relation | Yes |
| Create an invoice and email it | Yes: POST /v1/invoice; an email object sends it to the relation straight away | Yes |
| Search and read invoices | Yes: GET /v1/invoice by number, relation or date | Yes |
| Book a mutation (payment, journal entry, invoice received or sent) | Yes: POST /v1/mutation, seven mutation types | Yes |
| List open (outstanding) invoices | Yes: Debtors or creditors, GET /v1/mutation/invoice/outstanding | Yes |
| Read ledger balances | Yes: Balances per ledger, with optional date and cost center filters | Yes |
| Run all of this from an MCP client with one key | No: No official MCP server; the API needs your own session-token code | Yes |

Sources: [e-Boekhouden API reference (OpenAPI)](https://api.e-boekhouden.nl/openapi/v1.json), [e-Boekhouden: API-koppeling](https://www.e-boekhouden.nl/koppelingen/api), [e-Boekhouden: Prijzen (API listed among the features)](https://www.e-boekhouden.nl/prijzen)

## For AI agents

```text
Yes. e-Boekhouden has a REST API with an OpenAPI description (checked 14 Oct 2026). It covers relations, invoices, bookings (mutations), ledgers, products and outstanding invoices. It has no official MCP server, you create an API token in your account settings that is shown once, and you write the code that exchanges it for a short-lived session token.
Cotlet provides a hosted MCP server and REST API for e-Boekhouden: 14 tools (10 read, 4 write).
Access       Sign up at https://cotlet.dev/app/signup?app=e-boekhouden, then request the app and create API keys in the Cotlet console.

MCP server   https://cotlet.dev/mcp/v1
MCP tools    e_boekhouden_read, e_boekhouden_write, reads and writes apart; call one with {"operation": "<operation>", "arguments": {...}}
REST base    https://cotlet.dev/api/v1/e-boekhouden, each operation at its own route, e.g. POST /api/v1/e-boekhouden/relations/{relation_id}/invoices
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_relations, get_relation, list_ledgers, get_ledger_balances, list_products, list_invoice_templates, list_invoices, get_invoice, list_mutations, list_outstanding_invoices, create_relation, update_relation, create_invoice, create_mutation
Confirm      create_invoice, create_mutation (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/e-boekhouden-api-mcp-server.md

How access works:
1. The user signs up at https://cotlet.dev/app/signup?app=e-boekhouden, requests e-Boekhouden in the Cotlet console and creates an API key there.
2. The user signs in to e-Boekhouden once in their Cotlet Cloud Browser (their own Chrome in the cloud, opened from the console) and enables e-Boekhouden 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 e-Boekhouden server that someone else maintains, including non-developers.

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 e-Boekhouden 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 e-Boekhouden 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 e-Boekhouden 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 e-Boekhouden's terms; Cotlet is not affiliated with e-Boekhouden.
```

## What can an AI agent do in e-Boekhouden?

Cotlet is best for Dutch freelancers, small businesses and bookkeepers who want an AI agent to create invoices, book payments and report open items in e-Boekhouden without running or fixing a server.

- **[Create invoices from a list](https://cotlet.dev/integrations/e-boekhouden-api-mcp-server/create-invoices-from-a-list.md)**: "Create an October 2026 invoice for each client on this list with the hours and rate next to their name. Use my standard template, 14 days payment term, 21% VAT. Show me the totals before sending." → `list_relations`, `list_invoice_templates`, `create_invoice`
- **[Record invoice payments from a list](https://cotlet.dev/integrations/e-boekhouden-api-mcp-server/record-invoice-payments.md)** (runs: weekly): "For each payment in this payout report, find the open invoice with that number and book an Invoice payment received on my bank ledger. Skip any amount that does not match the open invoice." → `list_outstanding_invoices`, `list_ledgers`, `create_mutation`
- **Add new customers as relations**: "Add these five new clients to e-Boekhouden as business relations with their address, email and VAT number. Skip any that already exist by name or email." → `list_relations`, `create_relation`
- **Weekly open invoices report** (runs: weekly): "Every Monday, list my open debtor invoices, oldest first, with the relation and amount, and tell me the total." → `list_outstanding_invoices`, `get_relation`
- **Month-end ledger balances**: "Give me the balance of every ledger up to the last day of the month and flag any that changed more than 20% since last month." → `get_ledger_balances`, `list_ledgers`

## Can e-Boekhouden automations run on a schedule in n8n, Make or Zapier?

Yes. Cotlet does not replace your automation platform: it gives it a e-Boekhouden 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 record invoice payments from a list, 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/e-boekhouden/outstanding-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/e-boekhouden/outstanding-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 e-Boekhouden.

### list_relations

Customers and suppliers (relations) with code, name, city and email, filtered by name, email, code, city or type. Access: read. REST: `GET /api/v1/e-boekhouden/relations`. MCP: `e_boekhouden_read → list_relations`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `name` | string | no | Company or person name. Wildcards ? and % are allowed. |
| `email` | string | no | Exact email address. |
| `code` | string | no | Relation code. |
| `city` | string | no | Primary city. |
| `type` | enum | no | B (business) or P (private). |
| `limit` | integer | no | Number of items to return. |
| `offset` | integer | no | Number of items to skip, for the next page. |

Returns relations from the administration you are signed in to. Filter by name, email, relation code, city or type (B for business, P for private) to find one before you invoice it. Use limit and offset for the next page. The relation_id from each item goes into the other tools.

Example response:

```json
{
  "relations": [
    {
      "relation_id": 1042,
      "code": "STN001",
      "type": "B",
      "name": "Studio Noord BV",
      "city": "Utrecht",
      "email": "admin@studionoord.example",
      "term_of_payment": 14,
      "inactive": false
    }
  ],
  "total": 1
}
```

### get_relation

One relation with address, contacts, email addresses, VAT number, IBAN and payment term. Access: read. REST: `GET /api/v1/e-boekhouden/relations/{relation_id}`. MCP: `e_boekhouden_read → get_relation`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `relation_id` | integer | yes | Relation ID from list_relations. |

Returns the full record of one relation: primary and secondary address, phone, the invoice email address, VAT number, company registration number, IBAN, payment term and whether it is inactive. Use it before invoicing to see where the invoice will go.

Example response:

```json
{
  "relation_id": 1042,
  "code": "STN001",
  "type": "B",
  "name": "Studio Noord BV",
  "contact": "Eva de Boer",
  "address": "Voorbeeldstraat 12",
  "postal_code": "3511 AB",
  "city": "Utrecht",
  "country": "NL",
  "email": "admin@studionoord.example",
  "email_invoice": "facturen@studionoord.example",
  "vat_number": "NL000000000B01",
  "iban": "NL00BANK0123456789",
  "term_of_payment": 14,
  "inactive": false
}
```

### list_ledgers

Ledger accounts (grootboekrekeningen) with ID, code, name and category. Access: read. REST: `GET /api/v1/e-boekhouden/ledgers`. MCP: `e_boekhouden_read → list_ledgers`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `limit` | integer | no | Number of items to return. |
| `offset` | integer | no | Number of items to skip, for the next page. |

Returns the ledger accounts of the administration. The ledger_id goes into create_invoice lines and into create_mutation as the account the booking is made on. Look up the ID here instead of guessing a code.

Example response:

```json
{
  "ledgers": [
    {
      "ledger_id": 1155,
      "code": "1155",
      "name": "Payout account",
      "category": "Balance"
    },
    {
      "ledger_id": 8000,
      "code": "8000",
      "name": "Revenue consulting",
      "category": "Revenue"
    }
  ],
  "total": 2
}
```

### get_ledger_balances

The balance of every ledger, optionally from and up to a date and for one cost center. Access: read. REST: `GET /api/v1/e-boekhouden/ledger-balances`. MCP: `e_boekhouden_read → get_ledger_balances`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `from` | date | no | Start of the period, inclusive. |
| `to` | date | no | Balance on this date, inclusive. |
| `cost_center_id` | integer | no | Only bookings on this cost center. |

Returns one balance per ledger. With from set, the balance covers only that period; with to set, it is the balance on that date, inclusive. Add a cost center ID to narrow it. This is a balance per ledger, not a list of every booking.

Example response:

```json
{
  "balances": [
    {
      "ledger_id": 1155,
      "name": "Payout account",
      "balance": 4210
    },
    {
      "ledger_id": 8000,
      "name": "Revenue consulting",
      "balance": -18350
    }
  ],
  "to": "2026-10-31"
}
```

### list_products

Products and services with ID, code, description, price and VAT code. Access: read. REST: `GET /api/v1/e-boekhouden/products`. MCP: `e_boekhouden_read → list_products`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `limit` | integer | no | Number of items to return. |
| `offset` | integer | no | Number of items to skip, for the next page. |

Returns the product list so invoice lines can point to a product_id instead of retyping description and price. When a product ID is given on a line, the line code is ignored by e-Boekhouden.

Example response:

```json
{
  "products": [
    {
      "product_id": 17,
      "code": "CONS-H",
      "description": "Consulting hour",
      "price_per_unit": 85,
      "vat_code": "HOOG_VERK_21",
      "ledger_id": 8000
    }
  ],
  "total": 1
}
```

### list_invoice_templates

Invoice templates (layout and standard texts) with their IDs. Access: read. REST: `GET /api/v1/e-boekhouden/invoice-templates`. MCP: `e_boekhouden_read → list_invoice_templates`.

No parameters.

Returns the templates you made in e-Boekhouden. create_invoice needs one template_id, so call this first. Each item has an ID and a name.

Example response:

```json
{
  "templates": [
    {
      "template_id": 3,
      "name": "Standard invoice"
    },
    {
      "template_id": 5,
      "name": "Invoice with payment QR"
    }
  ]
}
```

### list_invoices

Invoices you created, searched by invoice number, relation or date. Access: read. REST: `GET /api/v1/e-boekhouden/invoices`. MCP: `e_boekhouden_read → list_invoices`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `invoice_number` | string | no | Only this invoice number. |
| `relation_id` | integer | no | Only invoices of this relation. |
| `date` | date | no | Only invoices on this date. |
| `limit` | integer | no | Number of items to return. |
| `offset` | integer | no | Number of items to skip, for the next page. |

Searches invoices in the administration. Filter by invoice number, relation_id or date, and page with limit and offset. Each item has the invoice number, date, relation and totals.

Example response:

```json
{
  "invoices": [
    {
      "invoice_id": 9021,
      "invoice_number": "2026-0143",
      "date": "2026-10-12",
      "relation_id": 1042,
      "total_excl_vat": 850,
      "vat": 178.5,
      "total_incl_vat": 1028.5
    }
  ],
  "total": 1
}
```

### get_invoice

One invoice with its lines, VAT per line and totals. Access: read. REST: `GET /api/v1/e-boekhouden/invoices/{invoice_id}`. MCP: `e_boekhouden_read → get_invoice`.

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

Returns the header and lines of one invoice: relation, date, payment term, reference, and for each line description, quantity, price, VAT code and ledger. Use it to check what an invoice contains before you book a payment on it.

Example response:

```json
{
  "invoice_id": 9021,
  "invoice_number": "2026-0143",
  "date": "2026-10-12",
  "relation_id": 1042,
  "term_of_payment": 14,
  "items": [
    {
      "description": "Consulting October 2026",
      "quantity": 10,
      "price_per_unit": 85,
      "vat_code": "HOOG_VERK_21",
      "ledger_id": 8000
    }
  ],
  "total_excl_vat": 850,
  "vat": 178.5,
  "total_incl_vat": 1028.5
}
```

### list_mutations

Bookings (mutations) filtered by type, date, invoice number or description. Access: read. REST: `GET /api/v1/e-boekhouden/mutations`. MCP: `e_boekhouden_read → list_mutations`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `type` | enum | no | 1 to 7, see details. |
| `date` | date | no | Only mutations on this date. |
| `invoice_number` | string | no | Only mutations with this invoice number. |
| `description` | string | no | Only mutations with this description. |
| `limit` | integer | no | Number of items to return. |
| `offset` | integer | no | Number of items to skip, for the next page. |

Returns mutations from the books. type is a number from 1 to 7: 1 invoice received, 2 invoice sent, 3 invoice payment received, 4 invoice payment sent, 5 money received, 6 money sent, 7 general journal entry. Use it to see whether a payment is already booked.

Example response:

```json
{
  "mutations": [
    {
      "mutation_id": 5513,
      "type": "3",
      "date": "2026-10-12",
      "ledger_id": 1155,
      "invoice_number": "2026-0143",
      "description": "Payout 12 Oct 2026",
      "amount": 1028.5
    }
  ],
  "total": 1
}
```

### list_outstanding_invoices

Open invoices of debtors (customers who owe you) or creditors (suppliers you owe), with the open amount. Access: read. REST: `GET /api/v1/e-boekhouden/outstanding-invoices`. MCP: `e_boekhouden_read → list_outstanding_invoices`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `cred_deb` | enum | no | D for debtors or C for creditors. |
| `invoice_number` | string | no | Only this invoice number. |
| `limit` | integer | no | Number of items to return. |
| `offset` | integer | no | Number of items to skip, for the next page. |

Returns invoices that are not fully paid. Choose debtors (D) or creditors (C), and narrow to one invoice number. Each item has the invoice number, relation and open amount. Use limit and offset to page through a long list.

Example response:

```json
{
  "invoices": [
    {
      "invoice_number": "2026-0151",
      "relation_id": 1068,
      "relation_name": "Bakkerij Smit",
      "invoice_date": "2026-09-28",
      "open_amount": 363
    },
    {
      "invoice_number": "2026-0143",
      "relation_id": 1042,
      "relation_name": "Studio Noord BV",
      "invoice_date": "2026-10-12",
      "open_amount": 1028.5
    }
  ],
  "total": 2
}
```

### create_relation

Add a customer or supplier with name, address, email, VAT number and IBAN. Access: write. REST: `POST /api/v1/e-boekhouden/relations`. MCP: `e_boekhouden_write → create_relation`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `name` | string | yes | Company or person name. |
| `type` | enum | no | B (business) or P (private). Default: B. |
| `address` | string | no | Primary address. |
| `postal_code` | string | no | Primary postal code. |
| `city` | string | no | Primary city. |
| `country` | string | no | Primary country. |
| `email` | string | no | Email address. |
| `email_invoice` | string | no | Email address for invoices. |
| `vat_number` | string | no | VAT number. |
| `iban` | string | no | IBAN. |
| `term_of_payment` | integer | no | Default payment term in days. |

Creates one relation. Only name is required; type defaults to business (B) and the code is generated if you leave it out. It reaches nobody and is undone in one call with update_relation (set inactive), so it does not wait for your OK. Check list_relations first so you do not create a duplicate.

Example response:

```json
{
  "relation_id": 1071,
  "code": "KRT001",
  "type": "B",
  "name": "Kraan Tuinen VOF",
  "inactive": false
}
```

### update_relation

Change fields of a relation, or set it inactive. Access: write. REST: `PATCH /api/v1/e-boekhouden/relations/{relation_id}`. MCP: `e_boekhouden_write → update_relation`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `relation_id` | integer | yes | Relation ID from list_relations. |
| `name` | string | no | New name. |
| `address` | string | no | Primary address. |
| `postal_code` | string | no | Primary postal code. |
| `city` | string | no | Primary city. |
| `email` | string | no | Email address. |
| `email_invoice` | string | no | Email address for invoices. |
| `vat_number` | string | no | VAT number. |
| `iban` | string | no | IBAN. |
| `term_of_payment` | integer | no | Default payment term in days. |
| `inactive` | boolean | no | true to retire the relation. |

Changes only the fields you pass and leaves the rest. Set inactive to true to retire a relation. It reaches nobody and the old values can be put back with another call, so it does not wait for your OK. Invoices already created keep their data.

Example response:

```json
{
  "relation_id": 1071,
  "name": "Kraan Tuinen VOF",
  "email_invoice": "boekhouding@kraantuinen.example",
  "inactive": false
}
```

### create_invoice

Create an invoice for a relation from one or more lines, and optionally email it to the relation. Access: write, asks the user first. REST: `POST /api/v1/e-boekhouden/relations/{relation_id}/invoices`. MCP: `e_boekhouden_write → create_invoice`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `relation_id` | integer | yes | Relation ID from list_relations. |
| `term_of_payment` | integer | yes | Payment term in days. |
| `template_id` | integer | yes | Template ID from list_invoice_templates. |
| `items` | array | yes | Lines: description, quantity, price_per_unit, vat_code, ledger_id, optional product_id, discount_amount or discount_percentage. vat_code is one of HOOG_VERK_21, LAAG_VERK_9, VERL_VERK, VERL_VERK_L9, AFW, BU_EU_VERK, BI_EU_VERK, BI_EU_VERK_D, AFST_VERK, GEEN. |
| `in_ex_vat` | enum | no | IN if line prices include VAT, EX if they exclude it. |
| `date` | date | no | Invoice date. Default: today. |
| `invoice_number` | string | no | Your own number, must end with a digit. Empty: next number. |
| `reference` | string | no | Payment reference. |
| `text` | string | no | Text on the invoice. |
| `send_email` | boolean | no | true to email the invoice to the relation now. Default: false. |

Creates one invoice in the books. Required: relation_id, term_of_payment in days, template_id and at least one line. Leave invoice_number empty and e-Boekhouden assigns the next one. Amounts are excluding or including VAT as in_ex_vat says; a line takes a fixed discount or a percentage, not both. Pass send_email to mail it to the relation straight away, otherwise it only exists in e-Boekhouden. The invoice is a legal document and cannot be edited or deleted through the API. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "invoice_id": 9021,
  "invoice_number": "2026-0143",
  "date": "2026-10-12",
  "relation_id": 1042,
  "total_excl_vat": 850,
  "vat": 178.5,
  "total_incl_vat": 1028.5,
  "emailed": false
}
```

### create_mutation

Book a mutation: a payment, money received or sent, or a general journal entry. Access: write, asks the user first. REST: `POST /api/v1/e-boekhouden/ledgers/{ledger_id}/mutations`. MCP: `e_boekhouden_write → create_mutation`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `type` | enum | yes | 1 to 7, see details. |
| `date` | date | yes | Date of the booking. |
| `ledger_id` | integer | yes | Ledger ID from list_ledgers. |
| `rows` | array | yes | Rows: amount, description, invoice_number (types 3 and 4), ledger_id (types 1, 2, 5, 6, 7), vat_code, relation_id, cost_center_id. |
| `description` | string | no | Description of the mutation. |
| `relation_id` | integer | no | Relation of the booking. |
| `invoice_number` | string | no | Invoice number of the mutation. |
| `in_ex_vat` | enum | no | IN if row amounts include VAT, EX if they exclude it. |
| `payment_reference` | string | no | Payment reference. |

Records one booking. type is 1 to 7: 1 invoice received, 2 invoice sent, 3 invoice payment received, 4 invoice payment sent, 5 money received, 6 money sent, 7 general journal entry. Required: type, date and ledger_id. Rows carry the amount, and for types 3 and 4 the invoice_number they pay. It changes your books and cannot be deleted through the API. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "mutation_id": 5513,
  "type": "3",
  "date": "2026-10-12",
  "ledger_id": 1155,
  "description": "Payout 12 Oct 2026",
  "rows": 1,
  "amount": 1028.5
}
```

## How do I connect e-Boekhouden to Claude Code, Codex or Cursor?

Connecting e-Boekhouden takes three steps: sign up, sign in to e-Boekhouden 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 e-Boekhouden to your agent.

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

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

```
Create an October 2026 invoice for each client on this list with the hours and rate next to their name. Use my standard template, 14 days payment term, 21% VAT. Show me the totals before sending.
```

### Call e-Boekhouden 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/e-boekhouden 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/e-boekhouden/relations/1042/invoices \
  -H "Authorization: Bearer $COTLET_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"template_id":3,"term_of_payment":14,"in_ex_vat":"EX","items":[{"description":"Consulting October 2026","quantity":10,"price_per_unit":85,"vat_code":"HOOG_VERK_21","ledger_id":8000}]}'
```

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

```
{
  "invoice_id": 9021,
  "invoice_number": "2026-0143",
  "date": "2026-10-12",
  "relation_id": 1042,
  "total_excl_vat": 850,
  "vat": 178.5,
  "total_incl_vat": 1028.5,
  "emailed": false
}
```

## Why use Cotlet for e-Boekhouden?

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

## Is it safe to connect e-Boekhouden to Cotlet?

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

No, Cotlet is independent of e-Boekhouden. e-Boekhouden's own API is too limited for this work. Cotlet works through your own e-Boekhouden account, the way you use e-Boekhouden 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 e-Boekhouden in your console: your agents lose access at once and you stay signed in. Signing out of e-Boekhouden in the browser works too, and Reset browser deletes the whole profile.

## Is there a e-Boekhouden MCP server on GitHub?

No open-source or official MCP server for e-Boekhouden turned up on 14 Oct 2026. The realistic route is the official REST API: you create a token, write the session-token and request code, and host it where your agent can reach it. Cotlet gives you the same operations as an MCP server and a REST API with one key and one sign-in.

|  | Official API | Cotlet |
|---|---|---|
| Setup | Create an API token in your account, exchange it for a session token, write and host the client code | Sign up, sign in to e-Boekhouden once, add one MCP server or API key |
| Tokens | API token is shown once and you store it in your own code or environment | No token to copy around; one Cotlet key for your agent and scripts |
| Your e-Boekhouden session | Not used; a long-lived API token stands in for it | Signed in inside your own Cloud Browser in the EU, profile encrypted with AES-256-GCM, no password saved, disabled for agents in one click |
| When the app changes | You update your code when the API changes | Our team tests it daily and fixes it for you; failed calls are free |
| MCP for AI agents | None from the vendor; you build the tool layer yourself | Ready: 14 tools with typed parameters for Claude Code, Codex, Cursor and others |
| Where it runs | Wherever you host your code | Hosted: MCP clients, n8n and scripts, also on a schedule |
| Price | Free to call, 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 e-Boekhouden 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 e-Boekhouden API cost?

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

**Do I need to be technical?**

No. You sign in to e-Boekhouden 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 e-Boekhouden to Cotlet?**

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

e-Boekhouden 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 a specific e-Boekhouden plan for the API?**

e-Boekhouden lists the API among the features on its pricing page but does not say there which plans include it (checked 14 Oct 2026). Cotlet works in your own account and does not use the API token, so your plan only needs to include the features you use.

**Can my agent send an invoice to a client without asking me?**

Only if you switch confirmation off for create_invoice. By default every create_invoice and create_mutation call waits for your OK, because an invoice is a legal document and a booking changes your books.

**Can my agent post or send messages in e-Boekhouden without asking me?**

No. Every call to create_invoice or create_mutation 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_relation, update_relation runs without asking, because it sends nothing to anyone and one call undoes it.

**Can I use the e-Boekhouden 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/e-boekhouden 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.