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# iFirma API

> Every iFirma endpoint on Cotlet: inputs, JSON Schema, cURL, Python and Node.js examples and an example response for each call.

Source: https://cotlet.dev/docs/api/ifirma

Docs sections: [Get started](https://cotlet.dev/docs.md) · [REST API](https://cotlet.dev/docs/api.md) · [MCP](https://cotlet.dev/docs/mcp.md) · [SDKs & CLI](https://cotlet.dev/docs/sdks.md) · [Integrations](https://cotlet.dev/docs/integrations.md)

14 endpoints for iFirma, each at its own method and path, called with your API key. Open an endpoint for its inputs, examples and response.

- Base URL: `https://cotlet.dev/api/v1/ifirma`
- Connects with: Your own iFirma account (the account holder; sales, KSeF and expenses must be part of your package)
- Integration page: https://cotlet.dev/integrations/ifirma-api-mcp-server

## Read

Return data and change nothing in the account.

| Endpoint | Description |
|---|---|
| [`GET /invoices`](https://cotlet.dev/docs/api/ifirma/list_invoices.md) | Sales invoices for a date range, with totals, payment and KSeF status. |
| [`GET /invoices/{invoice_id}`](https://cotlet.dev/docs/api/ifirma/get_invoice.md) | One invoice with its lines, buyer, payments and KSeF status. |
| [`GET /invoices/{invoice_id}/pdf`](https://cotlet.dev/docs/api/ifirma/get_invoice_pdf.md) | The invoice as a PDF file, base64 encoded. |
| [`GET /contractors`](https://cotlet.dev/docs/api/ifirma/list_contractors.md) | Contractors from your list, searchable by name or tax number. |
| [`GET /ksef-purchase-invoices`](https://cotlet.dev/docs/api/ifirma/list_ksef_purchase_invoices.md) | Invoices that suppliers sent to you in KSeF and you have not booked yet. |

## Write

Change the account. Calls marked Confirm wait for the user to approve them.

| Endpoint | Description |
|---|---|
| [`POST /postals/{postal_code}/contractors`](https://cotlet.dev/docs/api/ifirma/create_contractor.md) | Add a contractor to your iFirma list. |
| [`POST /contractors/{contractor_id}/invoice-draft/save`](https://cotlet.dev/docs/api/ifirma/save_invoice_draft.md) | Save an invoice as a draft without a number, to review and issue in the app. |
| [`POST /contractors/{contractor_id}/invoices`](https://cotlet.dev/docs/api/ifirma/issue_invoice.md) (Confirm) | Issue a domestic invoice for a contractor with one or more lines. |
| [`POST /invoices/{invoice_id}/to-ksef`](https://cotlet.dev/docs/api/ifirma/send_invoice_to_ksef.md) (Confirm) | Send one issued invoice to the Polish KSeF e-invoicing system. |
| [`POST /invoices/{invoice_id}/email`](https://cotlet.dev/docs/api/ifirma/send_invoice_email.md) (Confirm) | Email an issued invoice to the buyer, with the invoice attached. |
| [`POST /invoices/{invoice_id}/payments`](https://cotlet.dev/docs/api/ifirma/record_payment.md) (Confirm) | Record a payment received on an invoice. |
| [`POST /ksefs/{ksef_number}/purchase-invoice`](https://cotlet.dev/docs/api/ifirma/book_ksef_purchase_invoice.md) (Confirm) | Book a purchase invoice from KSeF as a cost. |
| [`POST /invoices/{invoice_number}/expenses`](https://cotlet.dev/docs/api/ifirma/add_expense.md) (Confirm) | Add a cost document by hand: goods purchase, business cost or phone and internet bill. |
| [`POST /invoices/{invoice_id}/payment-reminders`](https://cotlet.dev/docs/api/ifirma/send_payment_reminder.md) (Confirm) | Email a Ponaglenie, Monit or Wezwanie do zapłaty for an unpaid invoice. |

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## 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.