Invoice123

Invoice123

This connector reads Invoice123 (app.invoice123.com, Saskaita123 in Lithuania), the invoicing and bookkeeping service for small businesses in Lithuania and Latvia, through its REST API v1.0: sales invoices and their payments and PDFs, purchases, clients, products, projects, waybills and the reference data (series, VAT rates, banks, units, activities). It is read-only.

Setup (about 2 minutes)

1. In Invoice123 open the account menu (top right), Integrations (puzzle icon) or Account settings > Integrations, and install the API integration.
2. Click Generate your API key, name it and tick the permissions the AI may use, at least invoice:index, plus expense:index, client:index, product:index, project:index and waybills:index for those areas. The PDF route of invoices checks invoice:store, and the offer PDF commercial:store.
3. Paste the key into INVOICE123_API_TOKEN. It is sent as Authorization: Bearer.
4. Install and run invoice123_get_company to check the token.

Workflow

• Reference data first when you need ids: invoice123_get_invoice_data (activities, series, banks, units, VAT rates, warehouses in one call), or invoice123_list_series, invoice123_list_bank_accounts, invoice123_list_units, invoice123_list_activities, invoice123_list_cash_registers, invoice123_list_email_templates, invoice123_list_invoice_vat_rates.
• Sales: invoice123_list_invoices (filter by status unpaid or late for open items, range for a period, client_id for one customer), invoice123_list_invoice_payments to see how and when an invoice was paid (transfer, cash, card, cash register receipt), invoice123_get_invoice_payment_link, invoice123_download_invoice_pdf.
• Purchases: invoice123_list_purchases, invoice123_list_purchase_types, invoice123_list_purchase_vat_rates.
• Master data: invoice123_list_clients (customers and suppliers), invoice123_list_products, invoice123_list_projects, invoice123_list_waybills; offers: invoice123_download_commercial_offer_pdf.

Paging: lists return data.result and data.pagination (current_page, last_page, total); pass page (from 1) and limit (default 20) and stop at last_page. Date ranges are two YYYY-MM-DD dates joined by a comma. Amounts are strings in the invoice currency (usually EUR).

Limits and errors: 60 requests per minute on the Standard plan, 1,000 per hour on Business (429 above that). 401 means a wrong or deleted token; 403 means the token lacks the permission named in the tool description; purchases, waybills and offers also need their module enabled in the account.