Authentication

All requests to /api/v1/* must include your Bearer API token in the HTTP Authorization header.

# HTTP Header
Authorization: Bearer biz_live_xxxxxxxxxxxxxxxxxxxxxxxx
GET POST /api/v1/invoices
Rate Limit: 100 req/min

List or create business invoices directly in your connected Google Sheet.

Request Example
curl http://localhost:3000/api/v1/invoices \
  -H "Authorization: Bearer biz_live_your_api_key_here" \
  -H "Content-Type: application/json"
Create Invoice POST Payload Example
{
  "customer_id": "cus_992288",
  "invoice_date": "2026-08-08",
  "due_date": "2026-08-22",
  "discount": "50.00",
  "items": [
    {
      "description": "Custom Software Development",
      "quantity": 10,
      "unit_price": 150.00,
      "tax_rate": 10
    }
  ]
}