{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "#/components/schemas/Invoice",
  "title": "Invoice",
  "type": "object",
  "description": "An invoice record associated with a sales order.",
  "properties": {
    "entity_id": {
      "type": "integer",
      "description": "Numeric invoice entity ID."
    },
    "order_id": {
      "type": "integer",
      "description": "Numeric entity ID of the parent order."
    },
    "increment_id": {
      "type": "string",
      "description": "Human-readable invoice number."
    },
    "state": {
      "type": "integer",
      "description": "Invoice state. 1 = open, 2 = paid, 3 = cancelled.",
      "enum": [
        1,
        2,
        3
      ]
    },
    "grand_total": {
      "type": "number",
      "description": "Invoice grand total."
    },
    "subtotal": {
      "type": "number",
      "description": "Invoice subtotal."
    },
    "created_at": {
      "type": "string",
      "format": "date-time",
      "description": "ISO 8601 timestamp when the invoice was created."
    }
  }
}