{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "period": {
      "description": "Billing month in UTC, formatted YYYY-MM; defaults to the current month.",
      "type": "string",
      "pattern": "^\\d{4}-\\d{2}$"
    }
  },
  "additionalProperties": false
}