curl --request POST \
  --url https://api.iotools.cloud/v1/tool/date-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "startDate": "1990-06-15",
  "operation": "add",
  "years": "2",
  "months": "3",
  "days": "10"
}
'

{
  "tool": "date-calculator",
  "tool_version": "1.0.1",
  "outputs": {
    "result": [
      {
        "metric": "Start Date",
        "value": "Friday, June 15, 1990"
      },
      {
        "metric": "Operation",
        "value": "Added 2 years, 3 months, 10 days"
      },
      {
        "metric": "Result Date",
        "value": "Friday, September 25, 1992"
      },
      {
        "metric": "Day of Week",
        "value": "Friday"
      },
      {
        "metric": "ISO Format",
        "value": "1992-09-25"
      },
      {
        "metric": "Total Days",
        "value": "833 days"
      },
      {
        "metric": "In Weeks",
        "value": "119 weeks and 0 days"
      }
    ]
  },
  "credits_used": 3,
  "credits_remaining": null
}