{
  "slug": "date-calculator",
  "mcpServerUrl": "https://plugins-worker.demos.42a.ai/date-calculator/mcp",
  "interface": {
    "displayName": "Handy Date Calculator",
    "shortDescription": "Days, business days, holidays",
    "longDescription": "Count the days between two dates, add days, weeks, months or business days to a date, and look up public holidays, with exact answers and a mini calendar.\n\nAsk \"how many business days between Oct 1 and Dec 31 in the US\", \"how many days until Christmas\", \"what date is 30 working days from today in the UK\" or \"what is 6 months after August 31\". The card shows calendar days, weeks and days, months and days, and business days, skipping weekends and the official public holidays of your country (and state or region, if you give one). Month-end dates are handled properly (Jan 31 plus one month is the last day of February).\n\nHolidays come from the open Nager.Date database (over 100 countries). Only official public holidays count as days off; bank-only, school and observance days are listed separately. Download a country's holidays as a calendar file. Nothing is stored.",
    "category": "Productivity",
    "defaultPrompt": [
      "How many business days are there between Oct 1 and Dec 31, 2026 in the US, including both dates?",
      "How many days until Christmas?",
      "What date is 10 working days after December 18 in England?"
    ],
    "capabilities": [
      "Days between two dates in days, weeks, months and business days",
      "Countdowns to any date from today in your time zone",
      "Adds days, weeks, months, years or business days to a date",
      "Skips official public holidays for 100+ countries and their regions",
      "Lists a year of public holidays with the next one coming up",
      "Mini calendar plus a holiday calendar file"
    ],
    "logo": "https://plugins-worker.demos.42a.ai/date-calculator/icon.svg",
    "websiteURL": "https://plugins-worker.demos.42a.ai/date-calculator/",
    "supportURL": "https://plugins-worker.demos.42a.ai/support",
    "privacyPolicyURL": "https://plugins-worker.demos.42a.ai/privacy",
    "termsOfServiceURL": "https://plugins-worker.demos.42a.ai/terms",
    "developerName": "42a"
  },
  "keywords": [
    "days between dates",
    "how many days until",
    "business days calculator",
    "working days between two dates",
    "add business days to a date",
    "date calculator",
    "public holidays this year",
    "how many weeks until",
    "what date is 90 days from today"
  ],
  "tools": [
    {
      "name": "days_between",
      "title": "Days between dates",
      "annotations": {
        "readOnlyHint": true,
        "destructiveHint": false,
        "openWorldHint": true
      }
    },
    {
      "name": "add_to_date",
      "title": "Add to a date",
      "annotations": {
        "readOnlyHint": true,
        "destructiveHint": false,
        "openWorldHint": true
      }
    },
    {
      "name": "list_holidays",
      "title": "List public holidays",
      "annotations": {
        "readOnlyHint": true,
        "destructiveHint": false,
        "openWorldHint": true
      }
    }
  ],
  "dataSources": [
    {
      "name": "Nager.Date",
      "url": "https://date.nager.at",
      "purpose": "Public holidays by country, year and region (country code and year only are sent)."
    }
  ],
  "review": {
    "positiveTestCases": [
      {
        "description": "Business days in a quarter, US federal holidays",
        "prompt": "How many business days are there between Oct 1 and Dec 31, 2026 in the US, including both dates?",
        "tools_triggered": [
          "days_between"
        ],
        "expected_behavior": "Hero shows 63 business days out of 92 calendar days, skipping Veterans Day, Thanksgiving and Christmas (Columbus Day is bank-only nationally, so it is not skipped)."
      },
      {
        "description": "Countdown to Christmas from today",
        "prompt": "How many days until Christmas?",
        "tools_triggered": [
          "days_between"
        ],
        "expected_behavior": "Hero shows 85 days until Christmas, counted from today (Thu, Oct 1, 2026 in New York)."
      },
      {
        "description": "Business days forward across Christmas in England",
        "prompt": "What date is 10 working days after December 18, 2026 in England?",
        "tools_triggered": [
          "add_to_date"
        ],
        "expected_behavior": "Wednesday, Jan 6, 2027: Christmas Day, the Boxing Day substitute (Dec 28) and New Year's Day are skipped."
      },
      {
        "description": "Month-end clamping",
        "prompt": "What is the date 6 months after August 31, 2026?",
        "tools_triggered": [
          "add_to_date"
        ],
        "expected_behavior": "Sunday, Feb 28, 2027 (February has no 31st), flagged as a weekend."
      },
      {
        "description": "A year of regional holidays",
        "prompt": "What are the public holidays in Bavaria in 2026, and when is the next one?",
        "tools_triggered": [
          "list_holidays"
        ],
        "expected_behavior": "Lists 12 public holidays (9 national plus Epiphany, Corpus Christi and All Saints' Day for Bavaria); the next is German Unity Day, Sat Oct 3, in 2 days. Offers an .ics download."
      }
    ],
    "negativeTestCases": [
      {
        "prompt": "What time is it in Tokyo when it is 3 PM in New York?",
        "expected_behavior": "Does not call Handy Date Calculator: Converting clock times between time zones is not date arithmetic."
      },
      {
        "prompt": "Add my dentist appointment on March 3 at 2 PM to my calendar.",
        "expected_behavior": "Does not call Handy Date Calculator: Creating a calendar event is not counting days."
      },
      {
        "prompt": "How old will I be in 2040 if I was born in 1990?",
        "expected_behavior": "Does not call Handy Date Calculator: Simple year subtraction the model answers directly; no dates or holidays involved."
      }
    ]
  }
}