World Business Calendar

io.github.groove79Published by GitHub account groove79v0.1.0Updated Oct 29, 2026

Public holidays and working-day math for 200+ countries and regions, local weekends. No keys.

VerifiedSTDIODesktop onlyLocation & LifestyleProductivity & Workflow

Overview

AI-generated overview

Offline MCP server that gives an assistant public holidays and working-day math for 200+ countries and regions, using each country's local weekends.

What you can do
  • List public, bank and optional holidays for a country or region in a given year, with English and local names and observed days
  • Check whether a date is a working day in a country and get the next and previous working days
  • Add or subtract working days from a date, or count working days between two dates
  • Find dates that are working days in all of several countries at once
  • List supported country codes and their state or region codes
When to use it
Useful when scheduling across countries: meeting dates for distributed teams, delivery ETAs, contract or payment deadlines, SLA due dates, payroll, shipping cut-offs and market-closed days. It helps when the assistant needs reliable local weekend and holiday rules rather than guessing dates.
Requirements
Runs locally over stdio, typically via npx with the npm package @appmonster/mcp-world-calendar, so Node.js is needed. No API keys or environment variables are declared, and the README says it works offline. A hosted HTTP endpoint is also mentioned in the README.
Before you install
The server only reads calendar data and has no declared credentials, so risk is low. Holiday data comes from a third-party dataset and may not reflect last-minute government changes, so verify critical deadlines. The README also mentions a hosted endpoint; using it would send queries to that third party instead of running locally.

Installation

In SourceWeft

  1. Open World Business Calendar in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

World Business Calendar MCP

Agents get dates wrong. This server answers "is it a working day there?" and "what date is 5 business days from now?" for 200+ countries and their states/regions, with local weekends (Friday–Saturday in Saudi Arabia, Israel, Egypt; Friday in Iran) and observed/substitute holidays. Offline, no API keys.

bash
npx -y @appmonster/mcp-world-calendar

Hosted (no install): https://okagent.kr/api/mcp (Streamable HTTP) — or REST https://okagent.kr/api/tools.

ToolWhat it does
world_list_holidaysHolidays of a country/region for a year (English + local names, public/bank/optional)
world_is_business_dayWorking day or not, next/previous working day (default: today in that country)
world_add_business_daysAdd/subtract N working days, or count working days between two dates
world_common_business_daysDates that are working days in all of several countries (cross-border meetings, settlements)
world_list_countriesSupported country and region codes

Claude Desktop config:

json
{ "mcpServers": { "world-calendar": { "command": "npx", "args": ["-y", "@appmonster/mcp-world-calendar"] } } }

Data: date-holidays (ISC code, holiday data CC-BY-3.0, © commenthol and contributors). Korea uses the K-MCP Korean engine (includes 2026 changes). Part of K-MCP. MIT.

Source: packages/world-calendar/README.md at commit 53af4ba

Tools

5

world_list_holidays

List public holidays of a country (and optionally a state/region) for a year, with English and local names and substitute (observed) days. 200+ countries. Use for scheduling across countries, shipping cut-offs, payroll or market-closed days. Set types to include bank/optional/observance days.

Parametersyearrequiredtypesregioncountryrequired

world_is_business_day

Tell whether a date is a working day in a country (not a weekend there, not a public holiday), and give the next and previous working days. Knows local weekends (Friday–Saturday in Saudi Arabia, Israel, Egypt…). Default date is today in that country.

ParametersdateregioncountryrequiredincludeBankextraHolidays

world_add_business_days

Add or subtract N working days in a country (skipping its weekends and public holidays), or count working days between two dates. Use for delivery ETAs, contract or payment deadlines, SLA due dates. Needs country, from (default today there) and either days or to.

ParameterstodaysfromregioncountryrequiredincludeBankextraHolidays

world_common_business_days

Find dates that are working days in ALL of several countries (e.g. US, DE and JP teams), between two dates — for meetings, settlements or launches across borders. Max 10 countries, 92 days.

Parameterstorequiredfromrequiredcountriesrequired

world_list_countries

List supported country codes (200+) or, with country, its state/region codes for regional holidays.

Parameterssearchcountry

Version history

1
  1. v0.1.0LatestOct 23, 2026

Score

90% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts
  • Auth declared10 pts

    Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.

  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts