Japan Business Calendar Mcp

io.github.atushi1841Published by GitHub account atushi1841v0.1.0Updated Oct 29, 2026

Japan business day & holiday calculator MCP. Official holidays + business-day arithmetic, 6 tools.

VerifiedSTDIODesktop onlyLocation & LifestyleProductivity & Workflow

Overview

AI-generated overview

Offline MCP server that gives an assistant Japan's official national holidays and business-day arithmetic for dates from 1955 to 2027.

What you can do
  • Classify a date as business day, national holiday or weekend, and find the nearest business days
  • Count business days within a date range, or step n business days forward or back
  • List all national holidays, optionally filtered by year, and list every business day in a given month
  • Report the bundled dataset's source, license and coverage
When to use it
Useful when scheduling, deadline or delivery-date work depends on Japanese working days, such as planning around Golden Week or year-end holidays, or checking whether a specific date is a working day in Japan.
Requirements
Runs as a local process on the user's machine (stdio); the README shows starting it with uv run. Holiday data is bundled, so no network access, account or API key is needed at runtime. Desktop clients only.
Before you install
Holiday data is a bundled snapshot covering 1955-01-01 to 2027-11-23, so dates outside that range or later official changes are not reflected. Business days are defined only as non-holiday weekdays, ignoring company-specific calendars. The README also mentions a paid managed Apify Actor option; the local package itself needs no payment.

Installation

In SourceWeft

  1. Open Japan Business Calendar Mcp 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

Japan Business Day & Holiday Calculator MCP

MCP server exposing Japan's official national holidays and business-day arithmetic to AI agents. Data is the Cabinet Office (内閣府) official 国民の祝日・休日 list — deterministic, offline-safe, no network at runtime.

What it does

ToolDescription
analyze_dateIs a date a business day, a national holiday, or a weekend? Nearest business days.
count_business_daysInclusive business-day count over a date range.
next_business_dayn-th business day before/after a date.
list_holidaysFull national holiday list, optionally filtered by year.
list_business_daysAll business days in a Japanese calendar month.
data_summarySeed metadata: source, license, coverage.

REST mirror (OpenAPI): /rest/analyze, /rest/count, /rest/next, /rest/holidays, /rest/business-days, /rest/summary, /health, /openapi.json.

Data & attribution

  • Source: Cabinet Office (内閣府) 国民の祝日・休日 — https://www8.cao.go.jp/chosei/shukujitsu/syukujitsu.csv
  • License: Government Standard Terms of Use (出典明示で商用利用可)
  • Coverage: 1955-01-01 → 2027-11-23 (1,067 holidays), bundled as data/japan_holidays.json (~63 KB).
  • Business-day rule: not a national holiday and not Saturday/Sunday.

Local run

bash
uv run --directory . src/stdio_main.py        # stdio MCP (Claude Desktop / Cursor)JBC_DATA_DIR=. python3 tests/test_jbc.py       # smoke: 6 MCP tools + 8 REST endpoints

Deployment

Apify Actor japan-business-calendar-mcp (Standby mode, webServerMcpPath=/mcp, Dockerfile CMD ["python", "-m", "src.main"]): https://fruitful-quintessence--japan-business-calendar-mcp.apify.actor/mcp

Apify Store

This MCP server is also available as a managed Apify Actor (PPE课金):

  • Apify Store: japan-business-calendar-mcp — Japanese business days & national holidays from the Cabinet Office official list. Run from the Apify Store (Run button), then point your MCP client at the endpoint.

Install via Smithery

Connect this MCP server to your AI client (Claude Desktop, Cursor, VS Code) in one command:

bash
npx @smithery/cli install atushi1841/japan-business-calendar-mcp --client claude

Replace claude with cursor, vscode, or cline for other clients.

Alternatively, install directly from the Smithery registry.

MCP Registry

This server is registered on the official MCP Registry. Find it via search: japan-business-calendar-mcp

Source: README.md at commit 64cfd28

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v0.1.0LatestOct 29, 2026

Score

40% 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

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • 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 listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts

    Declare a license in the repository or the registry entry.