PlugRail Japanese Calendar

Official4 toolsLive

by plugrail · TypeScript

Japanese holiday and business-day calculations using official Japan Cabinet Office data.

Captured live from the server via tools/list.

is_holiday

指定した日付が日本の祝日（国民の祝日・休日）かどうかを判定します。内閣府公表データに基づきます。入力例: {"date": "2026-01-01"}

Parameters1

date

string

required

YYYY-MM-DD形式の日付。例: "2026-01-01"

Raw schema

{
  "type": "object",
  "properties": {
    "date": {
      "type": "string",
      "description": "YYYY-MM-DD形式の日付。例: \"2026-01-01\""
    }
  },
  "required": [
    "date"
  ],
  "$schema": "http://json-schema.org/draft-07/schema#"
}

list_holidays

指定した年または期間の日本の祝日一覧を返します。入力例: {"year": 2026} または {"from": "2026-01-01", "to": "2026-06-30"}

Parameters3

year	integer	optional	西暦年。例: 2026。from/toとは併用不可。
from	string	optional	期間開始日 YYYY-MM-DD。例: "2026-01-01"。yearとは併用不可。
to	string	optional	期間終了日 YYYY-MM-DD。例: "2026-06-30"。yearとは併用不可。

Raw schema

{
  "type": "object",
  "properties": {
    "year": {
      "description": "西暦年。例: 2026。from/toとは併用不可。",
      "type": "integer",
      "minimum": -9007199254740991,
      "maximum": 9007199254740991
    },
    "from": {
      "description": "期間開始日 YYYY-MM-DD。例: \"2026-01-01\"。yearとは併用不可。",
      "type": "string"
    },
    "to": {
      "description": "期間終了日 YYYY-MM-DD。例: \"2026-06-30\"。yearとは併用不可。",
      "type": "string"
    }
  },
  "$schema": "http://json-schema.org/draft-07/schema#"
}

add_business_days

指定した日付(date)の翌日から数えてN営業日目(days)の日付を返します。dateの当日は数えません。daysが負の場合は過去方向（dateの前日から遡ってN営業日目）に計算します。土日・日本の祝日を除外し、calendar="banking"を指定すると銀行休業日（12/31〜1/3）も除外します。dateが営業日かどうかだけ知りたい場合は is_holiday を使ってください。入力例: {"date": "2026-07-10", "days": 3}

Parameters4

date	string	required	起点日 YYYY-MM-DD。例: "2026-07-10"。この日自体は数えません。
days	number	required	何営業日先(正)/前(負)かを表す整数。0は不可（is_holidayまたはdays=1を使用）。
calendar	string	optional	"standard"（既定）または"banking"（銀行休業日も除外）。
extra_closed_dates	array	optional	顧客固有の追加休業日（YYYY-MM-DD の配列）。例: ["2026-12-29", "2026-12-30"]

Raw schema

{
  "type": "object",
  "properties": {
    "date": {
      "type": "string",
      "description": "起点日 YYYY-MM-DD。例: \"2026-07-10\"。この日自体は数えません。"
    },
    "days": {
      "type": "number",
      "description": "何営業日先(正)/前(負)かを表す整数。0は不可（is_holidayまたはdays=1を使用）。"
    },
    "calendar": {
      "description": "\"standard\"（既定）または\"banking\"（銀行休業日も除外）。",
      "type": "string"
    },
    "extra_closed_dates": {
      "description": "顧客固有の追加休業日（YYYY-MM-DD の配列）。例: [\"2026-12-29\", \"2026-12-30\"]",
      "type": "array",
      "items": {
        "type": "string"
      }
    }
  },
  "required": [
    "date",
    "days"
  ],
  "$schema": "http://json-schema.org/draft-07/schema#"
}

business_days_between

from〜to間の営業日数を数えます。既定では「fromを含まず、toを含む」境界です（例:「今日から支払期日まで何営業日か」）。include_from/include_toで境界を変更できます。土日・日本の祝日を除外し、calendar="banking"を指定すると銀行休業日（12/31〜1/3）も除外します。from > to はエラーになります（負の期間は未対応）。入力例: {"from": "2026-07-10", "to": "2026-07-20"}

Parameters6

from	string	required	起点日 YYYY-MM-DD。例: "2026-07-10"。
to	string	required	終点日 YYYY-MM-DD。例: "2026-07-20"。fromより前の日付は不可。
calendar	string	optional	"standard"（既定）または"banking"（銀行休業日も除外）。
extra_closed_dates	array	optional	顧客固有の追加休業日（YYYY-MM-DD の配列）。例: ["2026-12-29", "2026-12-30"]
include_from	boolean	optional	fromを営業日数に含めるか。既定はfalse。
include_to	boolean	optional	toを営業日数に含めるか。既定はtrue。

Raw schema

{
  "type": "object",
  "properties": {
    "from": {
      "type": "string",
      "description": "起点日 YYYY-MM-DD。例: \"2026-07-10\"。"
    },
    "to": {
      "type": "string",
      "description": "終点日 YYYY-MM-DD。例: \"2026-07-20\"。fromより前の日付は不可。"
    },
    "calendar": {
      "description": "\"standard\"（既定）または\"banking\"（銀行休業日も除外）。",
      "type": "string"
    },
    "extra_closed_dates": {
      "description": "顧客固有の追加休業日（YYYY-MM-DD の配列）。例: [\"2026-12-29\", \"2026-12-30\"]",
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "include_from": {
      "description": "fromを営業日数に含めるか。既定はfalse。",
      "type": "boolean"
    },
    "include_to": {
      "description": "toを営業日数に含めるか。既定はtrue。",
      "type": "boolean"
    }
  },
  "required": [
    "from",
    "to"
  ],
  "$schema": "http://json-schema.org/draft-07/schema#"
}

README.md2 KBView on GitHub

plugrail

A collection of MCP servers that connect to Japanese public data. The name alone does not describe the project, so plugrail is not related to railways or railway services.

Live servers

Server	MCP endpoint	Tools	Status
jp-calendar	`https://jp-calendar.plugrail.dev/mcp`	`is_holiday`, `list_holidays`, `business_days_between`, `add_business_days`	Live

Connect

See the jp-calendar connection guide.

Self-hosting

In packages/servers/jp-calendar/, copy wrangler.example.jsonc to wrangler.jsonc and fill in your Cloudflare resource IDs.
Create the D1 database and KV namespace referenced by that configuration.
Run pnpm --filter @plugrail/jp-calendar deploy.

The self-hosted server runs independently. Authentication, rate limiting, and usage metering are features of the hosted service only.

Architecture

text

MCP client
    |
    v
jp-calendar Worker --> Cloudflare D1 (holiday data)
                   --> Cloudflare KV (cached data)

Sources and disclaimer

This is not an official service of the National Tax Agency, the Digital Agency, or any other Japanese government body. Information provided does not represent their official views and is not guaranteed by them.

Source: Adapted from the Cabinet Office "National Holidays" page (https://www8.cao.go.jp/chosei/shukujitsu/gaiyou.html)

Contributing

Issues and pull requests are welcome. Please include enough context to reproduce a problem or explain a proposed change.

License

MIT. See LICENSE.

Install

Tools (4)

is_holidaylist_holidaysadd_business_daysbusiness_days_between

Remote endpoint

Streamable HTTP

Hosted server - connect over the network, no local install.

url

https://jp-calendar.plugrail.dev/mcp

Add to VS Code Add to Cursor

claude_desktop_config.json

json

{
  "mcpServers": {
    "jp-calendar": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://jp-calendar.plugrail.dev/mcp"
      ]
    }
  }
}

Desktop config is stdio-only; this bridges via mcp-remote. Native remote: Settings > Connectors.