PlugRail Japanese Calendar is a remote MCP server that gives an AI agent 4 tools, among them add_business_days, business_days_between, is_holiday. It answers at https://jp-calendar.plugrail.dev/mcp over streamable HTTP, and it listed its tools to an anonymous client, so no sign-in was needed for that. Our probes reached it 10 of 10 times since 5 September 2026; the last check, on 18 October 2026, succeeded.
Japanese holiday and business-day calculations using official Japan Cabinet Office data.
Description as the publisher wrote it.
| Tool | What it does |
|---|---|
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（days=0でも同じ情報がskipped経由で得られます）。入力例: {"date": Inputs: date, days, calendar, extra_closed_dates |
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 の場合はエラーにせず、from/toとinclude_from/include_toを入れ替えて計算した結果の符号を反転した値（負の営業日数） Inputs: from, to, calendar, extra_closed_dates, include_from, include_to |
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"} Inputs: date |
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"} Inputs: year, from, to |
Every block below points at https://jp-calendar.plugrail.dev/mcp. Pick your client and copy.
claude mcp add --transport http plugrail-japanese-calendar https://jp-calendar.plugrail.dev/mcp
{
"mcpServers": {
"plugrail-japanese-calendar": {
"command": "npx",
"args": ["-y", "mcp-remote", "https://jp-calendar.plugrail.dev/mcp"]
}
}
}{
"mcpServers": {
"plugrail-japanese-calendar": {
"url": "https://jp-calendar.plugrail.dev/mcp"
}
}
}{
"servers": {
"plugrail-japanese-calendar": {
"type": "http",
"url": "https://jp-calendar.plugrail.dev/mcp"
}
}
}{
"context_servers": {
"plugrail-japanese-calendar": {
"url": "https://jp-calendar.plugrail.dev/mcp"
}
}
}{
"mcpServers": {
"plugrail-japanese-calendar": {
"serverUrl": "https://jp-calendar.plugrail.dev/mcp"
}
}
}{
"mcpServers": {
"plugrail-japanese-calendar": {
"url": "https://jp-calendar.plugrail.dev/mcp"
}
}
}name: PlugRail Japanese Calendar
version: 0.0.1
schema: v1
mcpServers:
- name: PlugRail Japanese Calendar
type: streamable-http
url: https://jp-calendar.plugrail.dev/mcp{
"mcpServers": {
"plugrail-japanese-calendar": {
"httpUrl": "https://jp-calendar.plugrail.dev/mcp"
}
}
}{
"mcpServers": {
"plugrail-japanese-calendar": {
"type": "http",
"url": "https://jp-calendar.plugrail.dev/mcp"
}
}
}{
"mcpServers": {
"plugrail-japanese-calendar": {
"url": "https://jp-calendar.plugrail.dev/mcp"
}
}
}goose://extension?url=https%3A%2F%2Fjp-calendar.plugrail.dev%2Fmcp&type=streamable_http&id=plugrail-japanese-calendar&name=PlugRail%20Japanese%20Calendar
It answered our last check on 18 October 2026 in 1012 ms. Over 10 checks since 5 September 2026 it answered 10. Status here comes from Neuronto's own probes, not from the publisher.
Yes. It is published by plugrail.dev and served from jp-calendar.plugrail.dev, the vendor's own domain: https://jp-calendar.plugrail.dev/mcp.
4, as returned by the server's own tools/list on 31 August 2026: add_business_days, business_days_between, is_holiday, list_holidays.
It answered our last check on 18 October 2026 in 1012 ms. Over 10 checks since 5 September 2026 it answered 10.
Put the server under mcpServers in ~/.cursor/mcp.json with the URL https://jp-calendar.plugrail.dev/mcp. The exact JSON is above, with the same setup for Claude Code, Claude Desktop, VS Code, Windsurf, Zed, Gemini CLI and the rest.
It listed its tools to an anonymous client, so reading the tool list needs no key. Individual tools can still ask for credentials in their own inputs.
Publisher: dev.plugrail. Endpoint host: jp-calendar.plugrail.dev. ARD identifier: urn:air:dev.plugrail:mcp:jp-calendar.
First indexed 31 August 2026. The tools are exactly what the server returned; nothing on this page
is inferred from its name. Ranking in Neuronto search is never for sale.