# PlugRail Japanese Calendar (remote · jp-calendar.plugrail.dev)

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

- Trust score: 60/100 (medium)
- Change this week: +2
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-03

## Components

- remote · `jp-calendar.plugrail.dev`: 60/100 (this document), [markdown](https://verifymcp.io/servers/dev-plugrail-jp-calendar/jp-calendar.md), [page](https://verifymcp.io/servers/dev-plugrail-jp-calendar/jp-calendar)

## Channel facts

- Endpoint: `https://jp-calendar.plugrail.dev/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `0.1.1`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-08-03.

- **Endpoint Security**: 46/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation not fully verified: no authorisation is required to call this server, and 4 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe.
  - HTTPS not yet verified: we couldn't determine whether a plaintext access path exists.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 63/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 986 tokens (~246/item across 4 items; 4 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 27/100
  - Stability observed for 8 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### Claude

```bash
claude mcp add --transport http dev-plugrail-jp-calendar https://jp-calendar.plugrail.dev/mcp
```

### Codex

```toml
[mcp_servers.dev-plugrail-jp-calendar]
url = "https://jp-calendar.plugrail.dev/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "dev-plugrail-jp-calendar": {
      "type": "remote",
      "url": "https://jp-calendar.plugrail.dev/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add dev-plugrail-jp-calendar --url https://jp-calendar.plugrail.dev/mcp --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  dev-plugrail-jp-calendar:
    url: "https://jp-calendar.plugrail.dev/mcp"
```

### Other

```json
{
  "mcpServers": {
    "dev-plugrail-jp-calendar": {
      "type": "http",
      "url": "https://jp-calendar.plugrail.dev/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-08-03 (score 60, +1)

No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-08-02 (score 59, 0)

- [functional regression] Schema quality: 212 → 246

### 2026-07-31 (score 59, −1)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-29 (score 60, +1)

No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-28 (score 59, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-27 (score 58, 0)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-26 (score 58)

First indexed and scored.

## MCP tools (4)

### `is_holiday` (~87 tokens)

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"}

Input parameters:

- `date` (string, required): YYYY-MM-DD形式の日付。例: "2026-01-01"

### `list_holidays` (~149 tokens)

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"}

Input parameters:

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

### `add_business_days` (~331 tokens)

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": "2026-07-10", "days": 3}

Input parameters:

- `calendar` (string): "standard"（既定）または"banking"（銀行休業日も除外）。
- `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も指定可: dateをそのまま返し、dateが非営業日ならskippedに1件（date自身とその理由）を記録します。
- `extra_closed_dates` (array): 顧客固有の追加休業日（YYYY-MM-DD の配列）。例: ["2026-12-29", "2026-12-30"]

### `business_days_between` (~419 tokens)

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）を返します（反対称則: count(A,B,x,y) = -count(B,A,y,x)。A≠B、すなわちfrom≠toの場合に成立する恒等式で、from===toはこの分岐に入らないため対象外）。入力例: {"from": "2026-07-10", "to": "2026-07-20"}

Input parameters:

- `calendar` (string): "standard"（既定）または"banking"（銀行休業日も除外）。
- `extra_closed_dates` (array): 顧客固有の追加休業日（YYYY-MM-DD の配列）。例: ["2026-12-29", "2026-12-30"]
- `from` (string, required): 起点日 YYYY-MM-DD。例: "2026-07-10"。
- `include_from` (boolean): fromを営業日数に含めるか。既定はfalse。
- `include_to` (boolean): toを営業日数に含めるか。既定はtrue。
- `to` (string, required): 終点日 YYYY-MM-DD。例: "2026-07-20"。fromより前の日付も指定可（結果は負の営業日数になります）。

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/dev-plugrail-jp-calendar/jp-calendar#diagnostics

## Score history

- 2026-08-03: 60
- 2026-08-02: 59
- 2026-08-01: 59
- 2026-07-31: 59
- 2026-07-30: 60
- 2026-07-29: 60
- 2026-07-28: 59
- 2026-07-27: 58
- 2026-07-26: 58

## Links

- Remote endpoint: https://jp-calendar.plugrail.dev/mcp
- Repository: https://github.com/plugrail/servers
- Website: https://plugrail.dev/
- Changelog RSS feed: https://verifymcp.io/servers/dev-plugrail-jp-calendar/jp-calendar/changelog.xml
- Changelog JSON feed: https://verifymcp.io/servers/dev-plugrail-jp-calendar/jp-calendar/changelog.json
- HTML version of this page: https://verifymcp.io/servers/dev-plugrail-jp-calendar/jp-calendar