ベストカレンダー 暦データ
jp.bestcalendar/koyomibestcalendar.jpstreamable-httpv1.0.0Scanned
Japanese calendar data (rokuyo, lucky days, solar terms, holidays, moon, sunrise), 1926-2080.
16 tools: 4 change things and 12 only read.
- Reads private data · 0
- Reads text others write · 0
- Can send data out · 0
- 2 findings
Anlyon alternative
4 of these tools change something. Run those as governed actions.
Declare what an action changes, and Anlyon puts it under a shared limit, binds every approval to the exact request, and grades the outcome. It works on any HTTPS API you can describe as an action.
Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.
Import an OpenAPI spec →Tools
Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.
16 tools
Changes things 4Claude Code: ask
add_days日付の N 日後・N 日前、または N 営業日後・前（business: true。土日祝を除く。定休の曜日・お盆・年末年始・個別の指定も可）。基準日は数えない。締め切りの逆算は n を負に。1 finding
Why it is in this group
- The name "add_days" says "add": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
The server marks "add_days" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
What this check looks forMatched text
annotations: {"readOnlyHint":true,"openWorldHint":false}; The name "add_days" says "add": a word for a change.
Description, as the server wrote it 日付の N 日後・N 日前、または N 営業日後・前（business: true。土日祝を除く。定休の曜日・お盆・年末年始・個別の指定も可）。基準日は数えない。締め切りの逆算は n を負に。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
answer日本語の質問 1 つ（例: 2027年4月の一粒万倍日はいつ？／2026年10月1日の六曜は？／2027年の夏至の時刻は？／1990年5月23日から20営業日後は？）に、答え・根拠の道具と引数・出典を 1 回で返す。規則で読むので、読めない質問には推測せず「読めませんでした」と聞き方の例を返す（そのときは他の道具を直接使う）。No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it 日本語の質問 1 つ（例: 2027年4月の一粒万倍日はいつ？／2026年10月1日の六曜は？／2027年の夏至の時刻は？／1990年5月23日から20営業日後は？）に、答え・根拠の道具と引数・出典を 1 回で返す。規則で読むので、読めない質問には推測せず「読めませんでした」と聞き方の例を返す（そのときは他の道具を直接使う）。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
check_business_day日付（または 62 日までの期間）が営業日か休みか（理由と祝日名）。1 日だけなら次の営業日・前の営業日も返す。休みの規則は既定で土日祝、定休の曜日・お盆・年末年始・個別の休業日と営業日を指定できる。No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Description, as the server wrote it 日付（または 62 日までの期間）が営業日か休みか（理由と祝日名）。1 日だけなら次の営業日・前の営業日も返す。休みの規則は既定で土日祝、定休の曜日・お盆・年末年始・個別の休業日と営業日を指定できる。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
convert_wareki_eto西暦の年（1926〜2080）を和暦（改元の年は両方）・十干十二支・年の九星に、または日付を和暦・本命星・月命星に換算する。year か date のどちらかを指定。1 finding
Why it is in this group
- The name "convert_wareki_eto" says "convert": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
The server marks "convert_wareki_eto" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
What this check looks forMatched text
annotations: {"readOnlyHint":true,"openWorldHint":false}; The name "convert_wareki_eto" says "convert": a word for a change.
Description, as the server wrote it 西暦の年（1926〜2080）を和暦（改元の年は両方）・十干十二支・年の九星に、または日付を和暦・本命星・月命星に換算する。year か date のどちらかを指定。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
Only reads 12Show 12 read-only tools
count_days2 つの日付の間の日数（開始日・終了日を含めるか選べる）と営業日数（土日祝を除く。定休の曜日・お盆・年末年始・個別の休業日と営業日も指定できる）。数え方は /tools/date-calculator と同じ。ある月の営業日の数は、その月の 1 日〜末日を start・end にして business_count_start: true で数える（既定の f…No findings
Why it is in this group
- The name "count_days" says "count": a word for reading.
Description, as the server wrote it 2 つの日付の間の日数（開始日・終了日を含めるか選べる）と営業日数（土日祝を除く。定休の曜日・お盆・年末年始・個別の休業日と営業日も指定できる）。数え方は /tools/date-calculator と同じ。ある月の営業日の数は、その月の 1 日〜末日を start・end にして business_count_start: true で数える（既定の false は開始日を数えない）。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
find_dates期間（366日まで）の中から、条件に合う日を探す。条件は六曜・吉日（一粒万倍日・天赦日・不成就日 など）・曜日・祝日・土日祝・二十四節気/雑節・新月/満月など・日干支（十干・十二支）。all（すべて）・any（どれか）・none（除く）で組み合わせ、offset_days で「翌日が満月」「前日が祝日」のようなずれも指定できる。例: 2027年の大安の土日で…No findings
Why it is in this group
- The name "find_dates" says "find": a word for reading.
Description, as the server wrote it 期間（366日まで）の中から、条件に合う日を探す。条件は六曜・吉日（一粒万倍日・天赦日・不成就日 など）・曜日・祝日・土日祝・二十四節気/雑節・新月/満月など・日干支（十干・十二支）。all（すべて）・any（どれか）・none（除く）で組み合わせ、offset_days で「翌日が満月」「前日が祝日」のようなずれも指定できる。例: 2027年の大安の土日で不成就日でない日。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
get_koyomi_day指定した日の暦: 和暦・旧暦（閏月）・六曜・吉日・不成就日・二十四節気/雑節・日干支・月齢と朔弦望の時刻・祝日・月食・年と月の九星。国立天文台・内閣府の公表値と照合したデータ（1926〜2080年）。No findings
Why it is in this group
- The name "get_koyomi_day" says "get": a word for reading.
Description, as the server wrote it 指定した日の暦: 和暦・旧暦（閏月）・六曜・吉日・不成就日・二十四節気/雑節・日干支・月齢と朔弦望の時刻・祝日・月食・年と月の九星。国立天文台・内閣府の公表値と照合したデータ（1926〜2080年）。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
get_koyomi_entity名前（例: 春分の日・土用の丑の日・十五夜・一粒万倍日・戌の日・不成就日・節分・彼岸）から、その年の日付・次はいつ・あと何日・定義・根拠を返す。二十四節気・雑節の名前（例: 秋分・春分・二百十日・春の彼岸入り）でも引ける。year を指定するとその年、from_date（省略時は今日）を指定すると次の日。No findings
Why it is in this group
- The name "get_koyomi_entity" says "get": a word for reading.
Description, as the server wrote it 名前（例: 春分の日・土用の丑の日・十五夜・一粒万倍日・戌の日・不成就日・節分・彼岸）から、その年の日付・次はいつ・あと何日・定義・根拠を返す。二十四節気・雑節の名前（例: 秋分・春分・二百十日・春の彼岸入り）でも引ける。year を指定するとその年、from_date（省略時は今日）を指定すると次の日。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
get_moon_events月食（皆既・部分・半影、日本での見え方と時刻）とスーパームーンの一覧。year（1926〜2080）か、start と end（366日まで）で指定。No findings
Why it is in this group
- The name "get_moon_events" says "get": a word for reading.
Description, as the server wrote it 月食（皆既・部分・半影、日本での見え方と時刻）とスーパームーンの一覧。year（1926〜2080）か、start と end（366日まで）で指定。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
get_moon_phases朔（新月）・上弦・望（満月）・下弦の瞬間（日本標準時・秒まで）の一覧。year（1926〜2080）か、start と end（366日まで）で指定。国立天文台の暦要項と照合済み。No findings
Why it is in this group
- The name "get_moon_phases" says "get": a word for reading.
Description, as the server wrote it 朔（新月）・上弦・望（満月）・下弦の瞬間（日本標準時・秒まで）の一覧。year（1926〜2080）か、start と end（366日まで）で指定。国立天文台の暦要項と照合済み。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
get_old_time日本時間の日時から、その日の明六つ・暮六つ（国立天文台の定義）と、不定時法の刻（暮六つ・暁九つ など）、十二辰刻（丑三つ時 など）を返す。地点は都道府県（省略時は東京都）。No findings
Why it is in this group
- The name "get_old_time" says "get": a word for reading.
Description, as the server wrote it 日本時間の日時から、その日の明六つ・暮六つ（国立天文台の定義）と、不定時法の刻（暮六つ・暁九つ など）、十二辰刻（丑三つ時 など）を返す。地点は都道府県（省略時は東京都）。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
get_rokuyo_hours指定した日の六曜と、時間帯ごとの吉凶（例: 先勝は午前が吉、赤口は正午前後だけ吉）。暦注の慣行による。No findings
Why it is in this group
- The name "get_rokuyo_hours" says "get": a word for reading.
Description, as the server wrote it 指定した日の六曜と、時間帯ごとの吉凶（例: 先勝は午前が吉、赤口は正午前後だけ吉）。暦注の慣行による。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
get_solar_term_times二十四節気の節入りの日時（日本標準時。秒までと、分に四捨五入した値）。立春・春分・夏至・秋分・冬至などが何時何分か。year（1926〜2080）か、start と end（366日まで）で指定。国立天文台 暦要項と照合済み。No findings
Why it is in this group
- The name "get_solar_term_times" says "get": a word for reading.
Description, as the server wrote it 二十四節気の節入りの日時（日本標準時。秒までと、分に四捨五入した値）。立春・春分・夏至・秋分・冬至などが何時何分か。year（1926〜2080）か、start と end（366日まで）で指定。国立天文台 暦要項と照合済み。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
get_sun_moon_times日の出・日の入り・月の出・月の入り・南中の時刻。指定した日・都道府県（47都道府県の代表地点）の日の出・南中・日の入りと、月の出・南中・月の入り（日本時間）。国立天文台「各地のこよみ」と同じ定義。No findings
Why it is in this group
- The name "get_sun_moon_times" says "get": a word for reading.
Description, as the server wrote it 日の出・日の入り・月の出・月の入り・南中の時刻。指定した日・都道府県（47都道府県の代表地点）の日の出・南中・日の入りと、月の出・南中・月の入り（日本時間）。国立天文台「各地のこよみ」と同じ定義。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
list_holidays国民の祝日・振替休日・国民の休日の一覧（内閣府の公表値と照合済み）。year（1926〜2080）か、start と end（366日まで）で指定。No findings
Why it is in this group
- The name "list_holidays" says "list": a word for reading.
Description, as the server wrote it 国民の祝日・振替休日・国民の休日の一覧（内閣府の公表値と照合済み）。year（1926〜2080）か、start と end（366日まで）で指定。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
search_lucky_days期間（366日まで）の中から、六曜（大安・友引など）と吉日（一粒万倍日・天赦日・寅の日など）の条件に合う日を探す。曜日で絞る・不成就日を除くこともできる。結果は200件まで。No findings
Why it is in this group
- The name "search_lucky_days" says "search": a word for reading.
Description, as the server wrote it 期間（366日まで）の中から、六曜（大安・友引など）と吉日（一粒万倍日・天赦日・寅の日など）の条件に合う日を探す。曜日で絞る・不成就日を除くこともできる。結果は200件まで。
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.
Exfil surface
Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.
No private-data, untrusted-input, outbound path in this server alone: no tool is tagged private-data or untrusted-input or outbound.
- Reads private data0
- Reads files, mail, messages, databases, secrets, calendars or repositories.
- Reads text others write0
- Brings in text someone else can write: web pages, inbound email, messages, issues and comments.
- Can send data out0
- Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.
Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.
Findings
Matches of fixed checks, with the text they matched.
The server marks "convert_wareki_eto" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
What this check looks forMatched text
annotations: {"readOnlyHint":true,"openWorldHint":false}; The name "convert_wareki_eto" says "convert": a word for a change.
- Warnadd_days
The server marks "add_days" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
What this check looks forMatched text
annotations: {"readOnlyHint":true,"openWorldHint":false}; The name "add_days" says "add": a word for a change.
History
Changes to its tool definitions and to its remote endpoint, newest first.
No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.
Install
Pinned to version 1.0.0. Values in angle brackets are yours to fill in.
claude mcp add --transport http koyomi https://bestcalendar.jp/mcpclaude mcp add --transport http koyomi https://bestcalendar.jp/mcpRun in a terminal.
Claude Code permissions
Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.
{
"permissions": {
"allow": [
"mcp__koyomi__get_koyomi_day",
"mcp__koyomi__search_lucky_days",
"mcp__koyomi__get_sun_moon_times",
"mcp__koyomi__list_holidays",
"mcp__koyomi__get_solar_term_times",
"mcp__koyomi__get_moon_phases",
"mcp__koyomi__get_koyomi_entity",
"mcp__koyomi__get_moon_events",
"mcp__koyomi__get_rokuyo_hours",
"mcp__koyomi__get_old_time",
"mcp__koyomi__count_days",
"mcp__koyomi__find_dates"
],
"ask": [
"mcp__koyomi__convert_wareki_eto",
"mcp__koyomi__add_days",
"mcp__koyomi__check_business_day",
"mcp__koyomi__answer"
],
"deny": []
}
}Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as koyomi. Review it before you use it.
Pin
Keep the decision: fail CI when the tools change, follow every change, or show a badge.
Pin in CI
Fail a build when the tools you reviewed are not the tools the server serves today.
curl -s "https://anlyon.dev/api/v1/servers/jp.bestcalendar/koyomi/verify?hash=af866e24e76acaec284a8a3f5cf4fae4227112676dcbac7daa468a7463c36996" | jq -e '.changed == false'Pinned hash af866e24e76a, from Oct 25, 2026, 14:26 UTC.
Watch
Get told when its tools change: a new tool, a new description, a new class.
https://anlyon.dev/servers/jp.bestcalendar/koyomi/changes.xmlAn Atom feed. Works in any feed reader or Slack's RSS app.
Badge
[](https://anlyon.dev/servers/jp.bestcalendar/koyomi)Source: MCP Registry. Synced Oct 25, 2026, 14:25 UTC.