jp.ossalt/jp-biz-tools

What it mainly works on, as our AI model read its tool descriptions: nothing outside itself: it only answers questions.

None of its 13 tools are described as changing anything.

• list_holidayson 10 other serversreads or searches

  “List all Japanese national holidays and substitute holidays for a year, based on the National Holidays Act and verified against the Cabinet Office CSV.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  1 input, 1 required

  • yearintegerrequired“Year (1980-2099) / 年”
• check_business_dayon 2 other serversreads or searches

  “Check whether a date is a business day in Japan, and if not, why (weekend, holiday name, bank closure, or a custom closed day).”

  Publisher declares: read-only yes · idempotent yes · open-world no

  4 inputs, 1 required

  • datestringrequired“Date (YYYY-MM-DD) / 日付”
  • calendarstring“"standard": weekends and national holidays are closed.”
  • extra_holidaysarray“Additional company-specific closed days (e.g.”
  • extra_business_daysarray“Days treated as business days even if they are weekends or holidays.”
• add_business_dayson 22 other serverscalculates or converts

  “Return the date that is N business days after (or before, if N is negative) the given date.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  5 inputs, 2 required

  • datestringrequired“Start date (YYYY-MM-DD) / 起算日”
  • daysintegerrequired“Number of business days (negative = before) / 営業日の数（負なら前）”
  • calendarstring“"standard": weekends and national holidays are closed.”
  • extra_holidaysarray“Additional company-specific closed days (e.g.”
  • extra_business_daysarray“Days treated as business days even if they are weekends or holidays.”
• count_business_dayson 7 other servers

  “Count business days from start to end, inclusive of both ends.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  5 inputs, 2 required

  • startstringrequired“Start date (YYYY-MM-DD) / 開始日”
  • endstringrequired“End date (YYYY-MM-DD) / 終了日”
  • calendarstring“"standard": weekends and national holidays are closed.”
  • extra_holidaysarray“Additional company-specific closed days (e.g.”
  • extra_business_daysarray“Days treated as business days even if they are weekends or holidays.”
• adjust_to_business_daycalculates or converts

  “If the date is a business day, return it as is; otherwise move to the next ("next") or previous ("previous") business day.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  5 inputs, 1 required

  • datestringrequired“Date (YYYY-MM-DD) / 日付”
  • directionstring“next = 後ろ倒し, previous = 前倒し”
  • calendarstring“"standard": weekends and national holidays are closed.”
  • extra_holidaysarray“Additional company-specific closed days (e.g.”
  • extra_business_daysarray“Days treated as business days even if they are weekends or holidays.”
• last_business_day_of_monthcalculates or converts

  “Return the last business day of the given month.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  5 inputs, 2 required

  • yearintegerrequired“Year (1980-2099) / 年”
  • monthintegerrequired“Month (1-12) / 月”
  • calendarstring“"standard": weekends and national holidays are closed.”
  • extra_holidaysarray“Additional company-specific closed days (e.g.”
  • extra_business_daysarray“Days treated as business days even if they are weekends or holidays.”
• to_japanese_eracalculates or converts

  “Convert a Gregorian date (YYYY-MM-DD) to the Japanese era calendar, e.g.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  1 input, 1 required

  • datestringrequired“Date (YYYY-MM-DD) / 日付”
• from_japanese_eracalculates or converts

  “Convert a Japanese era date to YYYY-MM-DD.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  1 input, 1 required

  • warekistringrequired“Japanese era date, e.g.”
• lookup_postal_codeon 4 other serversreads or searches

  “Look up the address (prefecture, city, town) for a 7-digit Japanese postal code, from Japan Post data.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  1 input, 1 required

  • postal_codestringrequired“7-digit postal code, hyphen optional / 郵便番号（7桁、ハイフンは任意）”
• search_postal_codereads or searches

  “Find Japanese postal codes by prefecture, city and (optionally) part of the town name, from Japan Post data.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  4 inputs, 1 required

  • prefecturestring“Prefecture, e.g.”
  • citystringrequired“Municipality, e.g.”
  • townstring“Part of the town name, e.g.”
  • office_namestring“Part of a business name, in kanji or katakana (optional) / 事業所名の一部（任意）”
• normalize_addresscalculates or converts

  “Split a Japanese address into prefecture, city, town and the rest (block numbers, building), matching Japan Post's address data, and return candidate postal codes.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  1 input, 1 required

  • addressstringrequired“Japanese address, e.g.”
• lookup_corporate_numberon 2 other serversreads or searches

  “Look up a 13-digit Japanese corporate number (法人番号) in the National Tax Agency's monthly bulk data: name, furigana, English name, kind, registered address and postal code, assignment date, and closur…”

  Publisher declares: read-only yes · idempotent yes · open-world no

  1 input, 1 required

  • corporate_numberstringrequired“13-digit corporate number, hyphens/spaces allowed / 法人番号（13桁。ハイフン・空白は任意）”

Each quoted sentence is the first sentence of the publisher’s own description. The kind of tool and the “changes data” mark are our AI model’s reading of that description, not something we tested: two differently worded runs had to agree, otherwise no label is shown, and nobody has checked them by hand. A tool without the “changes data” mark is described as only reading, searching or calculating, or the two runs did not agree. No tool was called. Read the publisher’s full description before relying on it. “Publisher declares” lists the hints the server itself sends with the tool (MCP annotations: read-only, destructive, idempotent, open-world); they are the publisher's claims, not checked by us. Inputs are the parameters in the tool's own input schema: name, declared type, whether it is required, and the first sentence of its description. Read 2026-10-23.

The registry verifies a package once, when it is published, and does not re-check it. A difference below is about the listing, not a judgement of the publisher.