jp-egov-law: Japanese laws for Hermes Agent, built on the e-Gov Law API

Ask your Hermes agent about Japanese law and get the official text of the article, with its law number, the date the current version took effect, and a link to the source, instead of a paraphrase from memory.

The data comes from the API of e-Gov 法令検索, the law database run by the Digital Agency of Japan (デジタル庁). No API key, no account, read-only.

日本語の要約：エージェントに「労基法32条」「民法第四百十五条」「個人情報保護法の次の改正はいつ？」と聞くと、 e-Gov の公式な条文・法令番号・施行日・出典を返します。導入はコマンド1行、APIキー不要。 改正は施行予定日と改正法の名前まで返し、条文が変わるかは同じ道具で1回で確かめられます。詳しくは 日本語の節。

What you can ask

You are...	You ask	What the agent does
Writing work rules (就業規則)	「労基法の法定労働時間（32条）の条文を出して」	One egov_law_article call: 労働基準法 第三十二条, both paragraphs, with the law number and the date the current version took effect
Reviewing a contract	「民法第四百十五条の条文を見せて」	One egov_law_article call: 第四百十五条（債務不履行による損害賠償）with its numbered items
Checking an amendment	「個人情報保護法の次の改正はいつ施行？」	One egov_law_revisions call: next_amendment (the soonest scheduled change), every scheduled change with its date and amending law, and the version in force now
Asking by topic	「年次有給休暇の付与日数を定めている条文は？」	The agent knows the topic lives in 労基法39条: one egov_law_article call, whose text_notes points to the 附則 articles that read 第三十九条 differently; the agent read them too. When it does not know the article, egov_law_search with mode="text" finds the laws that mention the phrase first
Using a vague name	「公務員の育休の法律の第2条を見せて」	The first call returns ambiguous_law with candidate law IDs; the agent reads 第2条 of both the 国家公務員 and the 地方公務員 law
Reviewing work rules for changes	「労基法で、次に施行される改正はある？」	One egov_law_revisions call: the next amendment and its date; each row's check pair then shows whether a given article changes
Checking one article against an amendment	「労基法115条は2027年4月の改正で変わる？」	One egov_law_article call with as_of (the day before) and compare_with (the day): changed or not, the line diff and the new wording. text_notes also points to 附則第143条, which keeps wage claims at three years for the time being; the same tool reads it

examples/scenarios.md records these requests run end to end: a separate model saw only what Hermes shows it, chose the calls, and wrote the final answers; every call went through Hermes's own dispatcher against the live API. Five of the eight needed one tool call (plus a tool_describe in S1); the topic question read two 附則 articles the result pointed to, the vague name needed one call for the candidates and one per law, and the amendment check also read 附則第143条.

Install

hermes plugins install TakeshiTGAL/hermes-plugin-egov-law --enable
hermes chat -Q -q "労働基準法第32条の条文を見せて"

The first line installs and enables the plugin (nothing else to install: standard library only). The second asks one question with the model you already configured in Hermes; the answer should quote 第三十二条 and cite e-Gov.

• Needs Hermes v0.21.4 or later (hermes --version); on an older one, run hermes update first.
• Installed without --enable? Run hermes plugins enable jp-egov-law.
• Using the messaging gateway? Run hermes gateway restart once.
• Installing from a local clone instead of GitHub: the directory must be a git clone. Run hermes plugins install file:///path/to/hermes-plugin-egov-law --enable; Hermes warns "Using insecure/local URL scheme" and installs it.
• Once the plugin is in the Hermes catalog: hermes plugins install jp-egov-law --enable.
• Checked against Hermes main at commit 0a374d16 (2026-10-02): hermes plugins validate passes, and the plugin installs, enables and answers through Hermes's own tool dispatcher.

Hermes lists plugin tools behind its tool search, so the model sees a one-line entry per tool (for example egov_law_article: Japanese law article: law='労基法', article='32' or '三十二条の二'.) and loads the full schema when it needs it. No configuration is required.

Tools

Tool	Use it when	Main arguments
egov_law_article	The user names a law and an article, or you need the wording of a provision, or whether an amendment changes it	law, article, optional paragraph, as_of, compare_with, max_chars
egov_law_search	You do not know the exact law, need its number or ID, or want laws that mention a phrase	query, mode (title or text), limit, include_repealed
egov_law_revisions	The question is about when something took or takes effect, or upcoming amendments	law, limit

Ways to name a law (law)

• Official title: 労働基準法, 個人情報の保護に関する法律
• e-Gov abbreviation: 労基法, 個人情報保護法, 安衛法, 労契法
• Common short names e-Gov does not index, built in: 個情法, 特商法, 下請法, 雇保法, 育介法, 育児休業法, 電帳法, パート法, フリーランス法, 派遣法, 均等法, 憲法, 健保法, 厚年法, パワハラ防止法, 高年法, 労基則, 雇保則
• Law number, kanji or digits: 昭和二十二年法律第四十九号, 昭和22年法律第49号
• e-Gov law ID: 322AC0000000049

If a partial name matches several laws (労働), the tool returns an error that lists the candidates with their law IDs, so the agent can pick one and call again.

Ways to write an article (article)

第32条, 32条, 32, 三十二条, 第三十二条, 第３２条, Article 32. Branch articles: 第三十二条の二, 32の2, 32-2. With a paragraph: 第32条第2項 (or paragraph: 2). The law's own 附則: 附則第143条, or 附則 for one without articles. Items (号), 本文 and ただし書 cannot be selected: 第32条第1項第2号 returns paragraph 1 with a note.

What comes back

egov_law_article for {"law": "労基法", "article": "三十二条"} (shortened; data as of 2026-10-02):

{
  "law_title": "労働基準法",
  "law_num": "昭和二十二年法律第四十九号",
  "law_id": "322AC0000000049",
  "article": "第三十二条",
  "caption": "（労働時間）",
  "text": "（労働時間）\n第三十二条　使用者は、労働者に、休憩時間を除き一週間について四十時間を超えて、労働させてはならない。\n２　使用者は、一週間の各日については、労働者に、休憩時間を除き一日について八時間を超えて、労働させてはならない。",
  "paragraphs": 2,
  "law_version": {"note": "Version of the whole law. This article did not necessarily change in it.", "in_force_since": "2026-07-17", "status": "in force now", "last_amended_by": "労働者災害補償保険法等の一部を改正する法律（令和八年法律第六十号）"},
  "url": "https://laws.e-gov.go.jp/law/322AC0000000049",
  "source": {"attribution": "出典：e-Gov法令検索（https://laws.e-gov.go.jp/）のデータを hermes-plugin-egov-law が取得・整形（条単位の抽出等）", "retrieved_on": "2026-10-02"}
}

Long articles are cut at max_chars (default 4,000 characters), at a line break when one falls in the second half of the budget and mid-line otherwise. Nothing is added to the text. The result is marked "truncated": true with total_chars, and next_step says which max_chars (up to 20,000) gets the rest. as_of: "2018-01-01" returns the wording in force on that date (e-Gov keeps versions from 2017-04-01), and a future date returns the text as a scheduled amendment will make it read. url always opens the law's current version on e-Gov, even when you asked for another date.

compare_with adds a comparison in the same call: changed (true or false), a diff of whole paragraph and item lines (- the text on as_of, + the text on compare_with) and the wording on compare_with. The diff is also kept within max_chars. To see what one amendment does to an article, use the check pair that egov_law_revisions gives each amendment: as_of = the day before it takes effect, compare_with = the day. Amendments taking effect on the same day cannot be told apart.

When an article of the law's own 附則 says how the article applies (「第百十五条の規定の適用については…」), text_notes names that 附則 article. Some of these transitional rules still apply and some have expired; the note does not tell which.

When something goes wrong

Tools never raise. Every failure is a JSON object with error, error_type and a next_step that tells the agent what to do:

error_type	Example	next_step says
article_not_found	労働基準法 第九九九九条	do not guess nearby numbers; it may be deleted or only added by an upcoming amendment; the e-Gov page. If the article was in the version just before the current one, see Limitations
paragraph_not_found	第三十六条 with paragraph: 99	how many paragraphs the article has
not_covered	別表第一, 様式	do not retry; give the user the e-Gov page (its URL is in next_step)
law_not_found	a law name that matches nothing	search with a shorter name or mode="text"
ambiguous_law	労働	pick one of the listed law IDs, or search with a longer name
bad_argument	as_of: "2000-01-01"	use a date on or after 2017-04-01
timeout / network	e-Gov unreachable	wait and retry, at most twice / check the connection
upstream / bad_response	e-Gov maintenance	try again later
not_found / bad_request	e-Gov rejected a lookup	its message, and to check the law with egov_law_search / fix the argument
too_large	a response over 8 MB	ask for one article
internal	an unexpected error in the plugin	retry once, then give the user the e-Gov page

A search with no hits is not an error: it returns "total_matches": 0 with a message and a next step.

Network, data and privacy

• One host. The plugin sends HTTPS GET requests to https://laws.e-gov.go.jp/api/2 and nowhere else. The request contains what the agent looks up (a law name, article number or search phrase). Redirects are followed only to https://laws.e-gov.go.jp; one to another host or to plain HTTP is refused.
• No credentials. The API is public; the plugin reads no environment variables and stores no keys. (Python's urllib still uses the system proxy settings such as HTTPS_PROXY.)
• Nothing written. No files, no database, no telemetry. Name-to-law-ID answers and the law's own 附則 articles read for text_notes are kept in process memory (at most 256 entries together, oldest dropped first) and disappear when Hermes exits.
• Never waits for input. No prompts. A tool call makes one to six requests (name lookup, the text, the 附則 check, a comparison, error details such as the previous version of a missing article), at most one per second from the process, each with a 15-second socket timeout and an 8 MB response cap. Even when e-Gov hangs, a call ends with an error in about a minute and a half, so cron jobs and the gateway are not stuck.
• Gentle on e-Gov. The one-request-per-second pace is built in; e-Gov is a public service.
• No self-updates, no shell commands, no background processes.

Source and attribution

Law data is published by the Digital Agency of Japan on e-Gov. The terms of use of e-gov.go.jp and its subdomains (利用規約, checked 2026-10-02) apply the Public Data License 1.0 (公共データ利用規約 第1.0版) and ask users to:

1. show the source, e.g. 出典：e-Gov法令検索（https://laws.e-gov.go.jp/）, and
2. when content is edited or processed, say so and who did it, without presenting the result as the government's unedited original.

Every successful tool result carries source.attribution (出典：e-Gov法令検索（https://laws.e-gov.go.jp/）のデータを hermes-plugin-egov-law が取得・整形（条単位の抽出等）) and retrieved_on; the egov_law_article description and the source.note in every result ask the model to show it with any law text it quotes. The plugin retrieves law text; it does not give legal advice.

Limitations

• egov_law_article reads the main provisions (本則) and the law's own supplementary provisions (附則), including articles later inserted into them such as 労基法 附則第143条. The separate 附則 that each amending law carries (where many transitional measures of later reforms live), appended tables (別表) and forms are not returned. Where e-Gov holds only an excerpt (抄) of a 附則, text_notes says so.
• Articles deleted as a range (第十条から第十二条まで　削除) cannot be fetched one by one.
• An article renumbered or deleted by an amendment is article_not_found under its old number, and the tool does not give the new number. When as_of is left out, the tool looks once at the version in force the day before the current version took effect. If the article is there, the error says so: the date it last existed, the date and the amending law (title and number) of the amendment that moved or deleted it, the old caption (previous_caption), and a next_step to search for the caption's words with mode="text" or check the e-Gov page. Example: 労働施策総合推進法 (パワハラ防止法) 第三十条の二, moved or deleted by the amendment that took effect on 2026-10-01. An article that went in an earlier amendment gets the plain error; reading it with as_of before that amendment still works.
• mode="text" snippets come without article numbers; use them to find the law, then read the article.
• Tables inside an article are flattened to one line per row with ｜ between cells, and the result says so in text_notes (outside the law text). Tables with multi-row headers do not line up column by column.
• In revisions, title_names_this_law only says whether the amending law's title names this law (as a word of its own, current or former title), and follow_up_of only names X in a title 「〈X〉の施行に伴う…」. Neither says how much the law changes: a reform titled after another law can change this one a lot.
• Revisions say when and by which law a law changes, not which articles change. Check an article with the row's check pair (changed or not, and the diff, in one call). Each row also says change: an amendment, a repeal (scheduled_repeal at the top), or the law's own provisions taking effect. For a law whose repeal has taken effect, in_force_now is empty and repealed_on, the message and next_step say so, with as_of = the day before the repeal for reading its last wording.
• For a scheduled amendment whose date the law leaves to a cabinet order (date_fixed: false, see enforcement_note), e-Gov shows a provisional date; for 「…を超えない範囲内において政令で定める日」 it is the latest possible day, so the change may come earlier than amendments listed before it.
• e-Gov labels the JSON form of its law-text API as a trial (試行版). If e-Gov changes it, the plugin returns an error rather than wrong text, and the fix is a new release.
• When e-Gov marks no version as current (it happens for a while after a new version takes effect), egov_law_revisions picks the newest version whose enforcement date has passed.

Development

Test dependencies: pytest 8 and PyYAML 6.

pytest -q                    # offline tests + live tests (about 35 paced requests to e-Gov)
pytest -q -m "not live"      # offline only (recorded responses in tests/fixtures)
python tests/record_fixtures.py   # re-record the responses the offline tests replay
hermes plugins validate . --install-deps   # the check the Hermes plugin catalog runs

Python 3.11+ (what Hermes requires). No runtime dependencies.

日本語

e-Gov 法令 API（v2）を活用して、Hermes Agent から日本の法令を引けるようにしたプラグインです。 データはデジタル庁の e-Gov 法令検索から取り、APIキーもアカウントも要りません。

• 条文を読む（egov_law_article）：「労基法32条」「民法第四百十五条」「個人情報保護法 第二十七条」のように、 法令名・略称・法令番号と条番号を渡します。条番号は 第32条／32条／三十二条／32の2 のどれでも通り、1回で条文が返ります。 法律本体の附則（後から足された附則第143条なども含む）も「附則第143条」の形で読めます。改正法それぞれの附則は読めません。 経過措置の附則がその条を当分の間読み替えているときは、text_notes がその附則の条を示します。
• 改正で条文が変わるか確かめる：egov_law_article に as_of（施行日の前日）と compare_with（施行日）を付けると、差分が同じ1回で返ります。 この2つの日付は egov_law_revisions の各改正の check に入っています。
• 法令を探す（egov_law_search）：法令名・略称で探します（既定）。mode="text" にすると本文の語句から探します。
• 改正と施行日を確かめる（egov_law_revisions）：いま施行中の版、施行予定の改正と日付、過去の版を返します。 next_amendment は最も近い予定の改正です。title_names_this_law は改正法の題名にこの法律の名前があるか、 follow_up_of は「〈X〉の施行に伴う…」という題名の X です。どちらも中身がどれだけ変わるかは表しません。 条文が変わるかは check の日付で確かめてください。廃止の予定は scheduled_repeal に出ます。 すでに廃止された法律は in_force_now が空になり、repealed_on と、最後の文言を読むための as_of（廃止日の前日）を返します。

導入1行、動作確認1行です。

hermes plugins install TakeshiTGAL/hermes-plugin-egov-law --enable
hermes chat -Q -q "労働基準法第32条の条文を見せて"

略称は e-Gov の略称（労基法・個人情報保護法・安衛法など）に加え、個情法・特商法・下請法・雇保法・育介法・育児休業法・ パート法・フリーランス法・派遣法・均等法・憲法・健保法・厚年法・電帳法・パワハラ防止法・高年法・労基則・雇保則を組み込んでいます。

Hermes は v0.21.4 以上が必要です（hermes --version で確認）。古い場合は先に hermes update を打ってください。 --enable を付け忘れたら hermes plugins enable jp-egov-law を打ってください。 GitHub ではなく手元から入れる場合は、git clone したディレクトリを hermes plugins install file:///path/to/hermes-plugin-egov-law --enable で指定します（「Using insecure/local URL scheme」という警告が出ますが、導入されます）。 メッセージ連携（gateway）を使っている場合は、hermes gateway restart を一度打ってください。

通信先は https://laws.e-gov.go.jp/api/2 だけで、e-Gov 以外へは何も送りません。ファイルも書きません。 1回のツール呼び出しで e-Gov への問い合わせは1〜6回、1秒に1回までに抑えています。1回ごとに通信が15秒止まれば打ち切るので、 e-Gov が止まっていても入力待ちにはならず、1分半ほどでエラーが返ります。 返り値には出典表示 出典：e-Gov法令検索（https://laws.e-gov.go.jp/）のデータを hermes-plugin-egov-law が取得・整形（条単位の抽出等） が入ります。e-Gov の利用規約（公共データ利用規約 第1.0版）に沿って、条文を見せるときはこの出典も一緒に示してください。

できないこと：

• 改正法それぞれの附則・別表・様式は返しません（別表・様式は not_covered のエラーで e-Gov のページを案内します）。
• 号・本文・ただし書だけを取り出すことはできません（項までを返し、注記を付けます）。範囲で削除された条は1条ずつ取れません。
• 本文検索（mode="text"）の抜粋には条番号が付きません。過去の版は 2017-04-01 以降だけです。
• 施行日を政令に任せた改正（date_fixed: false）は、e-Gov の仮の日付です。「…を超えない範囲内」の場合は最も遅い日です。
• 改正で番号が変わった条や削除された条は、旧い番号では article_not_found になり、新しい番号は返しません。 as_of を付けないときは、現行版の施行日の前日の版を1回だけ確かめます。そこに条があれば、いつまであったか・どの改正（施行日と改正法の題名・番号）で動いたか・旧い見出し（previous_caption）をエラーに入れ、見出しの語で mode="text" 検索するか e-Gov のページで確かめるよう案内します。
• 条文中の表は1行ずつ「｜」区切りに平らにします。e-Gov の本文取得 API は試行版の扱いです。 本プラグインは条文を取り出す道具で、法的助言はしません。

License

MIT. See LICENSE. Law data: e-Gov 法令検索, Digital Agency of Japan, under PDL 1.0.