@codeagentjp/houan-mcp

Local stdio MCP server for searching Japanese Diet bills (衆参議案情報) and committee Q&A records via the NDL Kokkai (国会会議録検索システム) API.

This server does not call an LLM. It only returns source-backed Diet data, with primary URLs (NDL Kokkai, 衆議院議案情報, 参議院議案情報) so your MCP client (Claude Desktop, Claude Code, Cursor, or any other agent) can cite the original source.

Sister package: @codeagentjp/egov-law-mcp for current Japanese laws (e-Gov Law Search). houan-mcp covers the legislative process side: bills under deliberation, committee questionings, and full meeting transcripts.

Status

MVP. Four tools:

• find_diet_qa — full-text search across all Diet committee speeches via the NDL Kokkai API. Filter by date, chamber, committee, speaker.
• get_meeting_record — retrieve a single committee's full transcript by issueID.
• search_bills — search current-session bills in either house by title keyword.
• get_bill — retrieve detail of one bill (proceedings timeline, committee assignment, full-text URL).

Requirements

• Node.js 20 or later
• Network access to https://kokkai.ndl.go.jp, https://www.shugiin.go.jp, https://www.sangiin.go.jp

Install

From npm:

{
  "mcpServers": {
    "houan": {
      "command": "npx",
      "args": ["-y", "@codeagentjp/houan-mcp"]
    }
  }
}

From source:

git clone https://github.com/SHAYOUWORLD/houan-mcp.git
cd houan-mcp
node bin/houan-mcp.mjs

{
  "mcpServers": {
    "houan": {
      "command": "node",
      "args": ["/absolute/path/to/houan-mcp/bin/houan-mcp.mjs"]
    }
  }
}

Tools

find_diet_qa

Full-text search of Diet committee speeches via the NDL Kokkai API.

{
  "keyword": "クロード ミトス",
  "from": "2026-04-01",
  "until": "2026-04-25",
  "chamber": "衆議院",
  "committee": "外務委員会",
  "limit": 5
}

Returns matched speeches with speaker, position, committee context, and direct NDL URL.

get_meeting_record

Retrieve a single full transcript by issueID.

{
  "issueID": "122103968X00620260410"
}

search_bills

Search 衆議院議案情報 / 参議院議案情報 by title keyword.

{
  "keyword": "情報",
  "chamber": "both",
  "session": 222,
  "limit": 20
}

When session is omitted, the server reads the session list behind the 衆議院議案情報 dropdown (.../html/gian/pulldown.htm, one small request, cached for 5 minutes like other responses) and searches the highest session listed, for both chambers. If that list cannot be read, it searches 222 (checked 2026-10-28) and adds an entry to warnings. query.sessionSource is latest, fallback, or argument. Specify session explicitly for historical sessions; no session list is fetched then.

For Shugiin results, session is the searched session, submittedSession is the session in which the item was introduced, and billType distinguishes 衆法 / 参法 / 閣法 and other agenda items. billNumber is the official number (or null for unnumbered items); status comes from 審議状況. Unpublished proceedings/full-text links are null.

HTTP, network, timeout, and unrecognized Shugiin table errors are returned as an MCP tool result with isError: true. Its text contains error, sourceErrors (chamber, URL, message) and warnings, rather than a successful zero-hit result. When searching both, a failure in either chamber fails the whole search; request one chamber explicitly if you want to retry it alone. A successful search with no title matches still returns matched: 0 and results: [].

get_bill

Retrieve a bill detail page (proceedings timeline, committee assignment, full-text URL). The proceedingURL must be a URL returned by search_bills — it is validated against the chamber's allowed path prefix before fetching.

{
  "chamber": "shugiin",
  "proceedingURL": "https://www.shugiin.go.jp/internet/itdb_gian.nsf/html/gian/keika/1D

... [View full README on GitHub](https://github.com/shayouworld/houan-mcp#readme)