Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
git clone --depth 1 https://github.com/koizumikento/reinfolib-mcpWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/rules/koizumikento/reinfolib-mcp/api-development)<a href="https://agentmods.dev/rules/koizumikento/reinfolib-mcp/api-development"><img src="https://agentmods.dev/badge/rules/koizumikento/reinfolib-mcp/api-development/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/rules/koizumikento/reinfolib-mcp/api-development"><img src="https://agentmods.dev/badge/rules/koizumikento/reinfolib-mcp/api-development.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00000 | $0.00677 |
| Opus 5.5 | $0.00000 | $0.00271 |
| Sonnet 5.5 | $0.00000 | $0.00135 |
| Haiku 4.5 | $0.00000 | $0.00068 |
Grade A, and why
api-development scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
不動産情報ライブラリAPI開発規則
APIクライアント開発ガイドライン
1. HTTPSリクエスト処理
- 全てのAPIリクエストはHTTPSプロトコルを使用
- APIキーはHTTPヘッダー
Ocp-Apim-Subscription-Keyで送信 - リクエストタイムアウトとリトライ機能を実装
2. レスポンス形式対応
# サポートする出力形式
SUPPORTED_FORMATS = {
'json': 'application/json',
'geojson': 'application/geo+json',
'pbf': 'application/x-protobuf' # バイナリベクトルタイル
}
3. エラーハンドリング
- APIキー未設定エラー
- レート制限エラー
- データ形式エラー
- ネットワークエラー
4. データモデル定義
- Pydanticを使用したタイプセーフなデータモデル
- GeoJSONオブジェクトの適切な型定義
- 日本語フィールド名の英語マッピング
5. APIクライアントラッパー設計
# ラッパークラスを使用した設計
from reinfolib_mcp import ReinfiolibClient
# APIキー直接指定
client = ReinfiolibClient(api_key="your_api_key")
# 環境変数から自動取得
client = ReinfiolibClient() # REINFOLIB_API_KEY環境変数を使用
6. API URL パターン
BASE_URL = "https://www.reinfolib.mlit.go.jp/ex-api/external"
# APIエンドポイント例
ENDPOINTS = {
"real_estate_price": "/XIT001", # 不動産価格情報
"municipalities": "/XIT002", # 市区町村一覧
"appraisal_info": "/XIT003", # 鑑定評価書情報
# ... 他のエンドポイント
}
7. 地理空間データ処理
- GeoJSONオブジェクトの適切な処理
- 座標系の変換対応（JGD2011等）
- バイナリベクトルタイルのデコード
8. ユニットテスト
- モックレスポンスを使用したテスト
- 全APIエンドポイントのテストカバレッジ
- エラーケースのテスト
9. 非同期処理
- asyncio/aiohttpを使用した非同期APIクライアント
- 複数APIの並行呼び出し対応
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2mo ago First seen · 85 lines · 677 tokens per session scan A 8f0ad81ebc44
api-development is a cursor rule published in the GitHub repository koizumikento/reinfolib-mcp (2 stars, last pushed 2mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 677 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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