CanLII APIを介してカナダの法情報を検索するためのModel Context Protocol (MCP)サーバーです。Claude DesktopやClaude Codeから、判例の検索、法令の閲覧、引用確認が可能です。
npx canlii-mcp全文検索 — キーワード、事件名、または法的概念を使用してCanLII全体を検索
判例引用確認（シテーター） — 後続の判例でどのように引用されているかを確認し、その判例が現在も有効な法として機能しているかをチェック
法令閲覧 — 管轄区域ごとに制定法や規則を閲覧
バイリンガル — 引用確認ツールを含むすべてのツールで英語とフランス語をサポート
9つのツール — 検索、裁判所一覧、判例一覧、判例メタデータ、完全な引用確認、引用確認プレビュー、法令データベース、法令閲覧、法令メタデータ
組み込みのレート制限 — シリアル化されたリクエストキューにより、CanLIIのAPI制限（2リクエスト/秒、同時接続1、5,000リクエスト/日）を遵守
入力バリデーション — すべてのパラメータは正規表現で検証され、インジェクションを防ぐためにURIエンコード済み
最小限のフットプリント — 実行時依存関係は2つのみ、約500行のコード、stdioプロセスとしてローカルで動作
セキュリティ重視 — ファイルシステムへのアクセスやシェル実行は一切なく、api.canlii.orgへの接続のみを実行
Related MCP server: canlii-mcp
前提条件: Node.js 18以上およびCanLII APIキー（研究用途は無料）。
Claude Desktop — 設定ファイルに追加してください（macOSの場合は ~/Library/Application Support/Claude/claude_desktop_config.json）:
{
"mcpServers": {
"canlii": {
"command": "npx",
"args": ["-y", "canlii-mcp"],
"env": {
"CANLII_API_KEY": "your_api_key_here"
}
}
}
}保存後、Claude Desktopを再起動してください。
Claude Code:
claude mcp add canlii -e CANLII_API_KEY=your_key -- npx -y canlii-mcpソースから実行（開発用）:
git clone https://github.com/mohammadfarooqi/canlii-mcp.git
cd canlii-mcp
npm install && npm run buildCanLII全体（判例、法令、解説）に対する全文キーワード検索。法務リサーチの主要な入り口です。
search({ query: "material change in circumstances Ontario", resultCount: 10 })利用可能なすべての裁判所および審判所のデータベースを一覧表示します。他のツールで必要なデータベースIDを返します。
オンタリオ州の主要データベース: onsc（高等裁判所）、onca（控訴裁判所）、oncj（司法裁判所）、csc-scc（カナダ最高裁判所）。
特定の裁判所データベースから、最近追加された順に判例を閲覧します。日付フィルタをサポートしています。
get_case_law_decisions({ databaseId: "onsc", resultCount: 20 })特定の判例の詳細（引用、判決日、事件番号、キーワード、および全文を読むためのCanLII URL）を取得します。
get_case_metadata({ databaseId: "onsc", caseId: "2021onsc8582" })判例の引用関係を調べます。citingCasesを使用して、その判例が現在も有効な法として機能しているかを確認します。
get_case_citator({ databaseId: "csc-scc", caseId: "1996canlii190", metadataType: "citingCases" })最大5件の結果を返すクイック引用プレビュー。完全な引用確認よりも高速に確認できます。
get_case_citator_tease({ databaseId: "csc-scc", caseId: "1996canlii190", metadataType: "citingCases" })すべての法令データベースを一覧表示します。オンタリオ州: ons（制定法）、onr（規則）。連邦: cas（制定法）、car（規則）。
特定のデータベース内の法令項目を一覧表示します。
browse_legislation({ databaseId: "ons" })特定の制定法や規則のメタデータ（CanLII URLを含む）を取得します。
検索 — search({ query: "gatekeeping parenting time" }) で関連する判例を探す
詳細取得 — get_case_metadata(...) で完全な引用とCanLII URLを取得する
引用確認 — get_case_citator(..., metadataType: "citingCases") でその判例が現在も有効かを確認する
判決を読む — CanLII URLをクリックしてcanlii.orgで全文を読む
CanLIIのAPI利用規約に基づきます:
1日あたり5,000クエリ
1秒あたり2リクエスト
同時リクエストは1つまで
メタデータアクセスのみ — 文書全文はAPI経由では利用できません
サーバーは組み込みのレートリミッターにより、これらの制限を自動的に強制します。
npm run build # Compile TypeScript
npm run start # Run the server (needs CANLII_API_KEY env var)src/
index.ts # MCP server — tools, rate limiter, stdio transport
schema.ts # Zod schemas for CanLII API responses貢献を歓迎します！このプロジェクトは、AIツールを通じてカナダの法務リサーチをより身近にすることを目指しています。
貢献方法:
バグや予期しないAPI動作の報告 — Issueを開く
新しいツールや改善の提案 — ディスカッションを開始する
修正や新機能のPRを提出する
PRを提出するには:
このリポジトリをフォークする
フィーチャーブランチを作成する (git checkout -b feature/my-improvement)
変更を加えてローカルでテストする (npm run build && CANLII_API_KEY=your_key npm run start)
フォーク先にコミットしてプッシュする
何を変更したか、なぜ変更したかの説明を添えてプルリクエストを開く
CanLII APIのレスポンスやスキーマの不一致、あるいは法務リサーチに役立つ新しいツールのアイデアがあれば、修正方法がわからなくてもIssueを開いてください。一緒に調査しましょう。
このサーバーは透明性と最小限の構成を重視して設計されています:
api.canlii.orgへの接続のみ — 他のネットワーク呼び出し、テレメトリ、分析は一切なし
APIキーはローカルに保持 — 環境変数経由で渡され、ログやレスポンスに含まれることはない
すべての入力を検証 — データベースID、ケースID、日付は使用前に正規表現で検証され、パスセグメントはURIエンコードされる
すべてのAPIレスポンスを検証 — 返される前にZodスキーマで解析される
ファイルシステムへのアクセスなし — サーバーはCanLIIへのHTTPS呼び出しのみを行う
シェル実行なし — child_process、exec、spawnは使用しない
2つの実行時依存関係 — @modelcontextprotocol/sdk（公式Anthropic MCP SDK）とzod（スキーマ検証）
レートリミッター内蔵 — シリアル化されたリクエストキューがAPIの乱用を防ぐ
MITライセンス、完全オープンソース — src/index.ts（約350行）とsrc/schema.ts（約140行）のすべての行を確認可能
セキュリティ上の問題を発見した場合は、SECURITY.mdを参照してください。
判決文の本文なし — 全文検索は機能しますが（判例タイトル、引用、コンテンツ全体を検索）、APIは判決の全文を返すことができません。判決を読むにはCanLII URLをクリックしてcanlii.orgにアクセスする必要があります。段落番号や直接の引用は、ソースを読んで確認する必要があります。
検索はキーワードベースであり、意味論的ではない — 「mother gatekeeping sole decision-making」のようなクエリは混在した結果を返す可能性があります。クエリを絞り込み、メタデータを掘り下げる前に判例タイトルを確認してください。
検索結果に判例の詳細が含まれない — 検索結果は引用とタイトルのみを返します。キーワード、トピック、判決日、CanLII URLを取得するには、各判例に対して個別にget_case_metadataを呼び出す必要があります。
処理指標がない — 引用確認ツールはどの判例がその判決を引用しているかを示しますが、それが「支持された（followed）」のか、「区別された（distinguished）」のか、「覆された（overturned）」のかは示しません。処理内容を判断するには、引用している判例を読む必要があります。
引用確認プレビューは最大5件まで — 包括的な引用分析にはget_case_citator（完全版）を使用してください。
検索にデータベース/管轄区域のフィルタがない — サーバー側で特定の裁判所や州に検索結果を限定することはできません。代わりにクエリに管轄区域のキーワードを追加してください（例：「custody」ではなく「custody Ontario」）。
検索エンドポイントは非公式 — 機能しますがCanLIIの公式APIドキュメントには記載されていないため、予告なく変更される可能性があります。
レート制限が厳しい — 1日5,000クエリ、2リクエスト/秒、同時リクエスト1（組み込みのレートリミッターにより自動的に強制）。
MIT — LICENSEを参照してください。
List all legislation items in a specific database. Use to find legislation IDs for metadata lookup. Key statutes by database — ons: Children's Law Reform Act, Family Law Act, Employment Standards Act. cas: Divorce Act, Criminal Code, Canada Labour Code, Federal Child Support Guidelines.
| Name | Required | Description | Default |
|---|---|---|---|
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| databaseId | Yes | Legislation database ID (e.g., 'ons' for Ontario Statutes, 'cas' for Canada Statutes, 'onr' for Ontario Regulations) | |
| publishedBefore | No | Date first published on CanLII (YYYY-MM-DD) | |
| publishedAfter | No | Date first published on CanLII (YYYY-MM-DD) | |
| modifiedBefore | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| modifiedAfter | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| changedBefore | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| changedAfter | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| decisionDateBefore | No | Decision date upper bound (YYYY-MM-DD) | |
| decisionDateAfter | No | Decision date lower bound (YYYY-MM-DD) |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, and the description does not disclose behavioral traits such as pagination, rate limits, or output size. For a listing tool, this is a significant gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three focused sentences: purpose, use case, and examples. No redundant information; every sentence is necessary.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given 10 parameters and no output schema, the description is adequate but lacks details on how filters interact, output format, or pagination. Suitable for a basic list tool but not fully complete.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, but the description adds value by listing key statutes per database (e.g., 'ons: Children's Law Reform Act'), helping agents select the correct databaseId. This goes beyond the schema's pattern description.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool lists all legislation items in a specific database and is used to find legislation IDs for metadata lookup. It distinguishes from sibling tools which focus on case law.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description specifies using the tool to find legislation IDs, but does not explicitly state when not to use it or compare to the sibling 'search' tool. The context is clear enough for legislation-specific tasks.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Look up citation relationships for a case. Critical for verifying if a case is still good law. Use 'citingCases' to see what later cases cite this decision — if many recent cases cite it approvingly, it is strong authority. Use 'citedCases' to see what authorities this case relied on. Use 'citedLegislations' to see what statutes the case references. Returns the full list of citing/cited items.
| Name | Required | Description | Default |
|---|---|---|---|
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| databaseId | Yes | Court database ID (e.g., 'onsc', 'onca', 'csc-scc') | |
| caseId | Yes | Case unique identifier (e.g., '2021onsc8582') | |
| metadataType | Yes | 'citingCases' = what later cases cite this one (check if still good law); 'citedCases' = what this case relies on; 'citedLegislations' = statutes referenced | |
| publishedBefore | No | Date first published on CanLII (YYYY-MM-DD) | |
| publishedAfter | No | Date first published on CanLII (YYYY-MM-DD) | |
| modifiedBefore | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| modifiedAfter | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| changedBefore | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| changedAfter | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| decisionDateBefore | No | Decision date upper bound (YYYY-MM-DD) | |
| decisionDateAfter | No | Decision date lower bound (YYYY-MM-DD) |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must disclose behavioral traits. It states 'Returns the full list of citing/cited items,' which implies a complete list without pagination. However, it does not cover potential limits, error handling, authentication needs, or response structure. For a read-only lookup tool, this is adequate but lacks depth.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single paragraph of four sentences, front-loaded with the core purpose. Every sentence provides useful information without unnecessary words. It is highly concise and well-structured for quick comprehension.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool has 12 parameters (mostly optional date filters) and no output schema, the description focuses on the essential use cases and the returned item list. It covers the critical metadataType options and the tool's importance. However, it does not mention the filtering capabilities or language parameter, which are documented in the schema but not in the description. Overall, it is sufficiently complete for an AI agent to understand the tool's core functionality.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Input schema has 100% description coverage, providing clear meaning for all parameters. The description adds value by explaining the semantic intent of metadataType and the overall workflow, e.g., 'use 'citingCases' to see what later cases cite this decision.' It does not repeat parameter descriptions but enhances understanding, going beyond the baseline of 3.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool's purpose: 'Look up citation relationships for a case.' It specifies the three metadataType values and their meanings (citingCases, citedCases, citedLegislations), making the tool's function very specific and distinguishable from siblings like get_case_citator_tease, though not explicitly differentiating.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description provides clear guidance on when to use each metadataType: 'Use 'citingCases' to see what later cases cite this decision... Use 'citedCases' to see what authorities this case relied on. Use 'citedLegislations' to see what statutes the case references.' It frames the tool as 'critical for verifying if a case is still good law,' but does not mention when not to use it or how it compares to the sibling get_case_citator_tease.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Quick preview of citation relationships (max 5 results). Faster than the full citator. Use this for a quick check on whether a case has been cited, then use get_case_citator for the complete list if needed.
| Name | Required | Description | Default |
|---|---|---|---|
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| databaseId | Yes | Court database ID (e.g., 'onsc', 'onca', 'csc-scc') | |
| caseId | Yes | Case unique identifier (e.g., '2021onsc8582') | |
| metadataType | Yes | Type of citation data to preview |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Discloses the key behavioral trait of returning at most 5 results and being faster than the full citator. However, with no annotations provided, it does not cover other traits like authentication requirements or error handling, which would be valuable for a write operation but this is a read-only preview.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Extremely concise with two sentences that convey purpose, limits, speed advantage, and recommended workflow. No redundant information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The description explains the tool's role and limits but does not describe the output format or behavior beyond the preview, leaving some ambiguity for an agent. However, given the simplicity of the tool and the absence of an output schema, it is minimally adequate.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, with each parameter already well-described in the schema. The description adds no further parameter-level detail beyond the tool's overall purpose, so it aligns with the baseline score.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Clearly states the tool provides a quick preview of citation relationships with a maximum of 5 results, distinguishing it from the sibling 'get_case_citator' which offers the complete list.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Explicitly tells when to use this tool ('quick check') and advises to use the full citator for a complete list if needed, providing clear usage context and alternatives.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
List case law decisions from a specific court database. Use date filters to narrow results. Useful for browsing recent decisions from a specific court. Results are ordered by most recently added. Use get_case_metadata to get full details on a specific case.
| Name | Required | Description | Default |
|---|---|---|---|
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| databaseId | Yes | Court database ID (e.g., 'onsc' for Ontario Superior Court, 'onca' for Ontario Court of Appeal, 'csc-scc' for Supreme Court of Canada) | |
| offset | No | Start position for results (default 0 = most recent) | |
| resultCount | No | Number of results to return (max 10,000, default 20) | |
| publishedBefore | No | Date first published on CanLII (YYYY-MM-DD) | |
| publishedAfter | No | Date first published on CanLII (YYYY-MM-DD) | |
| modifiedBefore | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| modifiedAfter | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| changedBefore | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| changedAfter | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| decisionDateBefore | No | Decision date upper bound (YYYY-MM-DD) | |
| decisionDateAfter | No | Decision date lower bound (YYYY-MM-DD) |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations provided, so description carries full burden. It discloses that results are ordered by most recently added, which is key behavior. However, it does not mention any potential side effects, authorization needs, or rate limits.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two efficient sentences that front-load the main purpose and add relevant usage context. Could be slightly more structured, but overall concise.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the 12 parameters (all documented in schema) and no output schema, the description sufficiently explains the tool's purpose, ordering, and relationship to sibling tools. References get_case_metadata for full details, which helps complete the picture.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100% with clear parameter descriptions. The description adds high-level purpose but does not provide additional meaning beyond what the schema already specifies for parameters.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Description clearly states the tool lists case law decisions from a specific court database, with date filtering capabilities. It explicitly distinguishes from the sibling tool get_case_metadata, which provides full details on a specific case.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Provides clear context for use (browsing recent decisions from a specific court) and mentions an alternative tool (get_case_metadata) for full details. However, it does not explicitly mention when not to use this tool or other alternatives like 'search'.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Get detailed metadata for a specific case including its CanLII URL, citation, decision date, docket number, keywords, and topics. The URL field links directly to the full decision text on canlii.org — always provide this to the user for verification. Use after finding a case via search or browse to get complete details before citing it.
| Name | Required | Description | Default |
|---|---|---|---|
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| databaseId | Yes | Court database ID (e.g., 'onsc', 'onca', 'csc-scc') | |
| caseId | Yes | Case unique identifier from search/browse results (e.g., '2021onsc8582') | |
| publishedBefore | No | Date first published on CanLII (YYYY-MM-DD) | |
| publishedAfter | No | Date first published on CanLII (YYYY-MM-DD) | |
| modifiedBefore | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| modifiedAfter | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| changedBefore | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| changedAfter | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| decisionDateBefore | No | Decision date upper bound (YYYY-MM-DD) | |
| decisionDateAfter | No | Decision date lower bound (YYYY-MM-DD) |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden. It discloses the tool is a read-like retrieval (getting metadata) and includes an instruction to always provide the URL to the user. However, it does not explicitly state it is read-only or mention any permissions or side effects, which weakens transparency.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is two concise sentences. The first states the purpose and output; the second gives usage guidance. Every word adds value, and the structure is front-loaded with the most critical information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The description lists key output fields, providing enough context for an agent to understand return structure despite no output schema. It does not explain all parameters or potential errors, but for a simple retrieval tool, it is complete enough.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so each parameter already has a description. The tool description adds no additional meaning beyond schema, except implying that databaseId and caseId are central. This meets the baseline of 3.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description uses the specific verb 'Get' and targets 'detailed metadata for a specific case'. It lists key outputs (CanLII URL, citation, etc.) and differentiates the tool from search and browsing by stating it provides complete details before citing.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description explicitly guides the agent to use this tool 'after finding a case via search or browse to get complete details before citing it'. This provides clear context for when to invoke it, though it does not explicitly mention when not to use it or name specific alternatives.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
List all available court and tribunal databases in Canada. Returns database IDs needed for other tools. Key databases: onsc (Ontario Superior Court), onca (Ontario Court of Appeal), oncj (Ontario Court of Justice), onscdc (Divisional Court), csc-scc (Supreme Court of Canada), bcsc (BC Supreme Court), abkb (Alberta King's Bench). Use this to discover valid databaseId values for browse and citator tools.
| Name | Required | Description | Default |
|---|---|---|---|
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| publishedBefore | No | Date first published on CanLII (YYYY-MM-DD) | |
| publishedAfter | No | Date first published on CanLII (YYYY-MM-DD) | |
| modifiedBefore | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| modifiedAfter | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| changedBefore | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| changedAfter | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| decisionDateBefore | No | Decision date upper bound (YYYY-MM-DD) | |
| decisionDateAfter | No | Decision date lower bound (YYYY-MM-DD) |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Though no annotations are provided, the description implies a read-only operation (listing databases) and explicitly states it returns database IDs. It does not contradict any annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is concise, using three sentences to convey purpose, examples, and usage guidance. Slightly verbose with examples but overall efficient.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's simplicity and no output schema, the description covers the core purpose and return values. It does not detail the return structure but is sufficient for a listing tool.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
All 9 parameters are fully described in the input schema (100% coverage). The description does not add additional meaning beyond the schema, meriting a baseline score of 3.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool lists all available court and tribunal databases in Canada and returns database IDs needed for other tools. It distinguishes itself from siblings like get_legislation_databases by specifying it provides database IDs for browse and citator tools.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description explicitly advises using this tool to discover valid databaseId values for browse and citator tools, providing clear guidance on when to use. However, it does not mention when not to use or alternatives.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
List all available legislation databases in Canada. Returns database IDs for browsing statutes and regulations. Key databases: ons (Ontario Statutes), onr (Ontario Regulations), cas (Canada Statutes), car (Canada Regulations), bcs (BC Statutes), abs (Alberta Statutes).
| Name | Required | Description | Default |
|---|---|---|---|
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| publishedBefore | No | Date first published on CanLII (YYYY-MM-DD) | |
| publishedAfter | No | Date first published on CanLII (YYYY-MM-DD) | |
| modifiedBefore | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| modifiedAfter | No | Date content last modified on CanLII (YYYY-MM-DD) | |
| changedBefore | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| changedAfter | No | Date metadata or content last changed on CanLII (YYYY-MM-DD) | |
| decisionDateBefore | No | Decision date upper bound (YYYY-MM-DD) | |
| decisionDateAfter | No | Decision date lower bound (YYYY-MM-DD) |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It states the tool returns database IDs and lists key databases, but it does not disclose behavioral traits such as read-only nature, rate limits, or any side effects. For a simple listing tool, this is adequate but not exhaustive.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is extremely concise: two sentences plus a brief list of key databases. It is front-loaded with the purpose and provides immediate value without unnecessary detail.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The tool has 9 optional filter parameters, but the description does not explain their purpose or how to use them effectively. There is no output schema, and the description only mentions 'returns database IDs' without specifying format or structure. This leaves some gaps, but for a simple listing tool it is minimally adequate.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The input schema has 100% description coverage, so the baseline is 3. The description does not add meaning beyond the schema; it only mentions database IDs in the output context. The parameters are well-documented in the schema, so no further elaboration is needed.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool's function: listing all available legislation databases in Canada. It provides specific examples of key databases and what they represent. This distinguishes it from sibling tools like browse_legislation or get_case_citator.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description indicates the tool is for retrieving a list of databases, which is a clear use case. It does not explicitly mention when not to use it or provide alternatives, but the context is sufficient for an AI agent to understand its primary role.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Get metadata for a specific statute or regulation including its CanLII URL, citation, and table of contents. The URL links directly to the full legislation text on canlii.org — always provide this to the user.
| Name | Required | Description | Default |
|---|---|---|---|
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| databaseId | Yes | Legislation database ID (e.g., 'ons' for Ontario Statutes) | |
| legislationId | Yes | Specific legislation ID from browse results |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations exist, so description bears full burden. It reveals what is returned but does not disclose that it is read-only, any side effects, permissions, or rate limits.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences: first states purpose and content, second provides actionable instruction. No wasted words, information is front-loaded.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's simplicity and absence of output schema, the description adequately covers the return content and user instruction. However, it could mention that the IDs come from browse results.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Input schema has 100% description coverage, so the description adds minimal extra meaning beyond the schema's field descriptions. The mention of 'CanLII URL, citation, and table of contents' provides general context but not parameter details.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool retrieves metadata for a specific statute/regulation, including URL, citation, and table of contents, distinguishing it from sibling tools like browse_legislation.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description implies usage (when you need metadata for a specific legislation), but does not provide explicit guidance on when to prefer this over siblings or exclude certain cases.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Search CanLII for cases, legislation, and commentary by keyword. This is the primary entry point for legal research. Returns case citations and titles ranked by relevance — does NOT include keywords, dates, or URLs. Call get_case_metadata on promising results to get full details before citing a case. Search is keyword-based, not semantic — use specific legal terms rather than natural language. Common terms: 'best interests of the child', 'material change in circumstances', 'standard of review', 'duty to consult', 'reasonable expectation of privacy'. Include jurisdiction to narrow results (e.g., 'Ontario', 'Alberta'). Date filters are NOT supported on search. Always cite the CanLII citation and provide the case URL so the user can verify the source.
| Name | Required | Description | Default |
|---|---|---|---|
| query | Yes | Full-text search query. Can include case names, legal concepts, legislation references, or keywords. | |
| language | No | Language: 'en' for English (default), 'fr' for French | en |
| resultCount | No | Number of results to return (1-100, default 10). Keep low for AI context efficiency. | |
| offset | No | Pagination offset (default 0). Use to page through results. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Description fully compensates for missing annotations by disclosing return content (citations and titles only, not keywords/dates/URLs), search nature (keyword-based), limitations (no date filters), and recommended follow-up. No contradictions.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Description is a single paragraph that covers all needed information without wasted words. Could be more structured with bullets, but each sentence adds value and it remains readable.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given no output schema and no annotations, the description provides sufficient context: input, behavior, limitations, and workflow. It covers what the tool returns and what it does not, and directs the agent to next steps. Could mention error handling or permissions, but is complete for a search tool.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, so baseline is 3. Description adds value by noting 'keep low for AI context efficiency' for resultCount, and explaining that query should include jurisdiction to narrow. These go beyond schema field descriptions.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Description clearly states the tool searches CanLII for cases, legislation, and commentary by keyword, and positions it as the primary entry point for legal research. However, it does not explicitly differentiate from sibling tools like browse_legislation or get_case_metadata, though it implies they are for follow-up after search.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Provides explicit when-to-use guidance: 'primary entry point' and after search, 'call get_case_metadata on promising results'. Also explains search is keyword-based, not semantic, and advises including jurisdiction. Does not explicitly list situations where other tools are better, but the workflow is clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
v1.1.4browse_legislationget_case_citatorget_case_citator_teaseget_case_law_decisionsget_case_metadataget_courts_and_tribunalsget_legislation_databasesget_legislation_regulation_metadatasearchScored across 9 tools
Each tool has a distinct purpose: browse_legislation lists legislation items, get_case_citator retrieves full citation relationships, get_case_citator_tease offers a quick preview, get_case_law_decisions lists decisions from a court database, get_case_metadata provides detailed case info, get_courts_and_tribunals lists available court databases, get_legislation_databases lists legislation databases, get_legislation_regulation_metadata fetches legislation details, and search performs keyword searches. No two tools overlap significantly.
Most tools follow a 'get_' prefix (e.g., get_case_metadata, get_courts_and_tribunals), but 'browse_legislation' uses 'browse_' and 'search' is a bare verb. This slight inconsistency is minor and does not hinder readability.
Nine tools is appropriate for a legal research server. Each tool covers a core function—searching, browsing cases and legislation, citators, and metadata retrieval—without being excessive or insufficient.
The surface covers essential read-only legal research operations: search, browse, citator, and metadata. Minor gaps include lack of date filters on search (mitigated by jurisdiction keywords) and no direct full-text retrieval (URLs provided instead). Overall, it's well-rounded.
MCP for CanLII: Canadian case law and legislation metadata (federal, provincial, territorial).
Resolve, search and verify legal citations against the official sources, with provenance.
Korean law: statutes, precedents, ordinances, treaties and citation verification (법제처 API).
Wrapper for the official LegalOne API (Thomson Reuters / Novajus, Premium package): lawsuits and lit
