German Legal MCP Server

⚠️ WARNING: Work in Progress
This project is currently under active development and not production-ready. APIs may change without notice, and features may be incomplete or unstable. Use at your own risk.

A Model Context Protocol (MCP) server for German legal research, providing unified access to multiple legal databases.

Supported Sources

| Source | Status | Prefix | Authentication | |--------|--------|--------|----------------| | Bundes- & Landesrecht | ✅ Available | legis: | None (public) | | Rechtsprechung im Internet | ✅ Available | rii: | None (public) | | RIS Österreich | ✅ Available | ris: | None (public OGD API) | | InfoCuria (CJEU) | ✅ Available | icu: | None (public) | | EUR-Lex | ✅ Available | eul: | None (public) | | DIP Bundestag | ✅ Available | dip: | Public key included | | arXiv | ✅ Available | arxiv: | None (public) | | nautos.de | ✅ Available | nautos: | Required (IP or credentials) |

Features

Bundes- & Landesrecht (legis:* tools)

• Federal and state legislation — BUND (all federal laws) + 16 Länder (all states)
• No authentication — free public access, no rate limits
• Unified interface — one set of tools for all jurisdictions
• Full text search — search across state legislation (Länder only)
• Resilient input — BUND accepts "§ 823", "823", "Art. 1", "Paragraph 51"
• Pandoc-compatible Markdown — clean conversion with Turndown
• Save to file — save_path parameter to avoid context pollution
• Available states: BUND, BB, BW, BY, BE, HB, HE, HH, MV, NI, NW, RP, SL, SN, ST, SH, TH

Rechtsprechung im Internet (rii:* tools)

• Federal court decisions — BVerfG, BGH, BVerwG, BFH, BAG, BSG, BPatG (from 2010)
• Bavarian state courts — AG, LG, OLG, VG, VGH, FG, ArbG, LAG, BayVerfGH via gesetze-bayern.de
• No authentication — free public access
• Full text search — search across all federal court decisions
• Kurztext/Langtext — summary or full text via part parameter
• Randnummern — formatted as [Rn. 5]{.rn} (pandoc spans)
• Save to file — save_path parameter to avoid context pollution

RIS Österreich (ris:* tools)

• Austrian federal, state & case law — consolidated Bundesrecht and Landesrecht (all 9 Bundesländer, or filter to one via bundesland; results tagged with their Bundesland), plus Judikatur (OGH/OLG/LG via Justiz; VwGH, VfGH, BVwG and others via the court filter)
  • Note: bundesland on application="landesrecht" returns that state's consolidated law (LrKons). Case law is a separate application — for raw state judikatur use application="judikatur" with the appropriate court (e.g. Lvwg for a Landesverwaltungsgericht), not bundesland.
• No authentication — free public Open Government Data REST API (data.bka.gv.at/ris/api/v2.6)
• Latest-first — sort="date" for the newest decisions; Judikatur Rechtssätze link their full decision text (Entscheidungstext) for ris:get
• Navigate & read statutes — ris:toc law="ABGB" lists the §§ with headings; ris:get_norm law="ABGB" paragraph="1295" returns a single §
• Surgical retrieval — ris:get section=… returns only a Randnummer (Rn 5), an Rn range (Rn 5-9), a line range (lines:1-40), or a heading (Spruch) — all token-preserving
• Pandoc-compatible Markdown — Randnummern as [Rn. 5]{.rn} spans; document HTML converted with Cheerio + Turndown
• Structured metadata — Geschäftszahl, Entscheidungsdatum, ECLI, issuing court/organ
• Save to file — save_path parameter to avoid context pollution
• ⚠️ Austrian law — for German case law use rii:*, for German legislation use legis:*

InfoCuria — CJEU (icu:* tools)

• EU Court of Justice case law — judgments, opinions, orders from CJEU and General Court
• No authentication — free public access via InfoCuria API
• Multilingual — documents available in all EU languages (default: DE)
• Flexible case lookup — accepts case numbers (C-476/17), CELEX numbers, or internal IDs
• Randnummern — formatted as [Rn. 5]{.rn}
• Partial content — section parameter for Rn ranges, headings, or line ranges
• Save to file — save_path parameter to avoid context pollution

EUR-Lex (eul:* tools)

• EU legislation — directives, regulations, decisions, treaties (TFEU, TEU)
• No authentication — free public access via Cellar REST API and SPARQL
• Multilingual — documents available in all EU languages (default: DE)
• CELEX lookup — retrieve by CELEX number (e.g., "32016R0679" for GDPR)
• SPARQL search — search by title keywords, filter by resource type
• Partial content — section parameter for articles (Art. 5), headings, or line ranges
• Save to file — save_path parameter to avoid context pollution

DIP Bundestag (dip:* tools)

• Parliamentary documents — Bundestagsdrucksachen (Gesetzentwürfe, Beschlussempfehlungen, Anfragen)
• Legislative processes — Vorgänge with status tracking and linked documents
• Debate transcripts — full text search across Plenarprotokolle (BT and BR)
• Full text retrieval — extracted text including Gesetzesbegründungen, with section support
• Public API key included — works out of the box (key valid until end of May 2027, override via env var)
• Save to file — save_path parameter to avoid context pollution

arXiv (arxiv:* tools)

• Preprint search — search by keywords, author, title, abstract, or category
• Metadata + abstract — default response without full text fetch (token-efficient)
• HTML full text — Markdown conversion for papers from ~2024+ (LaTeXML HTML)
• PDF fallback — older papers without HTML return abstract + PDF link
• No authentication — free public API, no rate limits beyond ~1 req/3s
• Save to file — save_path parameter to avoid context pollution

nautos.de (nautos:* tools)

• DIN/EN/ISO standards — search and retrieve technical standards from nautos.de
• Two-phase document retrieval — outline (metadata + TOC) first, then sections on demand
• Automatic authentication — IP-based login (auto-detected), user-based login fallback
• Structured TOC — hierarchical table of contents with section IDs for navigation
• File cache — 30-day TTL, persistent across restarts (~/.local/share/german-legal-mcp/cache/nautos/)
• Save to file — save_path parameter to dump full document to disk

Install in Claude Desktop (one-click bundle)

The easiest way to use this server in Claude Desktop is the packaged MCP Bundle (.mcpb) — no Node.js, no npx, no config file.

1. Download german-legal-mcp.mcpb from the latest release.
2. In Claude Desktop open Settings → Extensions and drag the .mcpb onto the window (or use Install…).
3. Optionally set the DIP key or nautos credentials in the extension's settings — everything else works out of the box.

The bundle ships the public, no-authentication sources and is cross-platform (macOS and Windows, Apple Silicon and Intel) — Claude Desktop supplies the Node.js runtime, so a single download works everywhere.

Quick Start with npx

npx @metaneutrons/german-legal-mcp

or add your MCP client config (e.g., claude_desktop_config.json):

{
  "mcpServers": {
    "german-legal": {
      "command": "npx",
      "args": ["-y", "@metaneutrons/german-legal-mcp"]
    }
  }
}

Environment Variables

Provider Enablement

| Variable | Default | Description | |----------|---------|-------------| | GLMCP_STATE_DIR | Platform default | Root directory for logs, sessions, caches, metrics, daemon sockets and locks. | | GLMCP_LOG_LEVEL | info | Structured log level. | | GLMCP_LEGIS_ENABLED | true | Bundes- & Landesrecht | | GLMCP_RII_ENABLED | true | Rechtsprechung im Internet | | GLMCP_RIS_ENABLED | true | RIS Austria (federal law + case law) | | GLMCP_ICU_ENABLED | true | InfoCuria (CJEU) | | GLMCP_EUL_ENABLED | true | EUR-Lex | | GLMCP_DIP_ENABLED | true | DIP Bundestag (auto-disabled after 2027-06-01 without own key) | | GLMCP_DIP_API_KEY | Public key | Override the bundled public API key | | GLMCP_ARXIV_ENABLED | true | arXiv preprint search | | GLMCP_NAUTOS_ENABLED | Auto | nautos.de. Auto-enabled with tenant key or credentials, auto-disabled without. |

nautos.de Configuration

| Variable | Required | Description | |----------|----------|-------------| | GLMCP_NAUTOS_TENANT_KEY | For IP-based | Tenant key (e.g., DWW). Enables IP-based authentication. | | GLMCP_NAUTOS_USERNAME | For user-based | nautos.de account username | | GLMCP_NAUTOS_PASSWORD | For user-based | nautos.de account password | | GLMCP_NAUTOS_TENANT_ID | No | Tenant ID (auto-detected from login response) |

Authentication: IP-based login is tried first (requires GLMCP_NAUTOS_TENANT_KEY). If it fails and credentials are set, user-based login is attempted as fallback.

Tools

Bundes- & Landesrecht

| Tool | Description | |------|-------------| | legis:search | Search federal and state legislation. Parameter: query, state (e.g., "BW", "BE"), limit. Note: BUND does not support search. | | legis:get | Retrieve a specific law/norm. BUND: id = "law/section" (e.g., "bgb/823"). Länder: id from search results. Optional save_path. | | legis:toc | Compact table of contents for a law — section numbers and headings. Supports from/to range and depth filter. BUND: id = law abbreviation (e.g., "bgb"). | | legis:states | List available jurisdictions with implementation status. |

Rechtsprechung im Internet

| Tool | Description | |------|-------------| | rii:search | Search for court decisions. Returns list with doc IDs, titles, and snippets. Use source: "BY" for Bavarian state courts. | | rii:get_decision | Retrieve full text of a court decision by doc ID. part: K (Kurztext) or L (Langtext, default). Optional save_path to save to file. Use source: "BY" for gesetze-bayern.de IDs. |

RIS Österreich

| Tool | Description | |------|-------------| | ris:search | Search the Austrian RIS. application: "bundesrecht"/"landesrecht" (consolidated federal/state law) or "judikatur" (case law; set court: Justiz/Vwgh/Vfgh/Bvwg). sort="date" for the latest decisions. Landesrecht results are tagged with their Bundesland (filter to one state's consolidated law with bundesland). Judikatur hits are Rechtssätze that link their full decision text (Entscheidungstext) for ris:get. | | ris:get | Retrieve a RIS document as Markdown by content_url (from search) or id + applikation. section returns only part — Rn 5, Rn 5-9, lines:1-40, or a heading like Spruch — for token-preserving reads. Optional save_path. | | ris:get_norm | Retrieve a single § of a consolidated law — law="ABGB" paragraph="1295". application: bundesrecht (federal) or landesrecht (+ bundesland). The token-preserving way to read one paragraph. | | ris:toc | Table of contents (Inhaltsverzeichnis) of a consolidated law — its §§ with headings — to navigate before ris:get_norm. law="ABGB" (full title if an abbreviation fails). application + bundesland as above. |

InfoCuria — CJEU

| Tool | Description | |------|-------------| | icu:search | Search CJEU decisions and opinions. Returns case numbers, ECLI, dates, and document IDs. | | icu:get_document | Retrieve full text by case number (C-476/17) or CELEX number. Supports section (Rn ranges, headings, line ranges) and save_path. |

EUR-Lex

| Tool | Description | |------|-------------| | eul:search | Search EU legislation via SPARQL. Filter by type (directive, regulation, decision, treaty). | | eul:get_document | Retrieve EU legislation by CELEX number (e.g., "32016R0679" for GDPR). Supports section (Art. 5, Artikel 5-10, headings, line ranges) and save_path. |

DIP Bundestag

| Tool | Description | |------|-------------| | dip:search | Search Bundestagsdrucksachen by title. Filter by type (Gesetzentwurf, Anfrage, etc.), Wahlperiode, date range. | | dip:get | Retrieve full text of a Drucksache by Dokumentnummer (e.g., "19/27426"). Supports section and save_path. | | dip:search_vorgang | Search legislative processes (Vorgänge) with status and linked Drucksachen. | | dip:search_plenarprotokoll | Full text search across parliamentary debate transcripts (BT and BR). |

arXiv

| Tool | Description | |------|-------------| | arxiv:search | Search preprints by keywords, author, title, abstract, or category. Returns metadata + abstract. | | arxiv:get | Retrieve paper by arXiv ID. Default: metadata + abstract. With section or save_path: HTML full text as Markdown (~2024+, older: PDF link). |

nautos.de

| Tool | Description | |------|-------------| | nautos:search | Search DIN/EN/ISO standards by document number. Returns acCode, title, date, type. | | nautos:get_document | Retrieve standard by acCode. Returns outline (metadata + TOC) by default; use section for specific parts, save_path to save full document. |

Two-Phase Document Retrieval

All document tools use a two-phase approach to avoid flooding the LLM context:

1. Outline — first call returns title, metadata, table of contents, and a preview
2. Section — request specific parts by Randnummer, heading, or line range (served from cache)
3. Save to file — write full document to disk, return metadata only

Section formats: "Rn 5", "Rn 5-12", "lines:100-200", or any heading text (fuzzy match).

Markdown Output

Documents are converted to pandoc-compatible Markdown:

• Randnummern: [Rn. 5]{.rn} (bracketed spans)
• Footnotes: ^[inline footnote text] (pandoc inline footnotes)

Development

npm test              # Run tests
npm run test:watch    # Watch mode
npm run test:coverage # Coverage report

MCP Inspector

npx @modelcontextprotocol/inspector node dist/index.js

Commit Convention

This repo uses Conventional Commits enforced via Husky + commitlint.

Types: feat, fix, docs, style, refactor, perf, test, chore, ci, build, revert

Scopes: legis, rii, ris, icu, eul, dip, nautos, core, deps, config

Architecture

• Manifest-driven providers — startup, help, shutdown and public/private distribution use one checked provider manifest

• Cheerio + Turndown for HTML → pandoc Markdown conversion

• Zod for input validation

• Axios for HTTP requests (Legis, RII, RIS, InfoCuria, EUR-Lex, DIP, arXiv, nautos)

• Structured JSON errors — all providers return BaseError.toJSON() with code, userMessage, recoveryHint; Axios errors auto-wrapped; DNS failures fail fast

• Conversion validation — all HTML→Markdown providers validate output is non-empty; detects upstream layout changes early

• Tools namespaced by source (legis:, rii:, ris:, icu:, eul:, dip:, arxiv:, nautos:)

License

GPL-3.0 - See LICENSE for details.