# Rechtsinformationen Bund DE MCP Server
An MCP (Model Context Protocol) server that provides access to the official German Federal Legal Information Portal (rechtsinformationen.bund.de). **Any AI agent can use this server for German legal questions** to provide authoritative, fact-based answers with proper legal citations from official sources.
## 🚀 Quick Setup
**The fastest way to get started:**
1. **Run the setup script:**
```bash
./quick-setup.sh
```
2. **Restart Claude Desktop completely** (or your MCP client)
3. **Test with:** "Wie lange kann ich in Elternzeit gehen?"
## 🎯 What This Server Provides
**AI agents will automatically use this MCP server for:**
- **German legal questions** ("What happens if I miss a Jobcenter appointment?")
- **Legal rights and obligations** ("How long can I take parental leave?")
- **Court decisions and precedents** ("Recent BGH decisions on trademark law")
- **Specific law lookups** ("What does § 32 SGB II say?")
- **Administrative law questions** ("When do I need a hearing in administrative proceedings?")
**Purpose:** Ensures all German legal answers are grounded in official sources with proper citations.
## ✨ Features
### Core Capabilities
- **Full-text search** across German federal laws and legislation
- **Case law search** through German federal court decisions (BGH, BVerfG, BAG, BFH, BSG, BVerwG)
- **Intelligent search** with English-to-German translation and misconception correction
- **German compound word decomposition** (e.g., "Mieterhöhungsantrag" → "Mieterhöhung")
- **HTML URLs for users** (clickable, readable documents)
- **Model-agnostic** - works with Claude, Qwen, DeepSeek, LLaMA, and other models
### Recent Improvements (2025-10-06)
✅ **HTML URLs**: Returns human-readable web links, not just JSON API URLs
✅ **Compound word handling**: Decomposes German compound words for better search
✅ **Fallback search**: Never returns zero results for valid queries
✅ **English translation**: Automatically translates English legal terms to German
✅ **Type coercion**: Works with models that pass strings instead of numbers
## 📚 Available Tools
The server provides **6 specialized tools** with intelligent routing:
### 1. 🧠 semantische_rechtssuche (PRIMARY TOOL)
**Intelligent Legal Search** - Use this FIRST for any German legal question
**What it does automatically:**
- ✓ Translates English → German ("employee rights" → "Arbeitnehmerrechte")
- ✓ Corrects misconceptions ("Überprüfungsantrag" → "Widerspruch")
- ✓ Extracts legal references (§ patterns)
- ✓ Searches multiple related terms
- ✓ Returns both legislation AND case law
**What it does NOT do:**
- ✗ Does NOT generate semantically similar terms (agent must provide variations)
- ✗ Does NOT try multiple query phrasings automatically
- ✗ Does NOT use ML embeddings (uses keyword matching + Fuse.js fuzzy search)
**Parameters:**
- `query` (required): Search query in German or English
- `threshold` (optional): Fuzzy match threshold 0.0-1.0 (default: 0.3)
- `limit` (optional): Max results (default: 10, max: 100)
**URLs returned:**
```
🌐 READ ONLINE (HTML): https://testphase.rechtsinformationen.bund.de/.../regelungstext-1.html
📊 API ACCESS (JSON): https://testphase.rechtsinformationen.bund.de/v1/legislation/...
```
### 2. 🇩🇪 deutsche_gesetze_suchen (SECONDARY TOOL)
Search German federal legislation (laws, ordinances)
**When to use:**
- Follow-up after semantische_rechtssuche
- Legislation-only results needed
- Searching for specific law abbreviations (BEEG, BGB, SGB)
**Limitations:**
⚠️ Date filters may exclude relevant results
### 3. ⚖️ rechtsprechung_suchen (SECONDARY TOOL)
Search German court decisions
**When to use:**
- Follow-up after semantische_rechtssuche
- Court-specific filtering needed
- Searching for specific judges or case types
**Common courts:**
- BGH (Federal Court of Justice)
- BVerfG (Constitutional Court)
- BAG (Federal Labour Court)
- BFH (Federal Fiscal Court)
- BSG (Federal Social Court)
- BVerwG (Federal Administrative Court)
### 4. 🔍 alle_rechtsdokumente_suchen (SECONDARY TOOL)
Comprehensive search across all document types
**When to use:**
- After other specialized tools
- Mixed results needed (legislation + case law)
- Broad topic exploration
### 5. 📄 dokument_details_abrufen (RETRIEVAL TOOL)
Get full text of specific documents
**When to use:**
- After finding document in search results
- Need complete document text (searches only return snippets)
- Want HTML or XML format
### 6. 🏛️ gesetz_per_eli_abrufen (RETRIEVAL TOOL)
Get legislation by ELI identifier
**When to use:**
- Have specific ELI from search results
- Need exact version/date of legislation
## 🤖 Model Compatibility
### Tested & Working
- ✅ **Claude 3.5 Sonnet** - Excellent tool selection, proper citations
- ✅ **Qwen 2.5-72B** - Best open-source option, good German support
- ✅ **DeepSeek-R1** - Strong reasoning, needs recursion limit
- ✅ **LLaMA 3.3-70B** - Reliable, good for straightforward queries
- ✅ **GLM-4.6** - Works with type coercion fixes
### Recommended Agent Configuration (LibreChat)
For best results with any model:
```json
{
"name": "German Legal Research Assistant",
"description": "Searches official German legal database",
"model": "qwen2.5:72b",
"tools": [
"mcp__rechtsinformationen__semantische_rechtssuche",
"mcp__rechtsinformationen__deutsche_gesetze_suchen",
"mcp__rechtsinformationen__rechtsprechung_suchen"
],
"recursionLimit": 5,
"temperature": 0.3,
"instructions": "CRITICAL: Always use semantische_rechtssuche FIRST. If search returns results, STOP immediately and generate answer. Maximum 2-3 tool calls total. MUST include ALL URLs in 'Quellen:' or 'Sources:' section."
}
```
**Key settings:**
- `recursionLimit: 5` - Prevents endless searching
- `temperature: 0.3` - More deterministic for legal queries
- Stop condition - Generate answer immediately after finding results
## 📦 Installation
### Quick Setup
```bash
git clone <repo-url>
cd rechtsinformationen
./quick-setup.sh
```
### Manual Installation
```bash
npm install
npm run build
npm test # Should show passing tests
```
### Claude Desktop Configuration
**macOS:** Edit `~/Library/Application Support/Claude/claude_desktop_config.json`
```json
{
"mcpServers": {
"rechtsinformationen": {
"command": "node",
"args": ["/absolute/path/to/rechtsinformationen/dist/index.js"]
}
}
}
```
**Windows:** Edit `%APPDATA%/Claude/claude_desktop_config.json`
```json
{
"mcpServers": {
"rechtsinformationen": {
"command": "node",
"args": ["C:\\absolute\\path\\to\\rechtsinformationen\\dist\\index.js"]
}
}
}
```
**Important:**
- Use absolute paths (not relative like `./dist/index.js`)
- Restart Claude Desktop completely after config changes
- Run `npm run check-config` to verify setup
### LibreChat Agent Configuration
For optimal performance with LibreChat and Ollama models (Qwen, DeepSeek, LLaMA):
```json
{
"name": "German Legal Research Assistant",
"model": "qwen2.5:72b",
"provider": "ollama",
"recursionLimit": 5,
"temperature": 0.3,
"instructions": "CRITICAL RULES:\n- MAXIMUM 2-3 tool calls per query\n- STOP searching after finding 3+ relevant documents\n- ALWAYS include URLs in 'Quellen' section\n- Use semantische_rechtssuche first\n\nCitation Format (MANDATORY):\n## Quellen\n1. [Law name] - [URL]\n2. [Law name] - [URL]",
"tools": [
"semantische_rechtssuche_mcp_rechtsinformationen",
"deutsche_gesetze_suchen_mcp_rechtsinformationen",
"rechtsprechung_suchen_mcp_rechtsinformationen"
]
}
```
**Key Settings:**
- **recursionLimit: 5** - Prevents endless searching (typical issue with some models)
- **temperature: 0.3** - Accuracy over creativity for legal research
- **STOP instructions** - Forces agent to synthesize answer after finding results
- **Citation requirements** - Mandatory URL inclusion in responses
See [LIBRECHAT_AGENT_CONFIG.md](LIBRECHAT_AGENT_CONFIG.md) for complete configuration details.
## 🧪 Testing & Evaluation
### Run Tests
```bash
# Run golden test cases
npm test
# Test API connectivity
npm run test:api
# Verify complete setup
npm run verify
```
### Agentic Evaluation
To evaluate agent performance with different models:
```bash
# Analyze LibreChat conversation exports
node tests/eval-simple.js tests/your-conversation.json
```
**Metrics tracked:**
- Tool call efficiency (target: ≤3 calls)
- Document accuracy (found correct ECLI/ELI)
- Citation completeness (URLs in sources)
- Recursion safety (no limit hits)
- Answer quality (comprehensive + cited)
See [AGENTIC_EVAL_GUIDE.md](AGENTIC_EVAL_GUIDE.md) for detailed evaluation framework.
## 🔧 Troubleshooting
### Common Issues
#### 1. No Search Results
```bash
# Test API connectivity
npm run test:api
# Check if you have internet connection
curl https://testphase.rechtsinformationen.bund.de/v1/legislation
```
#### 2. Server Won't Start
```bash
# Check Node.js version (needs v18+)
node --version
# Rebuild
npm install && npm run build
```
#### 3. Recursion Limit Hit
**Symptom:** Agent makes 10+ tool calls without stopping
**Solution:**
- Set `recursionLimit: 5` in agent config
- Add explicit STOP instructions
- Use semantische_rechtssuche as primary tool
#### 4. Missing Citations in Output
**Symptom:** Agent doesn't include URLs despite MCP response containing them
**Solution:**
- This is a model behavior issue, not server issue
- Strengthen instructions: "MUST include ALL URLs"
- Consider agentic architecture with dedicated citation agent
#### 5. Schema Validation Errors
**Symptom:** "Received tool input did not match expected schema"
**Solution:** ✅ Fixed - server now handles string→number type coercion
## 📖 Usage Examples
### Simple Query
```
User: "Wie lange kann ich in Elternzeit gehen?"
Agent: Uses semantische_rechtssuche("Elternzeit Dauer")
→ Finds BEEG § 15
→ Answer: Up to 3 years per child
Sources:
1. https://testphase.rechtsinformationen.bund.de/.../regelungstext-1.html
```
### Compound Word Query
```
User: "Was passiert bei einem Mieterhöhungsantrag?"
Agent: Uses semantische_rechtssuche("Mieterhöhungsantrag")
→ Decomposes to "Mieterhöhung"
→ Finds § 558 BGB
→ Answer: Rent increase procedures
Sources:
1. https://testphase.rechtsinformationen.bund.de/.../regelungstext-1.html
```
### English Query
```
User: "What are employee rights during company restructuring?"
Agent: Uses semantische_rechtssuche(translates to "Arbeitnehmerrechte Betriebsumstrukturierung")
→ Finds KSchG, BetrVG
→ Answer: Dismissal protection and works council participation
Sources:
1. https://testphase.rechtsinformationen.bund.de/.../regelungstext-1.html
```
## 🏗️ Architecture
### How It Works
```
User Query
↓
AI Agent (Claude/Qwen/etc)
↓
MCP Server (this project)
↓
rechtsinformationen.bund.de API
↓
German Federal Legal Database
```
**Communication:** Local stdio (no HTTP ports)
**Data Flow:** Real-time API calls for each query
**URLs:** Returns both HTML (users) and JSON (developers)
### Intelligent Search Features
**1. English Translation**
```typescript
"employee rights" → "Arbeitnehmerrechte"
"data protection" → "Datenschutz"
"dismissal" → "Kündigung"
```
**2. Misconception Correction**
```typescript
"Überprüfungsantrag" → ["Widerspruch", "Rücknahme", "Widerruf"]
"§ 535 BGB Mieterhöhung" → "§ 558 BGB" (correct law)
```
**3. Compound Word Decomposition**
```typescript
"Mieterhöhungsantrag" → "Mieterhöhung" (309 results)
"Kündigungsschutzantrag" → "Kündigungsschutz"
"Sozialhilfeantrag" → "Sozialhilfe"
```
**4. Legal Reference Extraction**
```typescript
Detects: § 44 SGB X, Art. 3 GG, § 558 Abs. 2 BGB
Validates: Law abbreviations (BEEG, BGB, SGB, etc.)
```
## 📊 API Source
**Base URL:** `https://testphase.rechtsinformationen.bund.de/v1`
**Documentation:** https://docs.rechtsinformationen.bund.de
**Standards:** ELI (European Legislation Identifier), ECLI (European Case Law Identifier)
**Status:** Trial service - may be subject to changes
**Coverage:**
- ✅ Current federal legislation
- ✅ Federal court decisions (2010-2024)
- ✅ Historical versions of laws
- ⚠️ Amendment laws (partial coverage)
- ❌ Legislative materials (not included)
## ⚠️ Known Limitations
### 1. Date Filtering Issues
**Problem:** Temporal filters may exclude relevant results when laws enacted in one year become effective in another.
**Example:** Searching for "§ 44 SGB X Änderung 2021" with date filter 2021 misses the 7. SGB-IV-Änderungsgesetz from June 2020 (effective January 1, 2021).
**Workaround:** Search without date filters, manually review effective dates.
### 2. Amendment Law Discovery
**Problem:** Amendment laws are poorly indexed and may not show which paragraphs they modify.
**Workaround:**
- Search for "BGBl [year]" to find Federal Law Gazette entries
- Look for "Artikelgesetz" or amendment law names
- Search effective dates like "2021-01-01 Inkrafttreten"
### 3. Historical Versions
**Problem:** Only current versions easily accessible through ELI identifiers.
**Workaround:** Search Federal Law Gazette references for specific dates.
### 4. Model Behavior
**Citations not appearing:** Some models ignore citation instructions despite clear guidance in MCP response. This is a model limitation, not server issue.
**Solution:** Use agent configuration with explicit citation requirements or consider multi-agent architecture.
## 🚀 Recent Fixes (2025-10-06)
### Major Improvements
✅ **HTML URLs for Users**
- Returns clickable HTML links instead of JSON API URLs
- Users can now read laws in browsers
- Both HTML and JSON URLs provided
✅ **German Compound Word Handling**
- Decomposes "Mieterhöhungsantrag" → "Mieterhöhung"
- Removes suffixes: -antrag, -verfahren, -klage, -gesetz, -verordnung
- Special handling for common legal terms
✅ **Fallback Search**
- Never returns zero results for valid queries
- Searches with original query if no legal references found
- Provides helpful suggestions when nothing found
✅ **Type Coercion**
- Handles models passing "10" (string) instead of 10 (number)
- Schema validation now works with GLM-4.6 and similar models
✅ **Model-Agnostic Instructions**
- Removed Claude-specific language
- Works with any AI model
- Clear imperative instructions
## 📝 Development
### Build Commands
```bash
npm run build # Compile TypeScript
npm run dev # Development mode with tsx
npm start # Run production build
npm test # Run test suite
```
### Helper Commands
```bash
npm run claude-config # Generate config for Claude Desktop
npm run check-config # Show config file path
npm run verify # Complete verification
npm run setup # Install + build + test
```
### Project Structure
```
src/
├── index.ts # Main MCP server
tests/
├── golden_case_tests.json # Test cases
├── test-golden.js # Test runner
├── eval-simple.js # Agent evaluation
debug/
├── test-*.js # API debugging tools
```
## 🤝 Contributing
Contributions welcome! Areas for improvement:
1. **More compound word patterns** - Expand German word decomposition
2. **Better concept mappings** - Add common legal misconceptions
3. **English translation coverage** - More legal term translations
4. **Historical version access** - Better handling of law amendments
5. **Literature search** - Add `/v1/literature` endpoint support
## 📄 License
MIT
## 🔗 Related Documentation
- [CLAUDE.md](CLAUDE.md) - Detailed instructions for Claude Code
- [AGENTIC_EVAL_GUIDE.md](AGENTIC_EVAL_GUIDE.md) - Agent evaluation framework
- [LIBRECHAT_AGENT_CONFIG.md](LIBRECHAT_AGENT_CONFIG.md) - LibreChat configuration
- [RECOMMENDED_MODELS.md](RECOMMENDED_MODELS.md) - Model comparison and recommendations
- [FIXES_APPLIED.md](FIXES_APPLIED.md) - Detailed change log
---
**Last Updated:** 2025-10-06
**Version:** 1.1.0
**Status:** Production-ready with test phase API
