Croatian Law MCP Server

The Narodne novine alternative for the AI age.

Query 4,531 Croatian laws -- from the Cybersecurity Act and Criminal Code to the Maritime Code, Obligations Act, and more -- directly from Claude, Cursor, or any MCP-compatible client.

If you're building legal tech, compliance tools, or doing Croatian legal research, this is your verified reference database.

Built by Ansvar Systems -- Stockholm, Sweden

Why This Exists

Croatian legal research is scattered across Narodne novine, zakon.hr, and EUR-Lex. Whether you're:

• A lawyer validating citations in a brief or contract
• A compliance officer checking if a Croatian statute is still in force
• A legal tech developer building tools on Croatian law
• A researcher tracing legislative history from the Official Gazette

...you shouldn't need 47 browser tabs and manual PDF cross-referencing. Ask Claude. Get the exact provision. With context.

This MCP server makes Croatian law searchable, cross-referenceable, and AI-readable.

Quick Start

Use Remotely (No Install Needed)

Connect directly to the hosted version -- zero dependencies, nothing to install.

Endpoint: https://croatian-law-mcp.vercel.app/mcp

| Client | How to Connect | |--------|---------------| | Claude.ai | Settings > Connectors > Add Integration > paste URL | | Claude Code | claude mcp add croatian-law --transport http https://croatian-law-mcp.vercel.app/mcp | | Claude Desktop | Add to config (see below) | | GitHub Copilot | Add to VS Code settings (see below) |

Claude Desktop -- add to claude_desktop_config.json:

{
  "mcpServers": {
    "croatian-law": {
      "type": "url",
      "url": "https://croatian-law-mcp.vercel.app/mcp"
    }
  }
}

GitHub Copilot -- add to VS Code settings.json:

{
  "github.copilot.chat.mcp.servers": {
    "croatian-law": {
      "type": "http",
      "url": "https://croatian-law-mcp.vercel.app/mcp"
    }
  }
}

Use Locally (npm)

npx @ansvar/croatian-law-mcp

Claude Desktop -- add to claude_desktop_config.json:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "croatian-law": {
      "command": "npx",
      "args": ["-y", "@ansvar/croatian-law-mcp"]
    }
  }
}

Cursor / VS Code:

{
  "mcp.servers": {
    "croatian-law": {
      "command": "npx",
      "args": ["-y", "@ansvar/croatian-law-mcp"]
    }
  }
}

Example Queries

Once connected, just ask naturally:

• "What does the Croatian Cybersecurity Act say about incident reporting?"
• "Show me Article 266 of the Croatian Criminal Code on unauthorized computer access"
• "Find provisions about personal data in Croatian law"
• "What EU directives does the Croatian GDPR Implementation Act transpose?"
• "Which Croatian laws implement the NIS2 Directive?"
• "Is the Critical Infrastructures Act still in force?"
• "Compare data protection provisions across Croatian statutes"

What's Included

| Category | Count | Details | |----------|-------|---------| | Statutes | 4,531 laws | Full Croatian legislation corpus (1990-2026) | | Provisions | 157,667 articles | Full-text searchable with FTS5 (unicode61 tokenizer) | | EU Cross-References | 4,407 references | 816 EU directives and regulations | | Legal Definitions | 1,076 terms | Auto-extracted from definition articles | | Database Size | ~253 MB | Optimized SQLite, portable | | Daily Updates | Automated | Freshness checks against Narodne novine |

Verified data only -- every provision is ingested from official Narodne novine ELI endpoints. Zero LLM-generated content.

See It In Action

Why This Works

Verbatim Source Text (No LLM Processing):

• All statute text is ingested from official Narodne novine (Official Gazette) ELI endpoints
• Provisions are returned unchanged from SQLite FTS5 database rows
• Zero LLM summarization or paraphrasing -- the database contains regulation text, not AI interpretations

Smart Context Management:

• Search returns ranked provisions with BM25 scoring (safe for context)
• Provision retrieval gives exact text by law name + article number
• Cross-references help navigate without loading everything at once

Technical Architecture:

Narodne novine CSV index --> Census --> ELI fetch --> Parse --> SQLite --> FTS5 snippet() --> MCP response
                              |                        |
                        Full corpus enum        Verbatim database query

Traditional Research vs. This MCP

| Traditional Approach | This MCP Server | |---------------------|-----------------| | Search Narodne novine by issue number | Search by plain Croatian or English text | | Navigate multi-chapter statutes manually | Get the exact provision with context | | Manual cross-referencing between laws | build_legal_stance aggregates across sources | | "Is this statute still in force?" -> check manually | check_currency tool -> answer in seconds | | Find EU basis -> dig through EUR-Lex | get_eu_basis -> linked EU directives instantly | | Check 5+ sites for updates | Daily automated freshness checks | | No API, no integration | MCP protocol -> AI-native |

Available Tools (12)

Core Legal Research Tools (8)

| Tool | Description | |------|-------------| | search_legislation | FTS5 search on 157,667 provisions with BM25 ranking | | get_provision | Retrieve specific provision by law name + article | | validate_citation | Validate citation against database (zero-hallucination check) | | build_legal_stance | Aggregate citations from statutes and cross-references | | format_citation | Format citations per Croatian conventions | | check_currency | Check if statute is in force, amended, or repealed | | list_sources | Data provenance information | | about | Server metadata |

EU Law Integration Tools (4)

| Tool | Description | |------|-------------| | get_eu_basis | Get EU directives/regulations for Croatian statute | | get_croatian_implementations | Find Croatian laws implementing EU act | | search_eu_implementations | Search EU documents with Croatian implementation counts | | validate_eu_compliance | Check implementation status |

EU Law Integration

4,407 cross-references linking Croatian statutes to EU law, with bi-directional lookup.

| Metric | Value | |--------|-------| | EU References | 4,407 cross-references | | EU Documents | 816 unique directives and regulations | | Directives | Auto-extracted from statute text | | Regulations | Auto-extracted from statute text | | EUR-Lex Integration | Automated metadata extraction |

As an EU member state, Croatia transposes EU directives into national law. This MCP server automatically detects and catalogues these cross-references, enabling bi-directional lookup between Croatian and EU legislation.

Data Sources & Freshness

All content is sourced from the authoritative Croatian legal database:

• Narodne novine (Official Gazette) -- Official Gazette of the Republic of Croatia
• EUR-Lex -- Official EU law database (cross-reference metadata)

Census-First Ingestion Pipeline

The ingestion pipeline follows the golden standard census-first approach:

1. Census (npm run census) -- Enumerates all Croatian laws from yearly CSV indexes (1990-present)
2. Ingest (npm run ingest) -- Fetches and parses each law from ELI endpoints
3. Build DB (npm run build:db) -- Compiles seed JSON into optimized SQLite

Automated Freshness Checks (Daily)

A daily GitHub Actions workflow monitors data sources:

| Source | Check | Method | |--------|-------|--------| | New legislation | Narodne novine CSV index | Yearly index comparison | | Portal availability | nn.hr HEAD request | Reachability check | | Database age | Build metadata | Flagged if >90 days old |

Security

This project uses multiple layers of automated security scanning:

| Scanner | What It Does | Schedule | |---------|-------------|----------| | CodeQL | Static analysis for security vulnerabilities | Weekly + PRs | | Semgrep | SAST scanning (OWASP top 10, secrets, TypeScript) | Every push | | Gitleaks | Secret detection across git history | Every push | | Trivy | CVE scanning on filesystem and npm dependencies | Daily |

See SECURITY.md for the full policy and vulnerability reporting.

Important Disclaimers

Legal Advice

THIS TOOL IS NOT LEGAL ADVICE

Statute text is sourced from official Narodne novine (Official Gazette) publications. However:

• This is a research tool, not a substitute for professional legal counsel
• Verify critical citations against primary sources for court filings
• EU cross-references are extracted from Croatian statute text, not EUR-Lex full text
• Coverage spans 1990-present but may not include the most recent amendments

Before using professionally, read: DISCLAIMER.md | PRIVACY.md

Client Confidentiality

Queries go through the Claude API. For privileged or confidential matters, use on-premise deployment. See PRIVACY.md for data handling guidance.

Development

Setup

git clone https://github.com/Ansvar-Systems/Croatian-law-mcp
cd Croatian-law-mcp
npm install
npm run build
npm test

Running Locally

npm run dev                                       # Start MCP server
npx @anthropic/mcp-inspector node dist/index.js   # Test with MCP Inspector

Data Management

npm run census                          # Enumerate all Croatian laws (census.json)
npm run ingest                          # Census-driven full ingestion
npm run ingest -- --resume              # Resume interrupted ingestion
npm run ingest -- --limit 10            # Test with 10 laws
npm run build:db                        # Rebuild SQLite database
npm run check-updates                   # Check for amendments
npm run verify:upstream                 # Verify provisions against source
npm run catalog:build-csv               # Build catalog from CSV indexes
npm run catalog:ingest                  # Ingest from catalog (incremental)
npm run catalog:sync-fast               # One-shot catalog + ingest

Performance

• Search Speed: <100ms for most FTS5 queries
• Database Size: ~253 MB (optimized SQLite with unicode61 tokenizer)
• Reliability: 99.7% ingestion success rate (4,531 of 4,529 ingestable laws)

Related Projects: Complete Compliance Suite

This server is part of Ansvar's Compliance Suite -- MCP servers that work together for end-to-end compliance coverage:

@ansvar/eu-regulations-mcp

Query 49 EU regulations directly from Claude -- GDPR, AI Act, DORA, NIS2, MiFID II, eIDAS, and more. Full regulatory text with article-level search. npx @ansvar/eu-regulations-mcp

@ansvar/swedish-law-mcp

Query 2,415 Swedish statutes directly from Claude -- DSL, BrB, ABL, MB, and more. Full provision text with EU cross-references. npx @ansvar/swedish-law-mcp

@ansvar/us-regulations-mcp

Query US federal and state compliance laws -- HIPAA, CCPA, SOX, GLBA, FERPA, and more. npm install @ansvar/us-regulations-mcp

@ansvar/security-controls-mcp

Query 261 security frameworks -- NIST CSF, ISO 27001, CIS Controls, SCF, and 1,451 mapped controls. npx @ansvar/security-controls-mcp

Contributing

Contributions welcome! See CONTRIBUTING.md for guidelines.

Priority areas:

• English translations for key statutes
• Historical statute versions and amendment tracking
• Case law integration
• Enhanced definition extraction

Citation

If you use this MCP server in academic research:

@software{croatian_law_mcp_2026,
  author = {Ansvar Systems AB},
  title = {Croatian Law MCP Server: Production-Grade Croatian Legal Research Tool},
  year = {2026},
  url = {https://github.com/Ansvar-Systems/Croatian-law-mcp},
  note = {Comprehensive Croatian legal database with 4,531 statutes and EU law cross-references}
}

License

Apache License 2.0. See LICENSE for details.

Data Licenses

• Statutes: Croatian Government Open Data (public domain under Copyright Act Art. 8)
• EU Metadata: EUR-Lex (EU public domain)

About Ansvar Systems

We build AI-accelerated compliance and legal research tools for the European market. This MCP server started as our internal reference tool for Croatian law -- turns out everyone building for the Croatian market has the same research frustrations.

So we're open-sourcing it. Navigating 4,531 statutes shouldn't require a law degree.

ansvar.eu -- Stockholm, Sweden