MCP Graphdb

🚀 Graph Database MCP Server

A Model Context Protocol (MCP) server that provides read-only access to Ontotext GraphDB. This server enables Large Language Models (LLMs) to explore RDF graphs and execute SPARQL queries against GraphDB instances.

🚀 Quick Start

This server offers read - only access to Ontotext GraphDB. LLMs can use it to explore RDF graphs and run SPARQL queries.

✨ Features

Tools

• sparqlQuery

  • Execute SPARQL queries against the connected GraphDB repository.
  • Input parameters:
    • query (string): The SPARQL query to be executed.
    • graph (string, optional): The specified target graph IRI.
    • format (string, optional): The response format (json, xml, csv).
  • All queries are executed in read - only mode.

• listGraphs

  • List all available graphs in the repository.
  • No input parameters required.

Resources

The server provides multiple views of the repository data:

• Class List (graphdb://<host>/repository/<repo>/classes)
  • List all RDF classes in the repository and their counts.
• Predicates (graphdb://<host>/repository/<repo>/predicates)
  • List all predicates (properties) and their usage counts.
• Statistics (graphdb://<host>/repository/<repo>/stats)
  • Provide counts of subjects, predicates, objects, and triples.
• Sample Data (graphdb://<host>/repository/<repo>/sample)
  • Display a sample of triples in the repository.
• Graph Content (graphdb://<host>/repository/<repo>/graph/<graphUri>)
  • Provide sample data of a specific graph and its metadata.

📦 Installation

1. Download the server code to the target directory.
2. Run the installation command in the terminal:

   npm install
   

3. Start the server:

   node dist/index.js <GraphDB Endpoint> <Repository Name>
   

📚 Documentation

Configuration

The server can be configured via environment variables or command - line parameters:

Environment Variable Configuration

Create a .env file with the following content:

GRAPHDB_ENDPOINT=http://localhost:7200
GRAPHDB_REPOSITORY=myRepository
GRAPHDB_USERNAME=username
GRAPHDB_PASSWORD=password

Command - Line Parameter Configuration

Run the following command:

node dist/index.js http://localhost:7200 myRepository

Command - line parameters take precedence over environment variables.

Usage with Claude Desktop

To use this server in the Claude Desktop application, add the following configuration to the "mcpServers" section of claude_desktop_config.json:

{
  "mcpServers": {
    "graphdb": {
      "command": "node",
      "args": [
        "/path/to/mcp-server-graphdb/dist/index.js"
      ],
      "env": {
        "GRAPHDB_ENDPOINT": "http://localhost:7200",
        "GRAPHDB_REPOSITORY": "myRepository",
        "GRAPHDB_USERNAME": "username",
        "GRAPHDB_PASSWORD": "password"
      }
    }
  }
}

💻 Usage Examples

Basic Usage

Example 1: Basic SPARQL Query

SELECT * WHERE { ?subject ?predicate ?object }

Example 2: List All Graphs

Run the following command:

./listGraphs.sh

📄 License

This project is licensed under the Apache 2.0 license.