GraphRAG MCP Server

A Model Context Protocol server for querying a hybrid graph and vector database system, combining Neo4j (graph database) and Qdrant (vector database) for powerful semantic and graph-based document retrieval.

Overview

GraphRAG MCP provides a seamless integration between large language models and a hybrid retrieval system that leverages the strengths of both graph databases (Neo4j) and vector databases (Qdrant). This enables:

Semantic search through document embeddings
Graph-based context expansion following relationships
Hybrid search combining vector similarity with graph relationships
Full integration with Claude and other LLMs through MCP

This project follows the Model Context Protocol specification, making it compatible with any MCP-enabled client.

Features

Semantic search using sentence embeddings and Qdrant
Graph-based context expansion using Neo4j
Hybrid search combining both approaches
MCP tools and resources for LLM integration
Full documentation of Neo4j schema and Qdrant collection information

Prerequisites

Python 3.12+
Neo4j running on localhost:7687 (default configuration)
Qdrant running on localhost:6333 (default configuration)
Document data indexed in both databases

Installation

Quick Start

Clone this repository:

git clone https://github.com/rileylemm/graphrag_mcp.git
cd graphrag_mcp

Install dependencies with uv:
```
uv install
```

Configure your database connections in the .env file:

# Neo4j Configuration
NEO4J_URI=bolt://localhost:7687
NEO4J_USER=neo4j
NEO4J_PASSWORD=password

# Qdrant Configuration
QDRANT_HOST=localhost
QDRANT_PORT=6333
QDRANT_COLLECTION=document_chunks

Run the server:
```
uv run main.py
```

Detailed Setup Guide

For a detailed guide on setting up the underlying hybrid database system, please refer to the companion repository: GraphRAG Hybrid Database

Setting up Neo4j and Qdrant

Install and start Neo4j:

# Using Docker
docker run \
  --name neo4j \
  -p 7474:7474 -p 7687:7687 \
  -e NEO4J_AUTH=neo4j/password \
  -v $HOME/neo4j/data:/data \
  -v $HOME/neo4j/logs:/logs \
  -v $HOME/neo4j/import:/import \
  -v $HOME/neo4j/plugins:/plugins \
  neo4j:latest

Install and start Qdrant:

# Using Docker
docker run -p 6333:6333 -p 6334:6334 \
  -v $HOME/qdrant/storage:/qdrant/storage \
  qdrant/qdrant

Indexing Documents

To index your documents in both databases, follow these steps:

Prepare your documents
Create embeddings using sentence-transformers
Store documents in Neo4j with relationship information
Store document chunk embeddings in Qdrant

Refer to the GraphRAG Hybrid Database repository for detailed indexing scripts and procedures.

Integration with MCP Clients

Claude Desktop / Cursor Integration

Make the run script executable:
```
chmod +x run_server.sh
```

Add the server to your MCP configuration file (~/.cursor/mcp.json or Claude Desktop equivalent):

{
  "mcpServers": {
    "GraphRAG": {
      "command": "/path/to/graphrag_mcp/run_server.sh",
      "args": []
    }
  }
}

Restart your MCP client (Cursor, Claude Desktop, etc.)

Usage

MCP Tools

This server provides the following tools for LLM use:

search_documentation - Search for information using semantic search

# Example usage in MCP context
result = search_documentation(
    query="How does graph context expansion work?",
    limit=5,
    category="technical"
)

hybrid_search - Search using both semantic and graph-based approaches

# Example usage in MCP context
result = hybrid_search(
    query="Vector similarity with graph relationships",
    limit=10,
    category=None,
    expand_context=True
)

MCP Resources

The server provides the following resources:

https://graphrag.db/schema/neo4j - Information about the Neo4j graph schema
https://graphrag.db/collection/qdrant - Information about the Qdrant vector collection

Troubleshooting

Connection issues: Ensure Neo4j and Qdrant are running and accessible
Empty results: Check that your document collection is properly indexed
Missing dependencies: Run uv install to ensure all packages are installed
Database authentication: Verify credentials in your .env file

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Attribution

If you use this MCP server or adapt it for your own purposes, please provide attribution to Riley Lemm and link back to this repository (https://github.com/rileylemm/graphrag_mcp).