Neo4j MCP Server

A Model Context Protocol server that exposes a Neo4j graph database as tools an AI agent can call. It serves the MCP protocol over HTTP, so it can be reached by any MCP client — including a Databricks Unity Catalog MCP connection.

Tools

Tool	Purpose
read_neo4j	Run a read-only Cypher query (MATCH / RETURN). Write keywords are rejected.
write_neo4j	Run a write Cypher query (CREATE / MERGE / SET / DELETE).

Requirements

• Node.js 20+
• A Neo4j database (e.g. Neo4j Aura)

Setup

npm install
cp .env.example .env      # then fill in your Neo4j credentials + a secret token
npm run build
npm start                 # serves on http://localhost:3000

Endpoints:

• GET /health — liveness check
• POST /mcp — the MCP endpoint (requires Authorization: Bearer <MCP_SECRET_TOKEN>)

Optional: npm run seed loads sample data into Neo4j.

Environment

See .env.example. Copy it to .env and fill in:

Variable	Description
NEO4J_URI	Bolt/Aura connection URI, e.g. neo4j+s://<id>.databases.neo4j.io
NEO4J_USERNAME	Neo4j username
NEO4J_PASSWORD	Neo4j password
PORT	HTTP port (default 3000)
MCP_SECRET_TOKEN	Bearer token clients must present on /mcp

.env is git-ignored. Never commit real credentials.

Exposing it to Databricks (or any remote client)

The server listens on localhost. To let a remote MCP client reach it during development, expose the port with a tunnel:

ngrok http 3000

Then register the public URL as a UC HTTP/MCP connection in Databricks, using Authorization: Bearer <MCP_SECRET_TOKEN>. For production, host the server on a reachable machine instead of a tunnel.

Project layout

neo4j-mcp-server/
├── src/
│   ├── index.ts   # the MCP server (tools + HTTP transport)
│   └── seed.ts    # optional sample-data seeder
├── package.json
├── tsconfig.json
├── .env.example
└── .gitignore