Neo4j Graph Database MCP Server

MCP Server Configuration

Add to .claude/settings.json:

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{
  "mcpServers": {
    "neo4j": {
      "command": "npx",
      "args": ["-y", "@neo4j/mcp-neo4j"],
      "env": {
        "NEO4J_URI": "bolt://localhost:7687",
        "NEO4J_USERNAME": "neo4j",
        "NEO4J_PASSWORD": "${NEO4J_PASSWORD}",
        "NEO4J_DATABASE": "neo4j"
      }
    }
  }
}

Available Tools

Tool	Description
get-schema	Retrieve the full graph schema (node labels, relationship types, properties)
run-cypher	Execute a Cypher query and return results
explain-query	Get the execution plan for a Cypher query
get-node-count	Count nodes by label
get-relationship-count	Count relationships by type

Common Cypher Patterns

Schema Exploration

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// List all node labels with counts
CALL db.labels() YIELD label
RETURN label, size((:` + label + `)) AS count
ORDER BY count DESC;

// List all relationship types
CALL db.relationshipTypes() YIELD relationshipType
RETURN relationshipType;

// Show property keys for a label
MATCH (n:User)
WITH n LIMIT 1
RETURN keys(n) AS properties;

Common Queries

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// Find shortest path between two nodes
MATCH path = shortestPath(
  (a:User {name: 'Alice'})-[*..6]-(b:User {name: 'Bob'})
)
RETURN path;

// Recommendation engine: users who liked similar items
MATCH (user:User {id: $userId})-[:LIKED]->(item:Item)<-[:LIKED]-(other:User)
WITH other, count(item) AS commonLikes
ORDER BY commonLikes DESC
LIMIT 10
MATCH (other)-[:LIKED]->(rec:Item)
WHERE NOT (user)-[:LIKED]->(rec)
RETURN rec.name, count(other) AS score
ORDER BY score DESC
LIMIT 5;

// Find circular dependencies
MATCH path = (n:Module)-[:DEPENDS_ON*2..5]->(n)
RETURN path;

Performance Tips

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// Create indexes for frequently queried properties
CREATE INDEX user_email FOR (u:User) ON (u.email);
CREATE INDEX item_name FOR (i:Item) ON (i.name);

// Use PROFILE to analyze query performance
PROFILE MATCH (u:User)-[:PURCHASED]->(p:Product)
WHERE u.country = 'US'
RETURN p.category, count(*) AS purchases
ORDER BY purchases DESC;

Setup

1. Install Neo4j: brew install neo4j (macOS) or use Docker:

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   docker run -d --name neo4j \
     -p 7474:7474 -p 7687:7687 \
     -e NEO4J_AUTH=neo4j/your-password \
     neo4j:latest

2. Set the NEO4J_PASSWORD environment variable
3. Add the MCP configuration to .claude/settings.json
4. Access Neo4j Browser at http://localhost:7474 for visual exploration

Security Notes

• Store database credentials in environment variables, never in settings.json directly
• Use a read-only user for exploration if you want to prevent accidental mutations
• The MCP server connects over Bolt protocol (encrypted by default in production)
• Consider using a dedicated database user with limited permissions for MCP access
• Avoid running DELETE or DETACH DELETE queries through MCP without careful review