The PostgreSQL MCP runs as a **local stdio server** connecting to your database: - **Read-Only Access**: By design, only SELECT queries are allowed—no INSERT, UPDATE, or DELETE - **Connection Credentials**: Your database connection string is stored locally - **Network Access**: The server connects to your database, which may be local or remote - **Query Logging**: Be aware that queries may be logged by your database server **Security best practices**: Use a dedicated read-only database user with minimal permissions, avoid exposing sensitive data columns, consider using a connection to a read replica rather than your primary database, and never expose production credentials unnecessarily.

To start using the PostgreSQL MCP: 1. **Create a read-only user** (recommended): ```sql CREATE USER mcp_readonly WITH PASSWORD 'secure_password'; GRANT CONNECT ON DATABASE your_db TO mcp_readonly; GRANT SELECT ON ALL TABLES IN SCHEMA public TO mcp_readonly; ``` 2. **Configure the connection**: Add the MCP with your connection string 3. **Add to your AI client**: Use `npx -y @modelcontextprotocol/server-postgres postgresql://user:pass@host:5432/db` 4. **Start querying**: Ask your AI questions about your data in natural language **Example**: "What are the top 10 customers by order value this month?"