Add this MCP server to Claude Code.
Name: PostgreSQL MCP
Merge into: ~/.claude/mcp.json under mcpServers

---
{
  "mcpServers": {
    "postgres": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-postgres"],
      "env": {
        "POSTGRES_CONNECTION_STRING": "postgresql://user:password@localhost:5432/mydb"
      }
    }
  }
}

// ── Setup ────────────────────────────────────────────────────────────────────
// Replace the connection string with your actual database URL.
// The server is READ-ONLY by default — safe to point at production.
//
// For Supabase, use the Session Pooler URL (port 5432):
// postgresql://postgres.PROJECT_REF:PASSWORD@aws-X-REGION.pooler.supabase.com:5432/postgres
//
// ── Available tools ──────────────────────────────────────────────────────────
// query               execute a read-only SQL query
// list_tables         list all tables in the database
// describe_table      show columns, types, and constraints for a table