Postgres MCP server

This MCP server implementation provides a simple HTTP interface for PostgreSQL databases. You can execute read-only queries and explore database resources using the Model Control Protocol (MCP) standard.

Prerequisites

• Go 1.23.6 or later
• PostgreSQL database
• Git

Installation

Clone the repository and download dependencies:

git clone https://github.com/ipfans/postgres-mcp.git
cd postgres-mcp
go mod download

Configuration

You can configure the database connection in two ways:

Using Command-line Flags

go run cmd/postgres-mcp/main.go -db "postgres://user:password@localhost:5432/dbname"

Using Environment Variables

Create a .env file in the project root and add your database URL:

DATABASE_URL=postgres://user:password@localhost:5432/dbname

Usage

Starting the Server

Run the following command to start the server:

go run cmd/postgres-mcp/main.go

The server will start on port 8080 by default.

Interacting with MCP Endpoints

Listing Database Resources

To list available database resources:

POST http://localhost:8080/mcp
Content-Type: application/json

{
  "type": "function",
  "name": "resources"
}

Executing Read-Only Queries

To execute a SQL query (read-only):

POST http://localhost:8080/mcp
Content-Type: application/json

{
  "type": "function",
  "name": "query",
  "arguments": {
    "query": "SELECT * FROM your_table LIMIT 10"
  }
}

The server only allows read-only operations to protect your database from modifications through the MCP interface.

How to add this MCP server to Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > MCP and click "Add new global MCP server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "cursor-rules-mcp": {
            "command": "npx",
            "args": [
                "-y",
                "cursor-rules-mcp"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explictly ask the agent to use the tool by mentioning the tool name and describing what the function does.