Slack MCP server

The Slack Model Context Protocol Server allows Claude Desktop (or any MCP client) to interact with your Slack workspace, enabling it to post messages and retrieve a list of all users.

Installation

Prerequisites

Before you begin, you'll need:

• Node.js installed on your system
• A Slack workspace with appropriate permissions
• Claude Desktop (or another MCP client)

Setting Up the MCP Server

1. Clone or download the MCP server repository
2. Install dependencies:

   npm install
   

3. Build the project:

   npm run build
   

Configuring Claude Desktop

Add the following configuration to your Claude Desktop MCP Server config file:

{
  "mcpServers": {
    "mcp-slack-local": {
      "command": "node",
      "args": ["/path/to/project/dist/index.js"],
      "env": {
        "SLACK_BOT_USER_OAUTH_TOKEN": "your-bot-token", 
        "SLACK_TEAM_ID": "your-team-id"
      }
    }
  }
}

Make sure to replace:

• /path/to/project/dist/index.js with the actual path to your project
• your-bot-token with your Slack Bot User OAuth Token
• your-team-id with your Slack Team ID

Usage

Running the Server

To start the MCP server:

node dist/index.js

For development with auto-rebuild:

npm run watch

Interacting with the Server

Once the server is running and properly configured with Claude Desktop, you can use these example prompts:

• "Can you list all users of my Slack team?"
• "Can you send a welcome message to my Slack Channel with the ID C12345678?"

Implemented Permissions

The MCP server currently implements the following Slack permissions:

• chat:write - Allows posting messages in approved channels & conversations
• users:read - Enables viewing people in a workspace

Troubleshooting

If you encounter issues:

1. Verify your Slack Bot User OAuth Token is valid
2. Ensure your Slack Team ID is correct
3. Check that the paths in your Claude Desktop configuration are accurate
4. Confirm that your Slack bot has the necessary permissions

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.