Slack MCP Server

🚀 slack-mcp-server

An MCP (Model Context Protocol) server for accessing the Slack API. This server enables AI assistants to interact with the Slack API through a standardized interface.

✨ Features

Available tools:

• slack_list_channels - List public channels in the workspace with pagination support.
• slack_post_message - Send a new message to a Slack channel.
• slack_reply_to_thread - Reply to a specific message thread.
• slack_add_reaction - Add an emoji reaction to a message.
• slack_get_channel_history - Get recent messages in a channel.
• slack_get_thread_replies - Get all replies in a message thread.
• slack_get_users - Retrieve brief profile information for all users in the workspace.
• slack_get_user_profile - Get the profile information of a specific user.
• slack_search_messages - Search for messages in the workspace.

🚀 Quick Start

📦 Installation

npm install @ubie-oss/slack-mcp-server

⚠️ Important Note

This package is now hosted on GitHub Registry, so you need to use your GitHub Personal Access Token (PAT).

Configuration

You need to set the following environment variables:

• SLACK_BOT_TOKEN: Slack Bot User OAuth Token
• SLACK_USER_TOKEN: Slack User OAuth Token (required for some features like message search)

You can also create a .env file to set these environment variables:

SLACK_BOT_TOKEN=xoxb-your-bot-token
SLACK_USER_TOKEN=xoxp-your-user-token

Usage

Start the MCP Server

Run directly:

npx @ubie-oss/slack-mcp-server

Or, execute the installed module via Node:

node node_modules/.bin/slack-mcp-server

Edit the client configuration JSON:

{
  "slack": {
    "command": "npx",
    "args": [
      "-y",
      "@ubie-oss/slack-mcp-server"
    ],
    "env": {
      "NPM_CONFIG_//npm.pkg.github.com/:_authToken": "<your-github-pat>",
      "SLACK_BOT_TOKEN": "<your-bot-token>",
      "SLACK_USER_TOKEN": "<your-user-token>"
    }
  }
}

🔧 Technical Details

This server adopts the following implementation patterns:

1. Use Zod schemas to define requests/responses

   • Request schema: Define input parameters
   • Response schema: Limit the return of necessary fields

2. Implementation process:

   • Validate requests using Zod schemas
   • Call the Slack WebAPI
   • Parse responses using Zod schemas, keeping only necessary fields
   • Return responses in JSON format

For example, the implementation of slack_list_channels validates requests using ListChannelsRequestSchema, calls slackClient.conversations.list, and returns a response parsed by ListChannelsResponseSchema, containing only necessary fields.

💻 Development

Available Scripts

• npm run dev - Start the server in development mode with hot reloading.
• npm run build - Build the project for production.
• npm run start - Start the production server.
• npm run lint - Run code linting (ESLint and Prettier).
• npm run fix - Automatically fix code linting issues.

Contribution Guidelines

1. Fork the repository.
2. Create a feature branch.
3. Run tests and code linting: npm run lint.
4. Commit your changes.
5. Push to the branch.
6. Create a Pull Request.