📌Overview

Purpose: To enable integration between the MCP Server and Slack API for facilitating interactions in Slack workspaces.

Overview: The Slack MCP Server provides a set of tools that allows Claude to perform various actions within Slack channels, enhancing communication and collaboration in Slack workspaces.

Key Features:

Channel Management:
- slack_list_channels: List public channels for easy navigation and management.
- slack_get_channel_history: Retrieve recent messages from any channel, ensuring users stay updated on conversations.
Messaging Functionality:
- slack_post_message: Post messages directly to Slack channels, facilitating real-time communication.
- slack_reply_to_thread: Enable ongoing discussions by replying to specific message threads.
User Interaction:
- slack_get_users: Access a list of workspace users to identify and connect with team members.
- slack_get_user_profile: Obtain detailed profile information for individual users, enhancing user engagement.
Reactions and Feedback:
- slack_add_reaction: Add emoji reactions to messages, making interactions more expressive.
Thread Management:
- slack_get_thread_replies: Fetch all replies in a message thread to get a comprehensive understanding of discussions.

Slack MCP Server

MCP Server for the Slack API, enabling Claude to interact with Slack workspaces.

Tools

slack_list_channels
- List public or pre-defined channels in the workspace
- Optional inputs:
  - limit (number, default: 100, max: 200): Maximum number of channels to return
  - cursor (string): Pagination cursor for next page
- Returns: List of channels with their IDs and information
slack_post_message
- Post a new message to a Slack channel
- Required inputs:
  - channel_id (string): The ID of the channel to post to
  - text (string): The message text to post
- Returns: Message posting confirmation and timestamp
slack_reply_to_thread
- Reply to a specific message thread
- Required inputs:
  - channel_id (string): The channel containing the thread
  - thread_ts (string): Timestamp of the parent message
  - text (string): The reply text
- Returns: Reply confirmation and timestamp
slack_add_reaction
- Add an emoji reaction to a message
- Required inputs:
  - channel_id (string): The channel containing the message
  - timestamp (string): Message timestamp to react to
  - reaction (string): Emoji name without colons
- Returns: Reaction confirmation
slack_get_channel_history
- Get recent messages from a channel
- Required inputs:
  - channel_id (string): The channel ID
- Optional inputs:
  - limit (number, default: 10): Number of messages to retrieve
- Returns: List of messages with their content and metadata
slack_get_thread_replies
- Get all replies in a message thread
- Required inputs:
  - channel_id (string): The channel containing the thread
  - thread_ts (string): Timestamp of the parent message
- Returns: List of replies with their content and metadata
slack_get_users
- Get list of workspace users with basic profile information
- Optional inputs:
  - cursor (string): Pagination cursor for next page
  - limit (number, default: 100, max: 200): Maximum users to return
- Returns: List of users with their basic profiles
slack_get_user_profile
- Get detailed profile information for a specific user
- Required inputs:
  - user_id (string): The user's ID
- Returns: Detailed user profile information

Setup

Create a Slack App:
- Visit the Slack Apps page: https://api.slack.com/apps
- Click "Create New App"
- Choose "From scratch"
- Name your app and select your workspace
Configure Bot Token Scopes: Navigate to "OAuth & Permissions" and add these scopes:
- channels:history - View messages and other content in public channels
- channels:read - View basic channel information
- chat:write - Send messages as the app
- reactions:write - Add emoji reactions to messages
- users:read - View users and their basic information
- users.profile:read - View detailed profiles about users
Install App to Workspace:
- Click "Install to Workspace" and authorize the app
- Save the "Bot User OAuth Token" that starts with xoxb-
Get your Team ID (starts with a T) by following guidance here: https://slack.com/help/articles/221769328-Locate-your-Slack-URL-or-ID#find-your-workspace-or-org-id

Usage with Claude Desktop

Add the following to your claude_desktop_config.json:

npx

{
  "mcpServers": {
    "slack": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-slack"
      ],
      "env": {
        "SLACK_BOT_TOKEN": "xoxb-your-bot-token",
        "SLACK_TEAM_ID": "T01234567",
        "SLACK_CHANNEL_IDS": "C01234567, C76543210"
      }
    }
  }
}

docker

{
  "mcpServers": {
    "slack": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "-e",
        "SLACK_BOT_TOKEN",
        "-e",
        "SLACK_TEAM_ID",
        "-e",
        "SLACK_CHANNEL_IDS",
        "mcp/slack"
      ],
      "env": {
        "SLACK_BOT_TOKEN": "xoxb-your-bot-token",
        "SLACK_TEAM_ID": "T01234567",
        "SLACK_CHANNEL_IDS": "C01234567, C76543210"
      }
    }
  }
}

Environment Variables

SLACK_BOT_TOKEN: Required. The Bot User OAuth Token starting with xoxb-.
SLACK_TEAM_ID: Required. Your Slack workspace ID starting with T.
SLACK_CHANNEL_IDS: Optional. Comma-separated list of channel IDs to limit channel access (e.g., "C01234567, C76543210"). If not set, all public channels will be listed.

Troubleshooting

If you encounter permission errors, verify that:

All required scopes are added to your Slack app.
The app is properly installed to your workspace.
The tokens and workspace ID are correctly copied to your configuration.
The app has been added to the channels it needs to access.

Build

Docker build:

docker build -t mcp/slack -f src/slack/Dockerfile .

License

This MCP server is licensed under the MIT License. You are free to use, modify, and distribute the software, subject to the terms and conditions of the MIT License. See the LICENSE file in the project repository for details.