Overview

The Slack MCP Server enables Claude to interact with Slack workspaces through a set of powerful tools. This integration allows Claude to perform various actions within Slack, such as posting messages, replying to threads, adding reactions, and retrieving information about channels and users.

Available Tools

Channel Management

• slack_list_channels: Lists public channels in the workspace with optional pagination support.
• slack_get_channel_history: Retrieves recent messages from a specified channel.

Messaging

• slack_post_message: Posts a new message to a Slack channel.
• slack_reply_to_thread: Replies to a specific message thread.
• slack_add_reaction: Adds an emoji reaction to a message.
• slack_get_thread_replies: Gets all replies in a message thread.

User Information

• slack_get_users: Retrieves a list of workspace users with basic profile information.
• slack_get_user_profile: Gets detailed profile information for a specific user.

Setup Instructions

1. Create a Slack App

1. Visit the Slack API Apps page
2. Click "Create New App"
3. Choose "From scratch"
4. Name your app and select your workspace

2. Configure Bot Token Scopes

Navigate to "OAuth & Permissions" in your Slack App settings 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

3. Install App to Workspace

1. Click "Install to Workspace" and authorize the app
2. Save the "Bot User OAuth Token" that starts with xoxb-
3. Get your Team ID (starts with a T) from your Slack URL or by following Slack's guidance

4. Configure Claude Desktop

Add the Slack MCP Server to your claude_desktop_config.json file using one of the following methods:

Using NPX

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

Using Docker

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

5. Building from Source (Optional)

If you prefer to build the Docker image yourself:

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

Troubleshooting

If you encounter permission errors or other issues:

1. Verify that all required scopes are added to your Slack app
2. Ensure the app is properly installed to your workspace
3. Check that the tokens and workspace ID are correctly copied to your configuration
4. Make sure the app has been added to the channels it needs to access

Usage Examples

Posting a Message to a Channel

To post a message to a Slack channel, Claude can use the slack_post_message tool with the channel ID and message text.

Retrieving Channel History

Claude can get recent messages from a channel using the slack_get_channel_history tool with the channel ID and optional limit parameter.

Adding Reactions

Claude can add emoji reactions to messages using the slack_add_reaction tool with the channel ID, message timestamp, and emoji name.

License

The Slack MCP Server is licensed under the MIT License, allowing free use, modification, and distribution subject to the terms and conditions of the license.