ERICA Slack MCP Server

MCP server for accessing Slack private channels where the bot is a member.

Required Environment Variables

SLACK_BOT_TOKEN=xoxb-your-bot-token-here

How to Get the Bot Token

1. Go to Slack API Apps
2. Select your existing Slack app
3. Navigate to OAuth & Permissions in the sidebar
4. Copy the Bot User OAuth Token (starts with xoxb-)

Required Bot Token Scopes

Ensure your Slack app has these OAuth scopes under Bot Token Scopes:

| Scope | Purpose | |-------|---------| | channels:history | Read messages from public channels | | channels:read | List public channels | | groups:history | Read messages from private channels | | groups:read | List private channels | | chat:write | Post messages | | users:read | List users and get user info | | users:read.email | Access user email addresses | | search:read | Search messages (optional, requires user token) |

Note: For search:read to work, you may need a User OAuth Token instead of a Bot Token, as Slack's search API has limitations with bot tokens.

Tools

| Tool | Description | |------|-------------| | slack_list_channels | List all channels (public and private) where the bot is a member | | slack_get_channel_history | Get message history from a channel | | slack_get_thread | Get all replies in a thread | | slack_search_messages | Search messages across channels | | slack_post_message | Post a message to a channel | | slack_get_channel_info | Get detailed info about a channel | | slack_list_users | List workspace users | | slack_get_user_info | Get info about a specific user |

Installation

cd mcp/slack
npm install

Usage

The MCP server runs on stdio and is designed to be used with Claude Desktop or other MCP clients.

Claude Desktop Configuration

Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json):

{
  "mcpServers": {
    "slack": {
      "command": "node",
      "args": ["/path/to/ERICA/mcp/slack/index.js"],
      "env": {
        "SLACK_BOT_TOKEN": "xoxb-your-bot-token"
      }
    }
  }
}

Important Notes

• The bot must be invited to private channels to access them
• To invite the bot: In Slack, go to the private channel → Settings → Integrations → Add apps
• Message search may require a user token instead of bot token depending on your Slack workspace settings