t-morisawa/cc-slack-mcp-server

cc-slack

This is an MCP server for interacting with coding agents such as Claude Code via Slack.

Overview

This server provides integration with Slack using the Model Context Protocol (MCP). You can post questions from an MCP client (such as Claude Code or Continue.dev) to a specific Slack channel and receive responses from users. You can also continue the conversation in the same thread.

Features

• ask_user_via_slack: Posts a question to a specified Slack channel and waits for a reply in the thread
• Timeout: 30-minute timeout if no response is received

Slack App Configuration

1. Create an app at Slack API
2. Under Bot Token Scopes, add the following permissions:
   • chat:write
   • channels:read
   • channels:history
3. Enable Socket Mode and obtain an App-Level Token
4. Under Event Subscriptions, subscribe to the message.channels event
5. Add the app to the target channel

Installation & Startup

1. Install uv

# Mac/Linux
curl -LsSf https://astral.sh/uv/install.sh | sh
# Windows (PowerShell)
iwr -useb https://astral.sh/uv/install.ps1 | iex

2. Project Setup

# Create a virtual environment
uv venv

# Activate the virtual environment
# Mac/Linux:
source .venv/bin/activate
# Windows:
.venv\Scripts\activate

# Install dependencies
uv pip install -r requirements.txt

3. Set Environment Variables

Create a .env file in the project root and set the following variables:

SLACK_BOT_TOKEN=xoxb-your-bot-token
SLACK_APP_TOKEN=xapp-your-app-token
SLACK_CHANNEL_ID=C1234567890

4. Using with MCP Clients

Configure your MCP client (e.g., Claude Code or Continue.dev) as follows:

{
  "mcpServers": {
    "cc-slack": {
      "command": "uv",
      "args": ["run", "server.py"],
      "cwd": "/path/to/cc-slack-mcp-server"
    }
  }
}

To add the MCP server from the Claude Code command line:

claude mcp add cc-slack uv run /path/to/cc-slack-mcp-server/server.py

• cc-slack: Server name (arbitrary)
• uv run ...: Starts the server with automatic virtual environment and dependency resolution

After running this command, cc-slack will be added to the list of MCP servers in Claude Code, and MCP tools will be available.

Note: Since it is not possible to grant command permissions from Slack, it is recommended to run the server in a safe environment with auto-run or dangerously-skip-permissions mode enabled, so that the server does not prompt for command permissions.

5. Debugging

uv run mcp dev server.py

• Command: uv
• Arguments: run server.py