slack-mcp-server

Setup Guide

Prerequisites

• Node.js 20+
• Google Chrome (for token extraction)
• macOS (for Keychain storage - other platforms use file storage only)

Installation

1. Clone or Copy the Project

cd ~
git clone https://github.com/jtalk22/slack-mcp-server.git
# or if already exists:
cd ~/slack-mcp-server

2. Install Dependencies

npm install

2.5 Verify Install Path in a Clean Directory

tmpdir="$(mktemp -d)"
cd "$tmpdir"
npx -y @jtalk22/slack-mcp --version
npx -y @jtalk22/slack-mcp --help
npx -y @jtalk22/slack-mcp --doctor

Expected:

• --version and --help succeed.
• --doctor exits with one clear status:
  • 0 ready
  • 1 missing credentials
  • 2 invalid/expired credentials
  • 3 connectivity/runtime issue
• --status is read-only and never performs Chrome extraction.

3. Get Slack Tokens

Option A: Setup Wizard (recommended)

1. Open Chrome
2. Navigate to https://app.slack.com and log in
3. Run:

   npx -y @jtalk22/slack-mcp --setup
   

Option B: Automatic Extraction (repo clone workflow)

npm run tokens:auto

Option C: Manual Extraction

1. Open https://app.slack.com in Chrome
2. Press F12 to open DevTools
3. Go to Application → Cookies → https://app.slack.com
4. Find the cookie named d and copy its value (starts with xoxd-)
5. Go to Console and paste:

   JSON.parse(localStorage.localConfig_v2).teams[Object.keys(JSON.parse(localStorage.localConfig_v2).teams)[0]].token
   

6. Copy the result (starts with xoxc-)
7. Run:

   npm run tokens:refresh
   

   And paste both values when prompted.

4. Configure Claude Desktop (GUI App)

Edit ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "slack": {
      "command": "/opt/homebrew/bin/node",
      "args": ["/Users/YOUR_USERNAME/slack-mcp-server/src/server.js"],
      "env": {
        "SLACK_TOKEN": "xoxc-your-token-here",
        "SLACK_COOKIE": "xoxd-your-cookie-here",
        "PATH": "/opt/homebrew/bin:/usr/bin:/bin"
      }
    }
  }
}

Important:

• Replace YOUR_USERNAME with your actual username
• Copy tokens from ~/.slack-mcp-tokens.json into the env section
• Fully restart Claude Desktop (Cmd+Q, then reopen)

Verify it’s working: Check ~/Library/Logs/Claude/mcp-server-slack.log

5. Configure Claude Code (CLI)

Edit ~/.claude.json and add under mcpServers:

{
  "mcpServers": {
    "slack": {
      "type": "stdio",
      "command": "node",
      "args": ["/Users/YOUR_USERNAME/slack-mcp-server/src/server.js"],
      "env": {}
    }
  }
}

Claude Code reads tokens from ~/.slack-mcp-tokens.json automatically.

6. Restart Claude

The Slack tools will now be available in both Claude Desktop and Claude Code.

Verification

In Claude Code, try:

slack_health_check

You should see your username and team name.

Troubleshooting

“No credentials found”

Run npx -y @jtalk22/slack-mcp --doctor to confirm diagnostic code, then npx -y @jtalk22/slack-mcp --setup with Slack open in Chrome.

“invalid_auth” Error

Tokens have expired. Run npx -y @jtalk22/slack-mcp --doctor and follow the suggested next action.

MCP Server Not Loading

1. Check ~/.claude.json syntax
2. Verify the path to server.js is correct
3. Restart Claude Code

Chrome Extraction Fails

Make sure:

• Chrome is running (not just in dock)
• You have a Slack tab open (not the desktop app)
• You’re logged into Slack in that tab
• In Chrome menu, enable View > Developer > Allow JavaScript from Apple Events

This site is open source. Improve this page.