Slack MCP Server

Slack MCP Server

Give your AI agent full Slack access. No app registration, no admin approval, no OAuth. One command, 16 tools, works with any MCP client.

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

▶ Watch the demo — 7 scenarios, from 47 unreads to inbox zero, without opening Slack.

Ask your AI to catch you up on #engineering from the last 24 hours. Search for that deployment thread from last week. Find the printer admin PIN nobody can remember. Send a reply. All from your editor.

Interactive demo · Latest release

Why This Exists

Slack's official MCP server requires a registered app, admin approval, and doesn't work with Claude Code or GitHub Copilot due to OAuth/DCR incompatibility. Screenshotting messages is not a workflow.

This server uses your browser's session tokens instead. If you can see it in Slack, your AI agent can see it too. No app install, no scopes, no admin.

Stealth Mode: Session tokens leave zero footprint in your workspace admin panel. No bot user appears, no app install shows up, no audit trail. Your AI agent operates with the same invisibility as your browser tab.

Quick Start per Client

Add to ~/.claude.json or Claude Desktop settings:

{
  "mcpServers": {
    "slack": { "command": "npx", "args": ["-y", "@jtalk22/slack-mcp"] }
  }
}

Add to .cursor/mcp.json:

{
  "mcpServers": {
    "slack": { "command": "npx", "args": ["-y", "@jtalk22/slack-mcp"] }
  }
}

Add to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "slack": { "command": "npx", "args": ["-y", "@jtalk22/slack-mcp"] }
  }
}

Add to ~/.gemini/settings.json:

{
  "mcpServers": {
    "slack": { "command": "npx", "args": ["-y", "@jtalk22/slack-mcp"] }
  }
}

Add to ~/.codex/config.toml:

[mcp_servers.slack]
command = "npx"
args = ["-y", "@jtalk22/slack-mcp"]

Or via CLI: codex mcp add slack -- npx -y @jtalk22/slack-mcp

Tools

12 read-only, 4 write-path. All carry MCP safety annotations.

* slack_refresh_tokens modifies local token file only.

Install

Node.js 20+

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

The setup wizard handles token extraction and validation.

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

{
  "mcpServers": {
    "slack": {
      "command": "npx",
      "args": ["-y", "@jtalk22/slack-mcp"]
    }
  }
}

Edit %APPDATA%\Claude\claude_desktop_config.json:

{
  "mcpServers": {
    "slack": {
      "command": "npx",
      "args": ["-y", "@jtalk22/slack-mcp"],
      "env": {
        "SLACK_TOKEN": "xoxc-your-token",
        "SLACK_COOKIE": "xoxd-your-cookie"
      }
    }
  }
}

Windows/Linux users must provide tokens via env since auto-refresh is macOS-only.

Add to ~/.claude.json:

{
  "mcpServers": {
    "slack": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@jtalk22/slack-mcp"]
    }
  }
}

Any client that supports stdio MCP servers works. Add to your client's MCP config:

{
  "slack": {
    "command": "npx",
    "args": ["-y", "@jtalk22/slack-mcp"],
    "env": {
      "SLACK_TOKEN": "xoxc-your-token",
      "SLACK_COOKIE": "xoxd-your-cookie"
    }
  }
}

On macOS, tokens are auto-extracted from Chrome — env block is optional.

Hosted version with permanent OAuth tokens coming soon. See mcp.revasserlabs.com for updates.

docker pull ghcr.io/jtalk22/slack-mcp-server:latest

{
  "mcpServers": {
    "slack": {
      "command": "docker",
      "args": ["run", "-i", "--rm",
               "-v", "~/.slack-mcp-tokens.json:/root/.slack-mcp-tokens.json",
               "ghcr.io/jtalk22/slack-mcp-server"]
    }
  }
}

Restart your client after configuration. Full setup: docs/SETUP.md

How It Works

Session tokens (xoxc- + xoxd-) from your browser. If you can see it in Slack, this server can see it too.

Token persistence — four-layer fallback:

1. Environment variables (SLACK_TOKEN, SLACK_COOKIE)
2. Token file (~/.slack-mcp-tokens.json, chmod 600)
3. macOS Keychain (encrypted)
4. Chrome auto-extraction (macOS)

Tokens expire. The server notices before you do — proactive health monitoring, automatic refresh on macOS, warnings when tokens age out. File writes are atomic (temp file → chmod → rename) to prevent corruption. Concurrent refresh attempts are mutex-locked.

Hosted HTTP Mode

For remote MCP endpoints (Cloudflare Worker, VPS, etc.):

SLACK_TOKEN=xoxc-... \
SLACK_COOKIE=xoxd-... \
SLACK_MCP_HTTP_AUTH_TOKEN=change-this \
SLACK_MCP_HTTP_ALLOWED_ORIGINS=https://claude.ai \
node src/server-http.js

Details: docs/DEPLOYMENT-MODES.md

Troubleshooting

Tokens expired: Run npx -y @jtalk22/slack-mcp --setup or use slack_refresh_tokens (macOS).

DMs not showing: Use slack_list_conversations with discover_dms=true.

Client not seeing tools: Check JSON syntax in config, restart client fully.

More: docs/TROUBLESHOOTING.md

Docs

• Setup Guide
• API Reference
• Architecture
• Deployment Modes
• Use Case Recipes
• Troubleshooting
• Compatibility

Security

• Token files: chmod 600 (owner-only)
• macOS Keychain encrypted backup
• Web server binds to localhost only
• API keys: crypto.randomBytes
• See SECURITY.md

Contributing

PRs welcome. Run node --check on modified files before submitting.

License

MIT — See LICENSE

Disclaimer

Not affiliated with Slack Technologies, Inc. Uses browser session credentials — check your workspace's acceptable use policy.

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Hosted version with semantic search, AI summaries, and permanent OAuth — coming soon at mcp.revasserlabs.com