Connect Slack MCP

Slack's official MCP server does not support automatic OAuth client registration, so connecting it is a specialization of adding an MCP server: a Slack admin creates or approves a Slack app, and you add that app's OAuth client credentials in OpenWorking. You do not need the old bot tokens (xoxb-… / xapp-…).

Steps

1. Ask a Slack admin to create or approve a Slack app for MCP access at the Slack API apps page.
2. Under OAuth & Permissions, add the redirect URL http://127.0.0.1:19876/mcp/oauth/callback and the User Token Scopes your team needs.
3. Install/approve the app, then copy the Client ID and Client Secret from Basic Information → App Credentials.
4. In OpenWorking, open the Config screen and add a custom MCP server with the OAuth credentials, pointed at https://mcp.slack.com/mcp.
5. Save and restart the session, then sign in to Slack when prompted.

{
  "mcp": {
    "slack": {
      "type": "remote",
      "url": "https://mcp.slack.com/mcp",
      "oauth": {
        "clientID": "...",
        "clientSecret": "...",
        "scopes": ["search:read.public", "channels:history", "users:read", "chat:write"]
      }
    }
  }
}

Common scopes

Start read-first, then add write scopes only if you want the agent to act in Slack:

• Read: search:read.public, search:read.private, channels:history, groups:history, users:read, channels:read
• Write: chat:write, reactions:write