Slack

Prerequisites

Create a Slack app and choose a workspace where it can access the channels and users needed by your SaaS. Add only the user permissions required for the tools you expose. Use the Web API reference, MCP app guide, and Slack app console.

Self-hosted setup

1. Create an internal or directory-published Slack app; unlisted external apps cannot use Slack MCP.
2. Enable Agents → Slack Model Context Protocol (MCP) Server for the app.
3. Add https://<your-authlane-host>/api/v1/oauth/slack/callback under OAuth redirect URLs.
4. Add the user-token scopes below, install the app, and copy its Client ID and Client Secret.

Configure authentication

Open Dashboard → Services → Slack → OAuth Configuration, enter the Client ID and Client Secret, save, and enable Slack. Authlane uses Slack's confidential user OAuth endpoints and PKCE-compatible flow so the resulting identity can be used by the official MCP server.

Scopes

• chat:write sends channel or direct messages.
• channels:read lists public channels visible to the connected app.
• channels:write creates public channels.
• users:read lists workspace users.
• users.profile:write updates the connected user's status.
• search:read.public lets Slack MCP discover public channels.
• search:read.users lets Slack MCP discover workspace users.

File upload is not exposed: Slack retired files.upload, and Authlane will not advertise a tool until the adapter implements Slack's current external upload flow.

Execution path

Prefer Slack's official MCP server at https://mcp.slack.com/mcp; follow the official Slack MCP documentation. Use the direct Web API adapter only for deterministic operations that the official server does not expose. The SaaS runtime—not Authlane—owns the MCP client and provider traffic.

Available tools

Messages

• slack_send_message

Channels and users

• slack_list_channels
• slack_create_channel
• slack_list_users

User status

• slack_set_status

Install @authlane/integration-slack in the SaaS runtime. A callback gets a fresh credential lease and calls Slack directly; messages, file content, and Slack responses do not pass through Authlane.

Connection lifecycle

Slack consent creates an encrypted connected connection. Authlane schedules background refresh only when Slack returns expiry and refresh material. Reconnect a connection that becomes expired or error after provider rejection. Disconnect through a new hosted session after recent user reauthentication.

Troubleshooting

• Channel listing and posting are limited to channels visible to the connected Slack app.
• File upload remains unavailable until the external upload flow is implemented end to end.
• Use channel and user IDs returned by Slack tools when names are ambiguous.