Slack

Use a Slack app when a Slack MCP integration asks for a Slack Client ID and Client Secret.

See Overview for prerequisites and secret-handling guidance.

Create The Slack App

Open the Slack app dashboard and click Create New App.
Choose From scratch, enter an app name, and select the workspace that should own the app.
Open Agents & AI Apps and turn on the Model Context Protocol feature.
Open OAuth & Permissions.
Under Redirect URLs, click Add New Redirect URL, paste the QuilrAI callback URL, and save.
Under User Token Scopes, add the scopes required by the Slack MCP tools you plan to enable.
If you also run an in-Slack bot experience, add those bot scopes separately under Bot Token Scopes. Slack MCP tool permissions are granted on the user token.
Open Basic Information.
Under App Credentials, copy the Client ID and Client Secret.
Paste those values into the QuilrAI manual OAuth setup screen, then click Connect and authorize Slack.

Slack MCP tool	User scopes
Search messages and channels	`search:read.public`, `search:read.private`, `search:read.mpim`, `search:read.im`
Search files	`search:read.files`
Read files	`files:read`
Search emoji	`emoji:read`
Search users	`search:read.users`
Send messages	`chat:write`
Read channels and threads	`channels:history`, `groups:history`, `mpim:history`, `im:history`
Create conversations or channels	`channels:write`, `groups:write`, `im:write`, `mpim:write`
Add reactions	`reactions:write`
Create or update canvases	`canvases:read`, `canvases:write`
Read user profile and email	`users:read`, `users:read.email`
List channel members	`channels:read`, `groups:read`, `mpim:read`

Use Client Secret, not Signing Secret. The signing secret is for verifying Slack events and is not used as the OAuth client secret.
Slack requires MCP clients to be backed by a registered Slack app. Only internal apps or Slack Marketplace-published apps can use MCP; unlisted apps cannot use MCP.
Slack's MCP server uses user tokens for tool access. Add only the scopes needed by the tools you enable in QuilrAI.
For a single internal workspace, the app can stay private to that workspace.
If the same Slack app must be installed across multiple workspaces, configure Slack app distribution before sharing the install flow.
Slack redirect URLs must match the URL used by the OAuth flow. If QuilrAI shows a new callback URL later, add it to Slack before reconnecting.

Error	Likely cause	Fix
`invalid_client` or `bad_client_secret`	Wrong Client ID, wrong secret, or the Slack Signing Secret pasted instead of the Client Secret.	Copy the Slack Client ID and Client Secret again, update QuilrAI, and retry.
Slack MCP access denied	The Slack app is not enabled for MCP, is not an internal or Marketplace-published app, or lacks required user-token scopes.	Turn on Model Context Protocol under Agents & AI Apps, confirm the app is eligible for MCP, add missing User Token Scopes, and reconnect.
`invalid_scope`	The Slack app does not include a user-token scope requested by the MCP integration.	Add the missing scope in OAuth & Permissions, save, and reconnect.