Running into issues using Matter's slash commands in Slack? Occasionally, a workspace will find that Matter's slash commands don't appear at all, typing the command shows no suggestions, and nothing runs, even though everything else about Matter works. Matter can still post messages, and buttons on Matter messages still respond.
That "everything works except slash commands" pattern is expected with the causes below: in Slack, slash commands are registered and resolved separately from bot messages and button interactions.
This usually comes down to one of three causes on the Slack side:
A slash command conflicts with another app: If another installed app uses the same command name, Slack resolves the conflict to whichever app was installed most recently, so Matter's command can be silently hidden while the rest of Matter works normally.
The app isn't fully added to the workspace (Enterprise Grid): On Enterprise Grid, org-level approval and adding Matter to a specific workspace are separate steps. Slash commands only register in workspaces where Matter has actually been added; org approval alone isn't enough.
A stale install record in the workspace: In rare cases, a workspace's app install record holds onto outdated command registration state that doesn't clear with reauthorization; only a full remove and reinstall clears it.
Step 1: Check for a slash command conflict
Ask your Slack admin to review the workspace's installed apps for another app using the same command name as Matter.
If a conflicting app is found, remove it or coordinate with its owner — or remove and reinstall Matter so its commands take priority as the most recently installed app.
Helpful Slack documentation: Manage app approval for your workspace
Step 2: On Enterprise Grid, verify Matter is added to the workspace
If your company uses Slack Enterprise Grid, have an Org Owner or Org Admin confirm both of the following in the organization's admin dashboard:
Matter is approved/installed at the org level, and
Matter has been added to the specific workspace where the commands are failing
💡 A Workspace Admin can manage apps within their own workspace, but often can't see the org-level approval state. If your contact is a Workspace Admin, loop in an Org Owner or Org Admin to rule this out.
Helpful Slack documentation:
Step 3: Fully remove and reinstall Matter
If there's no command conflict and the workspace install checks out, the remaining cause is stale command registration state. Per Slack, there's no way to force slash commands to re-register on their own, and "Reinstall to Workspace" alone isn't sufficient. A full removal and reinstall of Matter is the reliable fix:
Remove Matter from the Slack workspace and reinstall Matter.
Test a Matter slash command.
Still not working?
Reach out to us at support@matterapp.com with:
Your Slack workspace Team ID
The exact command name(s) that aren't appearing
These two details are exactly what Slack support needs, so having them ready lets us escalate to Slack on your behalf without back-and-forth.