Discord’s invite codes are usually a string of length 10. Each server, can also have a vanity invite, which is a user defined string.

Besides this, no other code is a correct Discord Invite.

As such, Invitebot accepts only valid Invite codes, in both formats they appear:

Even though Invitebot will list your invites with numbers, they’re not a valid invite, and will throw an error when inputted instead of the correct invite.