Before adding a custom domain to the link shortening service, it must meet a few basic requirements.
The domain must be registered and fully active, with access to its DNS settings. You need to be able to configure DNS records, typically by pointing the domain or subdomain to the service using A or CNAME records.
The domain should not be in use by another service that would conflict with link routing. It also must not already be connected to another account within the platform.
In addition, the domain should comply with general policies, such as not being blocked, restricted, or associated with prohibited content. Once these conditions are met and DNS changes have propagated, the domain can be successfully added and used for creating short links.