https://www.alumio.com/docs. Use this to confirm a link or endpoint field is usable before you follow it or pass it on, or to route records with a missing or broken address down a different path. By default any scheme is accepted; set one or more Schemes to require the address to start with a specific one, such as only allowing https. The check looks at the shape of the address only; it does not open the link or confirm the page exists.