You don't need an account, and this never signs you in here. Nothing you approve gives this site access to your website: any token your server issues is cancelled and thrown away when the check finishes.

What this is for

Apps that sign you in with your domain name often report nothing more useful than "login failed". The cause is usually one of a handful of things — your home page not naming a server, a server whose settings can't be read, or an address that doesn't quite match the one your server reports — and each of them looks identical from inside the app.

The page you get at the end has its own address, so you can send it to whoever runs your website or wrote the app you're trying to use. Secrets are hidden from it.

Building an IndieAuth server or app yourself? The server tests and client tests are far more thorough.