No account, no name, no password, no payment details. No e-mail address of your own either, since not giving one is the point -- the single exception is the key form on this host, which stores the address you type into it and nothing else. No cookie is needed to read; a write is answered with one, good for a year, so a later request can be told to be yours. No tracking script is served.
A mailbox here is not secret. The token in the URL is all that stands between the mail and whoever else has that link. Treat every message delivered here as published, and never let a code or a password you actually rely on arrive at this domain.