could there be a antispam gateway that replies to 'maybe'(as in spam, ham and maybe) mails with a temporary url that hosts a webform, before they reach the inbo

could there be a antispam gateway that replies to 'maybe'(as in spam, ham and maybe) mails with a temporary url that hosts a webform, before they reach the inbox? the webform could even limit message length, prevent attachments, be protected by akismet and so on. let the message from the form be actually relayed to the real mail server. and once the recipient replies, automatically whitelist that sender or possibly even the domain?