What is Valimail used for?

Valimail is a DMARC tool, they can be setup by either adding a txt record or a CNAME to your DNS. DMARC is a very important step to email security as you need SPF and DKIM also in place. Every Cyber Insurance package I have looked over requires DMARC to be in place to prevent spoofing the domain.

valimail is for capturing and processing DMARC report emails in a central location so you don't have to manually review report emails.