One field, ten seconds. Nothing is sent and nothing is stored.
What you know
Reads the public DNS records for your domain. It does not send mail, log in to anything, or touch your mailbox.
The finding
Your domain has no SPF and no DMARC record.
✕SPFMissing. Nothing tells the receiving server which machines are allowed to send as you, so anyone can — and filters treat your real mail as suspect.
✓DKIMPresent and valid. Your mail is signed, which is the one thing you have going for you here.
✕DMARCMissing. Without it a receiving server has no instruction for what to do when a message fails, so it quietly decides for itself.
Nothing run yet
Three DNS records decide whether your quotes land in the inbox or the spam folder.