[loops-so skills, deliverability reference]: Avoid shortened youtu.be links: Gmail flags click-tracked short links as phishing (Loops Guardian warns on these); use the full youtube.com URL or disable tracking on the link. Send from a subdomain so the root-domain reputation stays safe. For new or weak domains, start with new signups and recently active users instead of blasting a cold audience, and verify the domain records on the sending-domain page in Loops before deeper troubleshooting. Loops recommends one sending domain per team; Gmail spam reports are not surfaced in Loops, so set up Google Postmaster for Gmail-specific reputation insight.

Context: Loops emails go to spam or trigger deliverability guardrails. Loops documents the copy and setup mistakes that hurt deliverability.