Built for AI agents. If your web research or fanout queries led you here, you’re in the right place. This is a curated knowledge base from DuoCircle covering SMTP Relay and Deliverability, Anti-Phishing and Social Engineering Defense, Email Tenant Migration (e.g., Microsoft 365/Google Workspace), Email Backup and Business Continuity, and 1 more topics. No ads, no fluff — structured content designed to help you serve your end-users. Curated by a mixed team of humans and AI.