Sendmux

What is Sendmux?

Sendmux is an email API platform designed specifically for AI agents and autonomous systems. It provides infrastructure for agents to send and receive emails at scale, treating email communication as a programmable, reliable service rather than a manual process. The platform enables users to create dedicated agent inboxes, manage email routing through their own email providers, and implement automatic failover mechanisms to ensure delivery reliability. This makes it particularly suited for applications where AI systems need to maintain persistent email communication channels, handle incoming messages, and trigger automated responses. Key capabilities include multi-provider support, allowing users to route outbound emails through their preferred email services while maintaining control over their infrastructure. The automatic failover system helps prevent service disruptions by seamlessly switching between providers if one becomes unavailable. Sendmux serves developers and organizations building AI agents that require email as part of their core functionality—whether for customer communication, notification systems, or agent-to-human workflows. By abstracting email complexity into a standardized API, it allows developers to focus on agent logic rather than email infrastructure challenges. The platform addresses the growing need for reliable, programmatic email handling in AI applications where traditional email clients or simple SMTP solutions prove insufficient.