
Sendmux is an email inbox API for AI agents. It gives agents dedicated mailboxes, multi-provider sending, live inbox events, and developer tools so they can send, receive, route, and react to email in production.

Verified summary and editor assessment
Sendmux helps developers give AI agents a real email identity. Instead of stitching together a sending API, mailbox provider, parser, webhook layer, and billing system, teams can use one platform for inbound mailboxes, outbound sending, routing, quotas, webhooks, and live inbox events. Agents can receive email in dedicated mailboxes, read messages and threads, process attachments, send replies, and stream inbox activity through Server-Sent Events. Outbound sending supports SMTP, Gmail OAuth, Outlook OAuth, and Sendmux-managed Amazon SES, with delivery groups, weighted routing, per-provider quotas, health checks, and failover. Sendmux is built for AI agent teams, automation agencies, SaaS platforms, and developers building support agents, sales agents, scheduling agents, monitoring agents, and workflow agents. It also includes REST APIs, OpenAPI specs, SDKs, CLI, MCP tools, and Sendmux Skills. How To Use Create a Sendmux team, then create an agent mailbox using the included myagent.mx domain or a verified custom domain. Connect SMTP, Gmail OAuth, Outlook OAuth, or managed Amazon SES for outbound sending. Generate team-level or mailbox-scoped API keys, then use the API, SDKs, CLI, MCP, or Sendmux Skills to send, receive, route, and monitor email. Subscribe to webhooks or Server-Sent Events to watch live inbox and delivery events.
Sendmux stands out in the automation ecosystem for its balance of capability and accessible design. With an AIToolboard Score of 89/100, we recommend Sendmux for individuals and teams seeking efficient AI acceleration with low onboarding friction.
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Sendmux is a leading AI tool in the automation category designed to sendmux is an email inbox api for ai agents. it gives agents dedicated mailboxes, multi-provider sending, live inbox events, and developer tools so they can send, receive, route, and react to email in production..
Sendmux operates on a free pricing model. Check the official website for real-time tier options and enterprise volume discounts.
The best alternatives to Sendmux include Online Notepad, Floowed, aiFetchly. Each offers distinct features for automation workflows.
Yes, Sendmux holds an AIToolboard Enterprise Readiness score of 90/100, making it well-suited for individual creators, fast-growing startups, and corporate teams.
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