Coding Assistants
Freemium
Sendmux
AI-optimized email API and routing platform for autonomous agents.
Quick Keypoints
- Strips signatures, quoted history, and code to clean JSON data for LLMs.
- Supports bring-your-own-provider settings for SES, Gmail, and SMTP.
- Implements granular API quota limits to protect LLM token budgets.
- Exposes signed webhooks and Server-Sent Events (SSE) for real-time routing.
What is Sendmux?
AI-optimized email API and routing platform for autonomous agents.
Sendmux is a unified email API built specifically for AI agents and developer workflows. It acts as an email inbox wrapper, automatically cleaning signatures, styling, and historical replies so that AI models only process raw JSON text, optimizing token efficiency and reducing parsing logic.
Who Needs Sendmux?
AI software engineers, chatbot builders, and developers building email integrations.
Primary Use Cases
- Cleaning inbound emails into token-efficient JSON for AI agents.
- Routing outbound transactional messages through custom email providers.
- Controlling LLM agent email access with granular quota limit structures.
Important Features
- BYO Infrastructure: Connects SES, Postmark, Google Workspace, and private relays.
- AI Parsing Layer: Strips formatting and headers to yield structured message objects.
- Agent Connectors: Features native MCP servers for Cursor and Claude integrations.
Current Updates About Sendmux
- Refined attachment handling via Model Context Protocol (MCP) and domain signing state tracking.
- Current Version: v1.0
Alternatives to Sendmux
If you want to check similar software, these alternative tools offer comparative features:
- Resend, SendGrid, Amazon SES
Pricing Plans
| Plan | Price |
|---|---|
| Free TierManaged SES capped at 50 outbound emails per day without credit card. | $0 |
| Standard Email APIUnified inbound and outbound email API using your own email provider. | $0.15 per 1k |
| Managed Amazon SESOutbound emailing through Sendmux's pre-configured SES integration. | $0.25 per 1k |
Affiliate & Referral Disclosure: We review products independently. Some of the outbound links on this directory are referral links containing tracking parameters. We may receive referral tracking credits or potential commission fees if you proceed to register or subscribe. Read our full Disclaimer.