Sendmux is an email API for AI agents and developers. Create programmable inboxes, send and receive email, parse inbound messages into structured JSON, route across providers, and automate email workflows.
Get a free email inbox API for AI agents.
| Need | Link |
|---|---|
| Get a free email inbox API for AI agents | myagent.mx |
| Learn about Sendmux | sendmux.ai |
| Use the product | app.sendmux.ai |
| Read the docs | sendmux.ai/docs |
| Install the CLI | Homebrew tap (brew install sendmux/tap/sendmux) |
| Browse all SDKs and tools | Sendmux SDK monorepo |
| Get support | Support policy |
| Report a vulnerability | Security policy |
| Language or tool | Package |
|---|---|
| TypeScript | @sendmux/sdk |
| Python | sendmux-sdk |
| Go | sendmux.ai/go/v3 |
| Rust | sendmux (cargo add sendmux) |
| PHP | sendmux/sdk |
| Ruby | sendmux-sdk |
| CLI | Homebrew or @sendmux/cli |
The SDK monorepo also contains focused packages for sending, mailbox, and management workflows.
| Framework | Integration | Install |
|---|---|---|
| Vercel AI SDK | @sendmux/ai-sdk provides tools for agent inboxes and sending |
npm install @sendmux/ai-sdk ai zod |
| LangChain | langchain-sendmux provides a Sendmux toolkit for agent inboxes and sending |
pip install langchain-sendmux |
| Surface | What it provides | Link |
|---|---|---|
| Model Context Protocol (MCP) | Hosted OAuth access and a local sendmux-mcp package for mailbox, management, and sending tools |
MCP docs |
| Agent2Agent (A2A) Protocol 1.0 | A hosted OAuth-protected HTTP+JSON agent for mailbox, management, and sending operations | A2A docs and Agent Card |
| Agent skills | Installable Sendmux workflows for coding agents | Sendmux skills |
Email platforms were built for people clicking send, not agents and product workflows that need to send, receive, route, and react to email from code.
Sendmux covers outbound delivery, programmable inboxes, provider routing, delivery monitoring, and workflow automation in the same workspace.
- Send and receive email. Send through API or SMTP, receive into programmable mailboxes, and manage product email workflows from the same workspace.
- Bring your providers. Connect Gmail, Outlook, SendGrid, Mailgun, Resend, Amazon SES, or any SMTP-compatible provider. Sendmux handles routing, failover, monitoring, and quota guardrails.
- Parse inbound email for agents. Incoming email becomes structured JSON, including the subject, body, attachments, headers, and metadata.
- Monitor delivery. Delivery logs, bounces, complaints, webhooks, and provider health monitoring show what happened and help teams respond quickly.
Organisation defaults live in this repository and apply to Sendmux repositories that do not define their own files.
- Read the contributing guidelines before opening a pull request.
- Use the issue templates so maintainers receive the details needed to triage quickly.
- Never paste API keys, passwords, tokens, webhook secrets, customer data, or private account details into GitHub.
- Report vulnerabilities through the security policy, not public issues.
