Email Inbox API + Sending by Sendmux MCP Server

Official SDK, CLI, and MCP workspace for Sendmux. Product documentation: sendmux.ai/docs Management API reference: sendmux.ai/docs/api/introduction Mailbox API reference: sendmux.ai/docs/mailbox-api/introduction Sending API reference: sendmux.ai/docs/sending-api/introduction MCP guide: sendmux.ai/docs/guides/mcp

People connecting email tools to Claude, Cursor, VS Code, or another MCP client. The project is written in PHP.

VERIFIED ACTIVE

LAST COMMIT 2026-08-20 · ★ 78 · #9 OF 75 MAINTAINED EMAIL · VERIFIED 2026-08-25

MIT · PHP · how we verify → /methodology

01 · Install Email Inbox API + Sending by Sendmux

before you install - you'll need

The README does not document required environment variables for a basic install.

Claude Code

claude mcp add sendmux-sendmux-sdk --transport http https://mcp.sendmux.ai/mcp

Claude Desktop / Cursor / VS Code - add to config

{
  "mcpServers": {
    "sendmux-sendmux-sdk": {
      "url": "https://mcp.sendmux.ai/mcp"
    }
  }
}

Same JSON for Cursor. For VS Code, rename the top-level key from `mcpServers` to `servers`.

Using another client? Same JSON, different key

Claude Desktop · mcpServers

Cursor · mcpServers

VS Code · servers

Windsurf · mcpServers

Zed · context_servers

Cline · mcpServers

Roo Code · mcpServers

Continue · mcpServers

LibreChat · mcpServers

Gemini CLI · mcpServers

Codex CLI · mcp_servers

Full setup guides: every client.

02 · Evidence

https://mcp.sendmux.ai/mcp

transport: streamable-http

endpoint alive - authentication required · probed 2026-08-25

Security posture

What to check before giving this server access to your agent - from the registry, GitHub, and our own probes. We don't score safety; we show what's verifiable.

runs as local process (stdio) - runs on your machine with your user's permissions · remote - your agent's requests go to mcp.sendmux.ai

endpoint auth requires authentication - rejected our unauthenticated MCP initialize

license MIT - declared in the repository

pypi package sendmux-mcp - check the name against the project README before installing (PyPI has no namespace ownership)

registry namespace io.github.Sendmux is GitHub-verified and matches the repo owner

03 · What Email Inbox API + Sending by Sendmux can do

Prose above is summarized from the project's README and registry record - no invented capabilities.

Latest releases

ts-cli-v1.4.1 · 2026-08-19

1.4.1 (2026-08-19) · The following workspace dependencies were updated · @sendmux/sdk bumped to 1.4.1

ts-ai-sdk-v0.3.2 · 2026-08-19

0.3.2 (2026-08-07) · The following workspace dependencies were updated · @sendmux/mailbox bumped to 1.4.1

ts-sdk-v1.4.1 · 2026-08-19

1.4.1 (2026-08-19) · The following workspace dependencies were updated · @sendmux/mailbox bumped to 1.4.1

04 · Who maintains Email Inbox API + Sending by Sendmux

Email Inbox API + Sending by Sendmux is maintained by sendmux. It's the only MCP server we track from this author; the repo dates to May 2026.

05 · Facts

repository: github.com/sendmux/sendmux-sdk
website: https://sendmux.ai/docs/guides/mcp
category: email - ranked #9 of 75 actively-maintained email servers as of 2026-08-25.
release cadence: 10+ releases in the last 90 days (latest 2026-08-19)
registry: io.github.Sendmux/sendmux-mcp (active, first published 2026-06-19 · 10 versions)
packages: pypi:sendmux-mcp

06 · Email Inbox API + Sending by Sendmux FAQ

What is Email Inbox API + Sending by Sendmux?

Is Email Inbox API + Sending by Sendmux still maintained?

Yes - as of 2026-08-25, its last commit was 2026-08-20 and it shipped 10+ releases in the last 90 days. We re-verify nightly.

How do I install Email Inbox API + Sending by Sendmux?

Run `uvx sendmux-mcp`. The README does not document required environment variables for a basic install. You can also paste the ready-made client config above.

Does Email Inbox API + Sending by Sendmux require authentication?

Yes - when we probed the endpoint on 2026-08-25, it rejected an unauthenticated MCP initialize; you'll need credentials to connect.

07 · Alternatives to Email Inbox API + Sending by Sendmux

Alternatives to Email Inbox API + Sending by Sendmux

Maintained email servers if Email Inbox API + Sending by Sendmux isn't the fit.

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