Email Inbox API + Sending by Sendmux

MCP server · by Sendmux

Communication npmPythonStreamable HTTP v2.2.0

AI email inbox and sending tools with attachments, search, live events, and webhooks.

View source ↗ Website ↗ Generate config for multiple servers More servers

Install

Pin version registry version 2.2.0

npm
npx -y sendmux-mcp

npm
npx -y sendmux-mcp@2.2.0

Python
uvx sendmux-mcp

Python
uvx sendmux-mcp@2.2.0

Streamable HTTP
https://mcp.sendmux.ai/mcp

Setup by client

Pick your client — the config below is generated for this server (both local and hosted-endpoint forms). Copy respects the “Pin version” switch above.

claude_desktop_config.json

{
  "mcpServers": {
    "sendmux-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "sendmux-mcp"
      ],
      "env": {
        "SENDMUX_MCP_SURFACES": "<YOUR_SENDMUX_MCP_SURFACES>",
        "SENDMUX_MAILBOX_API_KEY": "<YOUR_SENDMUX_MAILBOX_API_KEY>",
        "SENDMUX_MANAGEMENT_API_KEY": "<YOUR_SENDMUX_MANAGEMENT_API_KEY>",
        "SENDMUX_SENDING_API_KEY": "<YOUR_SENDMUX_SENDING_API_KEY>"
      }
    }
  }
}

{
  "mcpServers": {
    "sendmux-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "sendmux-mcp@2.2.0"
      ],
      "env": {
        "SENDMUX_MCP_SURFACES": "<YOUR_SENDMUX_MCP_SURFACES>",
        "SENDMUX_MAILBOX_API_KEY": "<YOUR_SENDMUX_MAILBOX_API_KEY>",
        "SENDMUX_MANAGEMENT_API_KEY": "<YOUR_SENDMUX_MANAGEMENT_API_KEY>",
        "SENDMUX_SENDING_API_KEY": "<YOUR_SENDMUX_SENDING_API_KEY>"
      }
    }
  }
}

Remote (hosted) endpoint

https://mcp.sendmux.ai/mcp

Claude Desktop: Settings → Connectors → Add custom connector, paste this URL.

Format verified against the official Claude Desktop docs ↗.

terminal

claude mcp add --env SENDMUX_MCP_SURFACES=<YOUR_SENDMUX_MCP_SURFACES> --env SENDMUX_MAILBOX_API_KEY=<YOUR_SENDMUX_MAILBOX_API_KEY> --env SENDMUX_MANAGEMENT_API_KEY=<YOUR_SENDMUX_MANAGEMENT_API_KEY> --env SENDMUX_SENDING_API_KEY=<YOUR_SENDMUX_SENDING_API_KEY> sendmux-mcp -- npx -y sendmux-mcp

claude mcp add --env SENDMUX_MCP_SURFACES=<YOUR_SENDMUX_MCP_SURFACES> --env SENDMUX_MAILBOX_API_KEY=<YOUR_SENDMUX_MAILBOX_API_KEY> --env SENDMUX_MANAGEMENT_API_KEY=<YOUR_SENDMUX_MANAGEMENT_API_KEY> --env SENDMUX_SENDING_API_KEY=<YOUR_SENDMUX_SENDING_API_KEY> sendmux-mcp -- npx -y sendmux-mcp@2.2.0

terminal

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

Format verified against the official Claude Code docs ↗.

.cursor/mcp.json

{
  "mcpServers": {
    "sendmux-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "sendmux-mcp"
      ],
      "env": {
        "SENDMUX_MCP_SURFACES": "<YOUR_SENDMUX_MCP_SURFACES>",
        "SENDMUX_MAILBOX_API_KEY": "<YOUR_SENDMUX_MAILBOX_API_KEY>",
        "SENDMUX_MANAGEMENT_API_KEY": "<YOUR_SENDMUX_MANAGEMENT_API_KEY>",
        "SENDMUX_SENDING_API_KEY": "<YOUR_SENDMUX_SENDING_API_KEY>"
      }
    }
  }
}

{
  "mcpServers": {
    "sendmux-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "sendmux-mcp@2.2.0"
      ],
      "env": {
        "SENDMUX_MCP_SURFACES": "<YOUR_SENDMUX_MCP_SURFACES>",
        "SENDMUX_MAILBOX_API_KEY": "<YOUR_SENDMUX_MAILBOX_API_KEY>",
        "SENDMUX_MANAGEMENT_API_KEY": "<YOUR_SENDMUX_MANAGEMENT_API_KEY>",
        "SENDMUX_SENDING_API_KEY": "<YOUR_SENDMUX_SENDING_API_KEY>"
      }
    }
  }
}

.cursor/mcp.json (hosted endpoint)

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

Format verified against the official Cursor docs ↗.

.vscode/mcp.json

{
  "servers": {
    "sendmux-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "sendmux-mcp"
      ],
      "env": {
        "SENDMUX_MCP_SURFACES": "<YOUR_SENDMUX_MCP_SURFACES>",
        "SENDMUX_MAILBOX_API_KEY": "<YOUR_SENDMUX_MAILBOX_API_KEY>",
        "SENDMUX_MANAGEMENT_API_KEY": "<YOUR_SENDMUX_MANAGEMENT_API_KEY>",
        "SENDMUX_SENDING_API_KEY": "<YOUR_SENDMUX_SENDING_API_KEY>"
      }
    }
  }
}

{
  "servers": {
    "sendmux-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "sendmux-mcp@2.2.0"
      ],
      "env": {
        "SENDMUX_MCP_SURFACES": "<YOUR_SENDMUX_MCP_SURFACES>",
        "SENDMUX_MAILBOX_API_KEY": "<YOUR_SENDMUX_MAILBOX_API_KEY>",
        "SENDMUX_MANAGEMENT_API_KEY": "<YOUR_SENDMUX_MANAGEMENT_API_KEY>",
        "SENDMUX_SENDING_API_KEY": "<YOUR_SENDMUX_SENDING_API_KEY>"
      }
    }
  }
}

.vscode/mcp.json (hosted endpoint)

{
  "servers": {
    "sendmux-mcp": {
      "type": "http",
      "url": "https://mcp.sendmux.ai/mcp"
    }
  }
}

Format verified against the official VS Code docs ↗.

mcp_config.json

{
  "mcpServers": {
    "sendmux-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "sendmux-mcp"
      ],
      "env": {
        "SENDMUX_MCP_SURFACES": "<YOUR_SENDMUX_MCP_SURFACES>",
        "SENDMUX_MAILBOX_API_KEY": "<YOUR_SENDMUX_MAILBOX_API_KEY>",
        "SENDMUX_MANAGEMENT_API_KEY": "<YOUR_SENDMUX_MANAGEMENT_API_KEY>",
        "SENDMUX_SENDING_API_KEY": "<YOUR_SENDMUX_SENDING_API_KEY>"
      }
    }
  }
}

{
  "mcpServers": {
    "sendmux-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "sendmux-mcp@2.2.0"
      ],
      "env": {
        "SENDMUX_MCP_SURFACES": "<YOUR_SENDMUX_MCP_SURFACES>",
        "SENDMUX_MAILBOX_API_KEY": "<YOUR_SENDMUX_MAILBOX_API_KEY>",
        "SENDMUX_MANAGEMENT_API_KEY": "<YOUR_SENDMUX_MANAGEMENT_API_KEY>",
        "SENDMUX_SENDING_API_KEY": "<YOUR_SENDMUX_SENDING_API_KEY>"
      }
    }
  }
}

mcp_config.json (hosted endpoint)

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

Format verified against the official Windsurf docs ↗.

Environment variables

Defined in the server's official registry manifest. Required secrets are shown as <YOUR_…> placeholders in the configs above.

SENDMUX_MCP_SURFACES required — Tool surfaces to run locally.
SENDMUX_MAILBOX_API_KEY required secret — Mailbox API key for Mailbox API and Sending API tools.
SENDMUX_MANAGEMENT_API_KEY required secret — Root API key for Management API tools.
SENDMUX_SENDING_API_KEY secret — Optional send-capable smx_mbx_ key or owner-approved smx_agent_ token for Sending API tools when it differs from the Mailbox API key.

GitHub

⭐ 65 stars · 最近更新于 15 天前 · MIT license

About this server

Sendmux SDKs 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…

Summary from the project README — github.com/Sendmux/sendmux-sdk

Distributed as npm, Python, Streamable HTTP, listed under Communication. Review our MCP security guide before granting access to real data.

Frequently asked questions

What does the Email Inbox API + Sending by Sendmux MCP server do?

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

Run the install command shown above, then paste the config for your client (Claude Desktop, Claude Code, Cursor, VS Code or Windsurf) into its MCP settings and restart the client.

Is Email Inbox API + Sending by Sendmux free to use?

The MCP server itself is free to install. The source is public on https://github.com/Sendmux/sendmux-sdk. Any third-party service it calls may require its own API key and account.

Which clients support Email Inbox API + Sending by Sendmux?

Any MCP-compatible client can use it, including Claude Desktop, Claude Code, Cursor, VS Code, Windsurf and custom agents.

Add this badge

Publish this server? Link back with a badge on your README or site — copy either snippet.

Markdown

[![Listed on MCPNav](https://mcpnav.net/badge/sendmux-mcp.svg)](https://mcpnav.net/server/sendmux-mcp/)

HTML

<a href="https://mcpnav.net/server/sendmux-mcp/"><img src="https://mcpnav.net/badge/sendmux-mcp.svg" alt="Listed on MCPNav" height="20"></a>