Sendmux Email MCP

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

```json theme={null}
{
 "mcpServers": {
 "sendmux-docs": {
 "url": "https://sendmux.ai/docs/mcp"
 }
 }
}

 
 
 Add this server to your user or workspace `mcp.json`.

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

 
 
 Add this server to `~/.codex/config.toml` or a trusted project `.codex/config.toml`.

[mcp_servers.sendmux_docs]
url = "https://sendmux.ai/docs/mcp"

## MCP

MCP exposes the product surfaces you grant.

 Surface Use it for Access 
 Mailbox Search, read, organise, and send from granted mailboxes. Hosted grant with Mailbox access, an `smx_mbx_` key, or a scoped `smx_agent_` token locally 
 Management Manage team resources such as domains, mailboxes, sending accounts, logs, metrics, billing, and webhooks. Hosted grant with Management access, or an `smx_root_` key locally 
 Sending Send single or batch emails. Hosted grant with Sending access, an `smx_mbx_` key, or an owner-approved Sending-resource `smx_agent_` token locally 
 

 Hosted MCP is the default when your client supports remote MCP with browser OAuth. It keeps Sendmux in the authorisation flow, avoids distributing manual API keys to agents, and shows only the tools allowed by the grant.

 Setting Value 
 Server URL `https://mcp.sendmux.ai/mcp` 
 Authorisation server `https://app.sendmux.ai` 
 Health check `https://mcp.sendmux.ai/health` 
 

 Use the Postman collection when you want to test MCP requests from Postman:

 When you connect, Sendmux asks you to choose a team, product surfaces, and mailbox access where relevant. Access tokens are short-lived. Refresh tokens rotate on use and can last up to 30 days unless the connection is disconnected or expires.

 
 If you grant more than one mailbox, start mailbox workflows with
 `mailbox_list_granted_mailboxes` and pass the returned `mailbox_id` to tools
 that act on one mailbox.

## Connection modes

Use when your client can open a browser-based MCP OAuth flow.
 
 
 Use when your coding agent can launch a local command on your machine.
 
 
 Use when a client needs a URL but you run the MCP package yourself.

## Local package

Install the local package from PyPI:

 Run one surface:

 Run all product surfaces:

 The server validates key prefixes before starting. Management requires `smx_root_`. Sending accepts a send-capable `smx_mbx_` key or owner-approved Sending-resource `smx_agent_` token. Mailbox accepts an `smx_mbx_` key or a scoped `smx_agent_` token.

## Private HTTP

HTTP mode is useful when your MCP client connects to a server URL but you still want to run the package yourself.

 The endpoint defaults to `/mcp`. `/health` returns the selected surfaces. HTTP mode requires `SENDMUX_MCP_HTTP_BEARER_TOKEN` unless you explicitly start it with `--allow-unauthenticated-http`.

## Tool discovery

Tool names are generated from the current public API surfaces. Open your MCP client's tool picker after authorisation to see the tools available to that connection.
 Hosted connections show only the tools allowed by the selected product surfaces, permissions, and mailbox grant. Local servers show the tools for the surfaces and keys you provide at startup.

## Next steps

Configure Sendmux MCP in Claude Code, Cursor, Codex, Gemini CLI, Qwen Code, Zed, and more.
 
 
 Use package-managed clients from application code.
 
 
 Install the CLI with Snap, Homebrew, or npm when you need terminal access.
 
 
 Create scoped credentials for local MCP setups.

sendmux-mcp \
--surfaces mailbox,management,sending \
--mailbox-api-key smx_mbx_... \
--management-api-key smx_root_... \
--sending-api-key smx_mbx_...