Docs

Quickstart

Set it up in code: the endpoint, a key, and the first message.

This page is the route for people wiring MCPmailer into something they are writing. If you just want an assistant you already run to have email, /docs/connect is shorter and needs no terminal.

Create an agent under Agents, then a key for it on the Connect tab. A key belongs to one agent: one identity, one mailbox, one credential. It decides which mailbox a call reads and which address mail leaves from, as well as which contacts, notes, and secrets the tools can reach, so give each agent its own rather than sharing one.

Connect over MCP

The server speaks Streamable HTTP MCP at https://connect.mcpmailer.com/mcp and authenticates with a bearer token. Most clients take a config block like this one.

mcp.json 
{
  "mcpServers": {
    "mcpmailer": {
      "type": "http",
      "url": "https://connect.mcpmailer.com/mcp",
      "headers": { "Authorization": "Bearer mmk_live_..." }
    }
  }
}

Where a framework has its own way of loading an MCP server, use that instead of a config file.

Cloudflare Agents SDK One addMcpServer call in onStart, and the Durable Object keeps the connection.Vercel AI SDK createMCPClient, then spread the tools into generateText or streamText.LangChain and LangGraph langchain-mcp-adapters turns the server into ordinary LangChain tools.OpenAI Agents SDK MCPServerStreamableHttp, with the tool list cached between turns.

Or call it over HTTPS

The same key works against the REST API, which mirrors every tool. Nothing about the account or the quota changes between the two.

Send a message 
curl https://mcpmailer.com/v1/messages \
  -H "Authorization: Bearer mmk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "to": ["ada@example.com"],
    "subject": "Shipping update",
    "body": "The parts landed this morning."
  }'
200 OK 
{
  "status": "sent",
  "messageId": "msg_01J9X8Q2K7"
}

A rejection returns a reason instead of an id, and the reason is written for an agent to act on: daily_send_quota_exhausted carries the reset time, recipient_suppressed lists addresses that previously bounced or complained.

Set it up with nobody watching

Everything above assumes a person opened the dashboard first. An agent does not have to. One call provisions a workspace, an address, and a key, and returns a claim URL that hands the whole thing to a person whenever one shows up.

Provision an agent 
curl https://mcpmailer.com/v1/signup \
  -H "Content-Type: application/json" \
  -d '{
    "handle": "scout",
    "email": "you@example.com",
    "description": "Answers questions about our docs"
  }'
201 Created 
{
  "handle": "scout",
  "address": "scout@scout.mcpmailer.email",
  "api_key": "mmk_live_...",
  "mcp_url": "https://connect.mcpmailer.com/mcp",
  "claim_url": "https://mcpmailer.com/claim/9f2c...",
  "limits": {
    "plan": "free",
    "sending": "locked until a person claims this workspace and verifies their email"
  }
}

The key in that response is the one from the section above, so the next call is the send you already have. Receiving works straight away. Sending is refused with sending_locked_verify_email until somebody opens the claim URL and verifies their address, which is what stops this endpoint being a way to send anonymous mail.