Automate Your Cold Email Infrastructure with the Maildoso API and MCP

Everything in the sending lifecycle is an endpoint, from buying a domain to reading the reply. You can search available domains and register new ones (or connect domains you already own), provision and retire mailboxes at any scale with SPF, DKIM, and DMARC set for you, and export fresh mailboxes straight into your sequencer with no manual import. Beyond setup, you can route every reply into one unified inbox, manage warm-up services, and pull your usage and deliverability stats into your own dashboard or data warehouse.

Here's the full surface in one view:

The API docs cover request and response shapes for each one.

Authentication is a single Personal Access Token (PAT). No OAuth dance, no per-endpoint keys, no approval queue to wait through. You generate the token in app.maildoso.com under Settings → API Keys, treat it like a password, and add it as a Bearer header on every request. The same token works for both the REST API and the MCP server.

Going from zero to your first call takes three steps. Grab your token, confirm you're connected with a quick GET /v1/user/me, then start wiring up domains, mailboxes, and exports. A first call looks like this:

If that returns your account, you're ready to automate the rest. There's no SDK to install – if you can send an HTTP request from Shell, Node, Python, PHP, or Ruby, you can drive the whole platform.

Not everyone running outbound wants to write HTTP requests, and they don't have to. Maildoso ships a hosted MCP server, so you can connect it to an AI assistant and manage your setup in plain language. The agent calls the API for you.

Point your MCP client at mcp.maildoso.com/mcp with your token and you can type something like "Create 30 mailboxes across 6 domains for the Q3 campaign and export them to Smartlead," and it gets done – domains registered, mailboxes created with SPF/DKIM/DMARC, exported, and warming up. You can also ask operational questions like "Which domains are blocked right now?" and get a real answer with an offer to provision replacements. It works with Claude, Cursor, n8n, and any other MCP client, which means you can bake mailbox provisioning into an agent or workflow you already run.

On the sequencer side, the export endpoint pushes mailboxes directly into Instantly, Smartlead, Saleshandy, and other outreach platforms, replacing the export-CSV-then-import shuffle with one call. On the automation side, the MCP server plugs into Claude, Cursor, n8n, and similar clients, so Maildoso becomes a step in whatever stack your team already uses. Either way, the mailboxes arrive authenticated and ready, not as a raw list you still have to configure.

The clearest win is agency and high-volume provisioning. If you onboard a new client by standing up domains and mailboxes, the API turns a half-day of clicking into a single scripted run you trigger per client. Lead-gen teams scaling a campaign can provision hundreds of mailboxes in one request instead of batching by hand across days. Anyone rotating infrastructure to protect deliverability can retire and replace mailboxes programmatically on a schedule, rather than remembering to do it manually.

There's also a reporting angle that's easy to overlook. Pulling deliverability and usage stats through GET /v1/user/stats lets you keep the numbers where your team already works – your own dashboard, a spreadsheet, a warehouse – instead of logging into another tool to read them. For agencies reporting to clients, that means infrastructure health can sit right alongside campaign results.

The throughline is simple: the API removes the manual, repetitive setup work that doesn't scale, so the time you'd spend provisioning goes into the parts of outbound that actually move the number – targeting, copy, and follow-up.

If you want to try it, the fastest path is to generate a token, run the GET /v1/user/me call above to confirm you're connected, and read the API documentation for the endpoints you need. If you'd rather not touch code, connect the MCP server to your AI assistant and describe what you want in plain language. Both routes use the same single token, so you can start with one and move to the other whenever it makes sense.

Your copy and targeting only get you so far; the mailboxes you send from decide whether your emails actually land. On cold, misconfigured domains, even the best outreach ends up in spam. Maildoso supplies dedicated, warmed-up domains and mailboxes that get your messages in front of people, ready in about 3 minutes and starting at just $0.49 each.

And with Maildoso's API and MCP server, you can automate domain and mailbox provisioning and plug it straight into your existing stack and AI workflows.

API (REST API) – a set of HTTP endpoints that let you control Maildoso programmatically instead of through the dashboard.
MCP server – a hosted server that lets an AI assistant operate Maildoso through natural language, calling the API on your behalf.
Personal Access Token (PAT) – the single credential that authenticates both the REST API and the MCP server.
Sequencer export – pushing mailboxes directly into an outreach tool like Instantly or Smartlead via the API, with no CSV import.
Unified forwarding – routing every mailbox's replies into one inbox, with the original sending address restored when you reply.