X Mailer API

Finding the APIs

The list of our APIs, for programs that look for it, is at /.well-known/api-catalog, in the format of RFC 9727. It links each API to its OpenAPI description, /openapi.json, and to this page.

Buying: the checkout API

Send a POST to /api/checkout with a JSON body naming the plan, the option and the buyer’s email address. No key is needed.

curl -X POST https://xmailer.to/api/checkout \
  -H 'Content-Type: application/json' \
  -d '{"plan": "mailer", "option": "lifetime", "email": "you@example.com"}'

The answer holds an order number and the address of a payment page. Open that page to pay in crypto. Once the payment clears, we email the installer link and the licence, or the proxy details, to the address given.

{
  "orderId": "XM-0123456789ABCDEF",
  "invoiceUrl": "https://nowpayments.io/payment/?iid=..."
}

The plans and options you can name, as plan / option:

• mailer / lifetime: X Mailer — One-year licence, $75
• bundle / monthly: X Mailer + Proxy — The app, plus a first month rotating every 10 minutes, $120
• bundle / rotate-per-email: X Mailer + Proxy — The app, plus a first month rotating on every request, $199
• proxy / rotate-10min: Proxy only — Rotating every 10 minutes, $100
• proxy / rotate-per-email: Proxy only — Rotating on every request, $180

The price comes from that list. Anything price-like in the request is ignored.

For a proxy or bundle plan, you may also send whitelistIp: the internet address of the server that will connect through the proxy. Leave it out and we will ask you for it by email.

A request that fails comes back with a JSON body holding an error message: 400 when the request is wrong, 429 after ten attempts in an hour from one address (failed attempts count too), and 502 when the payment provider cannot be reached.

Reading the site as Markdown

Every page is also served as Markdown at its own address, to any client that sends Accept: text/markdown. Adding .md to the address does the same: /pricing.md, or /index.md for the home page.

curl -H 'Accept: text/markdown' https://xmailer.to/pricing

The index of every page and guide, each at its Markdown address, is /llms.txt.

In the browser: WebMCP tools

Every page registers these tools with WebMCP, for an AI agent working in the visitor’s browser:

• list_plans: every plan and option, with its price and what it includes.
• search_site: pages and guides that match a query.
• read_page: a page as Markdown.
• open_page: shows the visitor a page.
• start_checkout: the checkout API above. It creates a payment page; nothing is charged until the buyer pays there.

Questions

Write to support@xmailer.to and a real person replies, usually the same working day.