# MailSentry

Real-time email verification: syntax, MX records and a live SMTP handshake tell you
whether an address can actually receive mail, before you send to it. No mail is ever sent
to the address being checked.

## For agents and developers

- [OpenAPI 3.1 spec](https://mailsentry.pro/openapi.json) ([YAML](https://mailsentry.pro/openapi.yaml))
- [MCP server](https://mailsentry.pro/mcp) — Streamable HTTP ([server card](https://mailsentry.pro/mcp/server-card))
- [Full agent reference](https://mailsentry.pro/llms.txt)
- [Authentication](https://mailsentry.pro/auth.md)
- [Pricing and quotas](https://mailsentry.pro/pricing.md)
- [Human docs and playground](https://mailsentry.pro/docs)

## The short version

```bash
curl https://mailsentry.pro/api/v1/verify \
  -H "Authorization: Bearer ms_YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"email":"name@example.com"}'
```

Branch on `result`: `safe` (deliverable), `risky` (catch-all, mailbox full or unknown) or
`invalid` (do not send).

Accounts are created at [/signup](https://mailsentry.pro/signup) — a web form, not an API.
A 7-day Starter trial starts automatically, no card required.