---
search:
  tags:
    - Audience
    - POST
seo:
  description: >-
    Check addresses before mailing them: syntax, DNS routing (MX, an implicit
    MX, or a null MX… Reference for the POST /v1/preflight endpoint in the
    Norbelys API.
sidebar:
  label: >-
    Check addresses before mailing them: syntax, DNS routing (MX, an implicit
    MX, or a null MX

    that refuses all mail), and the workspace's suppressions and holds. Never a
    mailbox probe:

    nothing is sent to the addresses, and nothing is stored. A route the
    workspace's sending

    found in DNS within the last day is answered from that, as the sender reads
    it; any other is

    asked of DNS now, and a lookup DNS could not answer is `unknown`. In a
    test-mode workspace only

    the syntax is checked, as its sender does: its mail never leaves the fake
    transport.
  badge: POST
title: >-
  Check addresses before mailing them: syntax, DNS routing (MX, an implicit MX,
  or a null MX

  that refuses all mail), and the workspace's suppressions and holds. Never a
  mailbox probe:

  nothing is sent to the addresses, and nothing is stored. A route the
  workspace's sending

  found in DNS within the last day is answered from that, as the sender reads
  it; any other is

  asked of DNS now, and a lookup DNS could not answer is `unknown`. In a
  test-mode workspace only

  the syntax is checked, as its sender does: its mail never leaves the fake
  transport.
type: openapi-operation
---
`POST /v1/preflight`