Responses & Status Values

Every call returns JSON. The label field is the same wording you see in the app (for example Catch All). The machine value is status for verify and result for find.

Verify status values

status	Meaning
valid	Mailbox exists and accepts mail.
invalid	Mailbox does not exist or was rejected.
risky	Deliverable but low quality (a role account like info@, disposable, or a full inbox).
catch_all	The domain accepts everything, so this exact mailbox cannot be confirmed either way.
unknown	Could not be determined right now (greylisting, timeout, or throttled). Safe to retry later.
unverified	The engine is not configured. You will not see this in normal use.

Find result values

result	Meaning
found	An address was confirmed. It is in the email field.
not_found	The common name formats were tried, none were valid.
catch_all	The domain accepts everything, so no specific address can be pinned down.
unknown	Could not be determined right now (transient). Safe to retry later.
invalid_domain	The domain is not a real, mailable domain.
no_name	No first or last name was supplied.

The mx field

mx tells you the mail provider behind the domain:

Google, Microsoft, Mimecast, Proofpoint, Barracuda, Zoho, Other

It is null if the domain has no mail records. Microsoft domains are verified through Microsoft's login system, everything else over SMTP.

Retrying unknowns

unknown is transient, not a dead end. It usually means the mail server greylisted or throttled the check. Retrying the same address a little later often returns a clear answer. The bulk tools in the app do this automatically.