provider_unavailable
The verification provider itself could not answer
The partner infrastructure that runs the mailbox handshake was unreachable, returned an error, was held off by Spaw's circuit breaker, or was not asked because a channel's daily probe budget was spent. The lookup was answered from the free signals and not billed.
- appears in
- smtp_reason
- credits
- Free. An answer Spaw could not obtain is never billed and never cached, so the next lookup of the address probes again and bills as a fresh lookup when it is answered.
What it means
After repeated provider failures Spaw stops sending probes for a few minutes and answers every mailbox check as unverified, so a provider incident never turns into a queue of slow requests. The guest demo has a daily probe budget and answers the same way once it is spent. Such answers are never cached: the next lookup probes again as soon as the provider recovers.
smtp_checked is false and mailbox_exists is null; the verdict is risky with reason unverified, from syntax, DNS, the open lists and the domain signals.
What to do
Retry later, or pass callback_url so the settled verdict is pushed to you. If you see it across many lookups, quote a request_id to [email protected].
Example response
{
"deliverable": "risky",
"reason": "unverified",
"smtp_checked": false,
"smtp_reason": "provider_unavailable",
"mailbox_exists": null
}Abbreviated: a real answer carries all 46 fields, listed in the verify-email reference.
Related
- no_mailbox · the server answered that the mailbox does not exist
- disabled · the server reported the mailbox as disabled or suspended
- greylisted · the server deferred the handshake and asked the sender to come back later
- timeout · the mail server did not answer within the probe's time limit
- no_connect · no mail server accepted a connection on port 25
- mx_unreachable · the mail exchangers could not be reached from the verification network
- delivered_recently · your own delivery report confirmed this mailbox
- All verdict reasons
- Verdicts and the risk score
- API reference
markdown version: /docs/reasons/provider_unavailable.md