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Playground demo key · api.reefapi.com

post/email-health/v1/mta_sts1 credit

MTA-STS: the _mta-sts.<domain> TXT (id) plus the fetched https://mta-sts.<domain>/.well-known/mta-sts.txt policy (mode, mx[], max_age).

Working example

Parameters

domainrequired

The domain to inspect (a bare host like github.com; a full URL, a leading www., or a full email address are accepted and normalized to the registrable domain).

request preview

curl -X POST https://api.reefapi.com/email-health/v1/mta_sts \
  -H "x-api-key: $REEF_KEY" \
  -H "content-type: application/json" \
  -d '{"domain":"google.com"}'

Hit Send to run this endpoint live.