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post/email-preflight/v1/audit_html2 credits

Full pre-send structure + accessibility + deliverability lint of an HTML email: missing alt text, broken structure, mobile-width risks, dark-mode hints, tracking pixels, external assets, List-Unsubscribe check, Gmail-clip size budget, and prioritized recommendations. Pure local compute (no network).

Working example

Parameters

htmlrequired

The full HTML of the email you are about to send (paste the source). Parsed read-only in a no-network, no-script sandbox.

text_partoptional

Optional plain-text alternative of the email. If omitted, the audit flags the missing multipart/alternative text part.

base_urloptional

Optional base URL: relative links/images in the HTML are resolved against it before checking.

subjectoptional

Optional subject line — included in the spam-signal analysis.

check_linksoptional

If true, audit_html ALSO resolves every link via url-resolver (adds latency + a sub-call per link). Default false = static lint only.

request preview

curl -X POST https://api.reefapi.com/email-preflight/v1/audit_html \
  -H "x-api-key: $REEF_KEY" \
  -H "content-type: application/json" \
  -d '{"html":"<html><body><img src='https://x.test/a.png'><a href='https://x.test'>hi</a></body></html>"}'

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