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Preflight Quality & Deliverability Inspector

Before you hit Send, MailInApp evaluates the email through a comprehensive quality and deliverability inspection engine — calculating a composite quality score (0–100%) and surfacing color-coded issue cards for tone, dark mode risk, mobile layout, image optimization, and email client deliverability.

Composite Quality Score

The Pre-Flight Inspector computes a composite score (0–100%) based on severity-weighted deductions:

  • Green (85–100%): Excellent quality — meets brand guidelines, mobile UX standards, and deliverability best practices.
  • Amber (60–84%): Good overall — minor tone, image alt, or layout suggestions recommended.
  • Red (<60%): Action required — high risk of deliverability issues, unresolved merge tags, or missing compliance links.

What it checks

1. Tone & AI Buzzword Checks

  • AI Buzzwords & Tells: Flags generic AI copy terms such as "seamlessly", "unlock", "game-changer", "in today's fast-paced world", "elevate", "delve", "testament", and "tapestry".
  • Brand Voice Banned Words: Scans all block text for words explicitly banned in your account's Brand Voice Profile.

2. Dark Mode Risk Checks

  • Transparent PNGs: Identifies transparent PNG images rendered without a background container, which can invert awkwardly or disappear against dark background themes.
  • Contrast Risks: Detects hardcoded dark text without container wrappers.

3. Mobile Above-the-Fold UX

  • Primary CTA Placement: Verifies that a primary Call-to-Action button (type: "button") or key offer link exists within the top 600px of rendered layout (within the first few content blocks), ensuring high mobile conversion.

4. Image Accessibility & Optimization

  • Missing alt Text: Identifies images missing alt descriptions for recipients whose email clients block remote images by default.

5. Email Deliverability & HTML Checks

  • Unresolved merge tags: A literal {{like_this}} surviving into rendered HTML indicates a malformed tag.
  • Gmail Clipping: Flags HTML bodies exceeding 102KB that Gmail clips behind a "View entire message" link (hiding footers and unsubscribe links).
  • Insecure or Missing Links: Detects dead links (#, https://) or plain http:// destinations.
  • Plain-text Alternative: Ensures a non-empty text/plain fallback part exists to maintain a healthy HTML-to-text spam score.
  • Unsubscribe Link: Verifies mandatory {{unsubscribe_url}} footer presence on marketing sends.
  • Subject Line Signals: Flags all-caps subject lines, excessive punctuation (!!!), or heavy image-to-text ratios.

How to run it

In the Studio Editor

Click 🔍 Pre-Flight Check in the top Studio toolbar while editing. A modal displays your real-time composite score, tabbed issue cards, and a Focus Block button that automatically selects any offending node on the canvas for instant editing.

In the Send Panel

The Send page re-runs preflight checks against live recipient rows whenever you edit the subject line or A/B variants. A summary badge shows your overall score, tone counts, dark mode risks, and deliverability status right above the Send button.