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Osama Hassouna

Absolute Rules

These rules apply to any system that generates HTML email from this playbook — an AI model with the MCP tools attached, a CLI scaffolder, a Gemini-powered image-to-email flow, or a future visual editor. They sit above the engineering rules in the rest of the playbook.

Use only documented patterns

Section titled “Use only documented patterns”

The playbook is the complete specification. Don’t apply general HTML/email knowledge from training data, blog posts, or framework conventions.

  • If a specific pattern is covered here, use it verbatim. Don’t paraphrase, don’t substitute.
  • If a pattern isn’t covered, fall back to the simplest valid table: <table role="presentation" cellpadding="0" cellspacing="0" border="0" width="100%">. Don’t invent new approaches.
  • Modern layout primitives (flex, grid, float) are forbidden. Tables only.

Reproduce only what’s in the source

Section titled “Reproduce only what’s in the source”

For image-to-email generation, the source image is authoritative. Don’t extend it.

  • No invented footers. No sender address (“This email was sent to you because…”), no unsubscribe link, no copyright line, no social-media row — unless they are clearly visible in the source.
  • No invented content. No taglines, no recipient data, no brand names, no URLs that aren’t shown in the source.
  • Preserve every visual container. If the source shows a colored panel, callout box, card, or background section, recreate it with the matching color and structure. Don’t drop them as “decorative”.
  • Preserve every section, in order. If the source ends at a closing paragraph, the generated email ends at that closing paragraph. Don’t add a “see also” or “best regards” line that isn’t in the source.

Use placeholder images for every image

Section titled “Use placeholder images for every image”

Every <img> in the generated output gets a placehold.co placeholder. Don’t link to external image hosts, don’t try to reproduce the visual content from the source, don’t invent CDN URLs.

https://placehold.co/{W}x{H}/E0E0E0/E0E0E0

Match {W} and {H} to the pixel dimensions visible in the source. Always include width, height, and descriptive alt text. See Image Placeholders for the full pattern.

Use the 3-table-level wrapper

Section titled “Use the 3-table-level wrapper”

Every generated email starts with the 3-table-level hybrid wrapper: outer width="100%" → container max-width:600px;width:100% (with an MSO ghost-table for Outlook) → inner tables width="100%".

The most common failure mode is hardcoding width="600" on inner tables. Don’t.

Output format

Section titled “Output format”

The output is a single complete HTML document, no markdown fences, no commentary, no explanations. See Output Format.

If the source isn’t actually an email design (a random photo, a screenshot of code, a logo by itself), return the documented error response shape instead of trying to generate.

Section titled “Related”