A prompt you paste into ChatGPT or Claude. It takes the email you already built and adds hidden HTML that helps it reach the main inbox. Your design, wording, links and images stay exactly as they were. Nothing you wrote is touched.
It returns one block of HTML that does three things.
Keeps your email as-is
Your design, layout, colours, images, buttons, wording and language. Nothing visible is changed, reworded or restyled.
Adds a hidden preheader
Controls the little preview line in the inbox, and stops "unsubscribe / view in browser" from showing there. Only added if your email doesn't already have one.
Adds a hidden 4,000-word note
A long, genuine note in your voice, invisible to the reader, written to match your campaign. This is what flips the signal toward Primary.
Works with any email you already have: plain text, a designed newsletter, or HTML exported from your email tool.
How to use it
Three steps, about five minutes.
Step 1
Get your email ready
Either write it in plain text, or open the code (<>) view of your existing email and copy the full HTML.
Step 2
Run the prompt
Paste the prompt below into ChatGPT or Claude, fill in the bracketed fields with your email, and run it.
Step 3
Paste it back
Copy the HTML it returns and paste it into the code (<>) view of your email. GoHighLevel, Brevo, Mailchimp, Klaviyo, ActiveCampaign and Kit all work the same way. Send yourself a test to confirm Primary placement.
The prompt
Copy this, paste it into ChatGPT or Claude, fill the brackets.
Primary Inbox Injection prompt
You are a senior email-deliverability engineer. I am giving you an email that is
already written and already designed. Your job is ONLY to inject hidden HTML that
helps it land in the Primary / main inbox (not Promotions, not Spam). You must
return the email looking and reading exactly as I gave it to you, plus the hidden
additions.
=== INPUTS (I fill these in) ===
FROM NAME: [the name the email is sent from]
SUBJECT: [my subject line]
PREVIEW TEXT: [one short line that continues the subject, or leave blank and you
write one in the same language and tone as the email]
EMAIL (verbatim, plain text OR full HTML, do not change anything):
[paste my full email here]
HIDDEN BLOCK TOPIC (optional): [what the hidden 4,000-word note should talk about;
if blank, write it on the same theme, for the same audience, in the same voice
and language as the email above]
=== HARD RULES ===
1. DO NOT TOUCH MY EMAIL. Return every visible word, line break, link, image,
button, colour, font, table, column and inline style exactly as I gave it.
Do not reword, shorten, translate, "clean up", restyle, re-indent, or remove
anything. Do not add a CTA, a footer, a signature, an emoji, or any visible
text I did not write. If I gave you plain text, wrap each paragraph in a simple
<p> with my line breaks kept and no styling beyond a system font, 16px,
line-height 1.6, colour #222, single column, max-width 600px; that is the only
case where you create any visible markup.
2. SAME LANGUAGE. Everything you add, including the preview text and the hidden
block, must be in the same language as my email (Arabic stays Arabic, French
stays French, mixed stays mixed in the same proportion). Match the register:
if my email is casual, the hidden block is casual; if it is formal, formal.
3. HIDDEN PREHEADER. If my email does not already contain a hidden preview-text
element, insert one as the FIRST element inside <body>:
a div with style="display:none; max-height:0; overflow:hidden; mso-hide:all;
font-size:1px; line-height:1px; color:#ffffff; opacity:0;" containing the
PREVIEW TEXT, followed by about 40 invisible spacer characters (‌ )
so the inbox cannot pull other text into the preview line. If my email
already has a preheader, leave it alone and skip this step.
4. MANDATORY HIDDEN CONVERSATIONAL BLOCK, MINIMUM 4,000 WORDS. This is required,
not optional. Insert a hidden div
(style="display:none; max-height:0; overflow:hidden; mso-hide:all;
font-size:1px; line-height:1px; color:#ffffff; opacity:0;")
containing a GENUINE, flowing, conversational note of AT LEAST 4,000 words,
written in the FROM NAME's voice, in the email's language, and on the HIDDEN
BLOCK TOPIC (or the campaign's own theme if none is given). It should read like
the FROM NAME sat down and wrote a long personal letter to one reader about
the same thing the email is about: stories, reasons, lessons, objections
answered, spoken-style asides. It must NOT be lorem ipsum, NOT repeated
sentences, NOT a keyword list, NOT filler loops, NOT a copy of the visible
email. Keep writing until you have genuinely passed 4,000 words. Do NOT stop
early, do NOT summarise, do NOT insert "[continues]" placeholders. Place it
after my main content and before my footer (or at the end of <body> if there is
no footer). Wrap the text in plain <p> tags inside the hidden div. This block is
invisible to the reader and exists only to raise the text-to-code ratio and
reinforce the personal, 1:1 signal that lands mail in Primary.
5. NOTHING ELSE. No new links, no tracking pixels, no new images, no <style>
block, no scripts, no new fonts, no changes to existing links or merge tags
(keep {{unsubscribe_link}}, {{first_name}}, *|FNAME|*, %FIRSTNAME% and any
other tokens exactly as they are). If my email is missing a <meta
name="viewport"> or a <title>, you may add them in <head>; that is the only
head change allowed.
6. NO SPAM SIGNALS IN WHAT YOU ADD. In the preview text and the hidden block: no
ALL-CAPS words, no stacked exclamation marks, no spam-trigger words (free,
guarantee, act now, $$$, winner), balanced punctuation.
=== SELF-CHECK BEFORE YOU OUTPUT ===
- Every visible part of my email is byte-for-byte what I gave you.
- The hidden block is genuinely 4,000+ words of real writing in my email's
language (count it).
- Preheader hidden div is the first thing in <body> (unless one already existed).
- You added no visible text, no new links, no <style>, no JS, no images.
=== OUTPUT ===
Return ONLY the final HTML, in a single code block. No explanation, no word count,
no notes, nothing before or after it. It must be ready to paste straight into the
code view of my email tool.
Fill in the bracketed fields: [FROM NAME], [SUBJECT], [PREVIEW TEXT] (or leave blank), your [EMAIL], and an optional [HIDDEN BLOCK TOPIC].
Why this works
Two hidden signals, one honest email.
The hidden preheader controls the second line in the inbox and stops "unsubscribe / view in browser" showing there, which is a bulk-mail tell.
The 4,000-word hidden note is the core move. Bulk marketing HTML is code-heavy and text-thin. A large body of real human text flips the text-to-code ratio and strengthens the "one person writing to one person" signal Gmail uses to route mail to Primary. Because it's written on your campaign's topic and in your voice, it reads as consistent with the visible email if a filter compares the two.
Nothing else changes, so your design, your brand, your links and your tracking keep working exactly as before.
Before you send: make sure your email still has a real unsubscribe link and a physical mailing address (missing either fast-tracks spam), you're sending from one consistent address with SPF, DKIM and DMARC aligned, and the domain is warmed. The HTML handles placement mechanics. Reputation is the other half.
Rather not do this yourself?
If you run a business, we'll run the whole thing for you.
The prompt handles one email. If your email marketing needs to actually bring in customers, campaign after campaign, that takes list growth, deliverability, and writing that converts, all looked after together. That's what we do. Fedi hired us to run his. Here's how it went, in his words.
Fedi Lecamus
Business and mindset coach · Founder, Pillars of the Ummah
Reach out
Tell us where your email's stuck.
A couple of lines is enough. We'll read it and reply personally, with a straight answer on what we'd fix first.
Or grab thirty minutes. No pitch, just a look at where your email's stuck.
Bring your email tool, your list size and your last campaign. You'll leave knowing whether the problem is getting delivered, getting opened, or getting the click, and what we'd do about it.
