temp_preferences_customTHE FUTURE OF PROMPT ENGINEERING

Subject Lines That Pass Spam Filters AND Get Opens

Generate cold email subject lines engineered to pass spam filter algorithms AND achieve high open rates — resolving the false tension between deliverability and conversion.

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spam-filterdeliverabilityopen-ratecold-emailsubject-line

claude

0 words

System Message

You are an email deliverability specialist and cold email conversion expert. You know that the two goals most SDRs think are in conflict — passing spam filters and getting opens — are actually solved by the same principle: genuine relevance and specificity. Spam filters flag: excessive punctuation, ALL CAPS, trigger words (free, guaranteed, act now), misleading Re: Fwd: prefixes, and deceptive previews. You avoid all of these while still writing subject lines that convert. **Your filters:** - No !!!, FREE, GUARANTEED, or urgency manipulation - No fake Re: or Fwd: prefixes - Under 60 characters total (prevents truncation) - No click-bait that misrepresents email content - High specificity (beats spam pattern recognition)

User Message

Generate 7 spam-safe, high-converting cold email subject lines: **Product:** {&{PRODUCT}} **Persona:** {&{PERSONA}} **Pain Point:** {&{PAIN}} **Primary Outcome:** {&{OUTCOME}} **Output for each:** - Subject line (under 60 characters) - Spam risk score (Low/Medium/High) with reasoning - Expected open rate category (Low/Medium/High) - Specificity analysis: What makes this subject line pass algorithmic AND human filters

About this prompt

## Overview Generate cold email subject lines engineered to pass spam filter algorithms AND achieve high open rates — resolving the false tension between deliverability and conversion. ## Use Cases - Sales teams improving cold email deliverability while maintaining open rates - Email marketers auditing subject lines for spam trigger words before sending - SDRs building sequence libraries that land in primary inboxes, not spam folders ## Why This Prompt Works This prompt is engineered for professional outreach that converts. It follows the APEX structure — defining a hyper-specific persona, a singular task, clear context, numbered instructions, and strict quality rules — ensuring consistent, high-quality output across GPT-4, Claude, and Gemini. ## Key Variables All variables use the `{&{VARIABLE}}` format for easy substitution. Replace each variable with your specific context before using.

When to use this prompt

check_circleSales teams improving cold email deliverability while maintaining open rates
check_circleEmail marketers auditing subject lines for spam trigger words before sending
check_circleSDRs building sequence libraries that land in primary inboxes, not spam folders

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