newsletter-subject-lines

Installation
SKILL.md

Newsletter Subject Lines

Write subject lines that get opens.

Core Philosophy: 80% of email performance comes from the subject line. Generate 10+ options, evaluate systematically, select best.

Key constraint: 35-50 characters ideal (mobile preview). Be clear even when truncated.


The 3-Phase Workflow

Phase 1: Identify Core Value

What's the one thing that makes this newsletter worth opening?

Ask:

  • What's the most surprising insight?
  • What problem does this solve?
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Jan 27, 2026