Individual skill

subject-lines

Writes and optimizes subject lines for cold emails. Use when the user asks to "write a subject line", "improve my subject line", "subject line ideas", "A/B test subject lines", "open rate optimization", "my open rates are low", or needs help with email subject lines specifically. Also triggers on "subject line best practices", "what subject line should I use". Do NOT use for writing full email body copy (use first-touch or follow-up), deliverability issues causing low opens, or newsletter subject lines.

master-skills/cold-email/.claude/skills/subject-lines/SKILL.md

Source commit 1a07684c9bb64a2ae696597de7ecd95dabef3adc

What was checked

Matches the observed repository HEAD

Yes

Scanner rules are current

Yes

Repository scan complete

No

Skill scan complete

No

Observed behavior

Network or broad shell

Last checked

Nov 11, 2026

These are observations at the recorded commit, not a guarantee of safety. Review the source before running it.

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