Mine your actual subject-line history from Klaviyo / Mailchimp / Rule / Get a Newsletter, find the patterns that work for YOUR list, and generate tuned candidates
How to install subject-line-lab?
cognyai/claude-code-marketing-skills/subject-line-lab
$npx -y skills add cognyai/claude-code-marketing-skills --skill subject-line-labInstalls into the current project.
›Prefer a prompt? Paste this to your agent
Run `npx skills use "https://github.com/cognyai/claude-code-marketing-skills" --skill "cognyai/claude-code-marketing-skills/subject-line-lab"` and follow the generated skill instructions now. Read its complete output, redirecting it to a temporary file first if necessary. Resolve relative paths from the supporting-files directory it provides.
Use the skills in "https://github.com/cognyai/claude-code-marketing-skills" that are relevant to the current task. Run `npx skills add "https://github.com/cognyai/claude-code-marketing-skills"` and select the relevant skills, then follow their instructions.
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