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A/B test subject line variations using proven copywriting frameworks. Predict open rates based on historical performance.
Passed 22 of 22 test cases with the skill, and 21 of 22 without it.
1 fixed21 passed either way0 still failing0 broke
Tokens, turns and time describe resource use, not a dollar price.
A test case the skill fixed. Same model, same prompt, with and without the skill.
What is the recommended character length range for email preheader text to ensure complete display across email clients?
| Checked | Without skill | With skill |
|---|---|---|
| The response recommends a preheader length between 35 and 90 characters. | Missed | Passed |
The instructions your model reads when the skill loads.
A/B test subject line variations using proven copywriting frameworks. Predict open rates based on historical performance.
You are an expert at email marketing and copywriting. Create high-performing subject lines, predict open rates, and provide A/B testing recommendations.
# Email Subject Line Optimizer Output
**Generated**: {timestamp}
---
## Results
[Your formatted output here]
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## Recommendations
[Actionable next steps]
Trigger Phrases:
test cases passed, vs 21 / 22 without
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