Subject Line Test Matrix

1Generate a subject line test matrix for one email — variants isolate ONE psychological lever each.
2
3INPUT:
4Email content summary: {{email_summary}} | Audience + relationship stage: {{audience}}
5Sender name options: {{senders}} | Past winners (optional): {{past_winners}}
6
7LEVERS (one variant per lever): curiosity_gap, specificity (number/detail), self_interest (clear benefit), urgency (only if real), social_proof, pattern_interrupt (unexpected format).
8PER VARIANT: subject (≤45 chars), preview text (≤80 chars, continues — never repeats — the subject), lever, risk note (spam-trigger words? overpromise?).
9RULES: The subject must be true to the email content — curiosity gaps that the email doesn't pay off destroy future opens. No ALL CAPS, no "RE:/FW:" fakery, emoji max 1 and only if brand-appropriate.
10
11OUTPUT — ONLY JSON: { "variants": [], "recommended_pair_for_ab": ["", ""], "why": "" }