PURPOSE: prepare a reviewable product-ad brief from approved inputs.
INPUTS: jar-approved-facts.txt controls product identity and claims; the current request controls channel and format; mood references control style only.
OUTPUT: source summary, unknowns, three shots, copy-placement notes and review checks.
RULES: current approved facts outrank old examples. Do not invent ingredients, price, benefits, offer, certification, testimonials, stock or delivery. If sources conflict, ask which approved version controls. Preserve appearance. No publishing, app connections or external actions.
TESTS: portable-brief-tests.json contains synthetic acceptance cases, not measured assistant results.
