Plans a free web tool built to bring in customers: picks the idea, checks it against the real buyer, estimates payback, decides where to ask for an email, scopes the first version and defines how to judge it. Covers calculators, checkers, generators, converters and lookups, including tools backed by a paid API. Use when someone says "we want a free tool for leads", "should we build a calculator", "engineering as marketing", "lead-gen tool ideas", "gate the results or not", or "our free tool gets traffic but no signups". Produces a decision memo and a one-page build spec, not the tool's code.
