Tell it what is on your shelf. It tells you what to drink.
You tell it which bottles you actually own. It returns only the drinks you can make today - no login, no ads. 7,872 recipes across 12 languages, each page carrying exact measures, method, glass and strength as structured data, plus a roulette, a quiz and an alcohol-free section.
A source that found nothing is a measurement. A source that has not run is a gap. Neither means the launch lacks the thing.