Maybe a mixture of both. Were they specific like he only wants one of these exact 5 toys? Or more generic suggestions like he's into cars, Elmo, etc where you could buy what you wanted to do with cars of Elmo? I know for me, I usually called the parents and asked them what sort of things they were into before I shopped. So to me as an attendee it would have been a help, although I certainly never would have done it as the party giver. If they were specific toys or items then I do think it's tacky (although still not as tacky as our relative I posted about that said, bring money, or bring money, because we don't want anything but money so don't bring anything else

)