How best can I use tags in URL for collection filters?

Hello,

I’m designing a set of collection filters for my theme, using clickable product tags. From what I see people use three ways of passing/reading parameters from URL:

/collections/frontpage?constraint=tag
/collections/frontpage?f=tag
/collections/frontpage/tag+tag

What would generally be the best/most recommended way?

Thanks,
Luca