What part of the world is this spider in?
It is probably a spiderling, not an adult, probably a garden or orb species. It matters where in the world, if it is anywhere but North America I have no idea. It is doubtlessly beneficial, but watch out for webs during flower like dude said.
My best guess is Genus Argiope
https://en.wikipedia.org/wiki/Argiope_(spider)