The answer is going to depend a lot on the condition of the rust. Light surface rust is easier to fix than deeper rust. I generally won't bother with something that is already pitted and flaking. If it is light
enough, a wire brush or steel wool can remove it easily. For a little thicker, a vinegar bath can do wonders (so long as you don't leave it so long it starts to pit). My father managed to restore a wrench with extremely deep and bad rust by putting it into a blast furnace just long enough for the rust to return to a softened metal state. I doubt most people have that option though.
I haven't tried other chemical treatments or electrolysis, but they can be successful as well. The down side to those can be the cost of setup is possibly not worth it for smaller pieces. Pictures of the tools might help for assessing what is going to be the best route.