worms. good or bad?

would putting worms into the soil of your indoor plants be considered adding self generating organic soil or releasing the beast thats gunna destroy your roots?
i was wondering because as a kid my dad always used to tell me that they were good for your garden and helped your plants grow. would this also be true for an indoor marijuana grow?

I don't see why not

If you do that you'll have to feed them too.

what do worms eat? any idea what the worm to square foot of soil ratio should be?