I think this question is pretty much impossible to answer, because at no time did we exist in anything like our modern forms without some form of even primitive tool.
Because we had tools, we became weaker, giving up raw strength and speed for more flexibility and dexterity so we could better wield those tools and traverse more environments. Because we had tools to cut and dig with we lost claws and canines, along with any notion of respectable bite strength, gaining fingernails which are wonderful for manual dexterity and small precision work.
We are weak animals BECAUSE of tools, not the reverse. Tool use was massively influential in our evolution to the human animal of today.
Our natural habitat under the constraints of the OP would most likely be extinction. We’ve been making and using stone tools for over 2M years, and we’ve evolved significantly since then. In fact, if you take tool use out of the equation, we wouldn’t be humans. Even chimps make and use tools.