Humans can effortlessly use objects from their environment as tools. Even a human child can, not only recognize a fallen tree branch as a potential tool to reach a fruit on the tree, but also pick it up and immediately use it. It would be amazing if robots could do this as well- immediately recognize and use objects as tools for the benefit of a task. We propose a framework to enable similar abilities in robots. We first characterized human tools to identify a special category of tools that humans are able to use immediately through a process of skill transfer from their limbs, rather than tool learning. Motivated by the tool characterization and our neuroscientific studies on human tool use and embodiment, we then developed a tool cognition framework that enables a robot to recognize a previously unseen object as a tool for a task, plan the grasp and actions with the tool considering the task motions and obstacles, before finally performing the task with the tool. Furthermore, the framework allows for flexibility in tool use, where the same tool can be adapted for different tasks, and different tools for the same task, all without any prior learning or observation of tool use. In this talk I will briefly explain our tool cognition framework and show several robot experiments with both toy and real objects as tools.