In response to these colonialist actions Kant mentions that the inhabitants of China and Japan had good reason to restrict the activities of Europeans allowing them only access but not entry with the Japanese allowing only the Dutch trading rights and keeping them entirely out of community with the natives. What is revealed by these comments, is how colonialism was grounded, in fact, on denial of a general community with those colonised where community should be understood in Gerry Cohen's sense of "justificatory community", i.e. a community composed of those who give and accept reasons against a common normative background.
The opening of this point about community gives a sense of what might be meant by "hospitality". If we take hospitality to involve some sense of justificatory community and hostility to indicate denial of any such then the general understanding of cosmopolitan right as based on conditions of universal hospitality would be indicative of cosmopolitan right as a specification of the formula of humanity from Kant's moral theory.
What further supports this reading of cosmopolitan right are Kant's concluding remarks concerning this 3rd definitive article. Here Kant states that the idea of cosmopolitan right is a "supplement to the unwritten code of the right of a state and the right of nations necessary for the sake of any public rights of human beings and so for perpetual peace" (Ak. 8: 360). Further Kant adds that it is only under this condition (of the third article) that we can flatter ourselves that we are constantly approaching perpetual peace.
These remarks indicate that the 3rd definitive article has a special place in Kant's discussion. Two curious things arise here. Firstly, in describing this third article as a supplement to the "unwritten code" Kant makes reference to the idea of supplement twice over. The "unwritten code" itself is presumably something over and above written codes and for it to have a supplement suggests a twofold addition to the written code. Secondly, if this condition is necessary for the sake of public rights of human beings the question arises as to the sense of its necessity. What makes it so necessary? Is it that only by means of it can a general approach be made towards overcoming the divisions between peoples? Or that what it guarantees (trade above all) is what would do this?