The Fox Spirit is a fox spirit who was recruited by The Rahjs to deliver a karma-infused crystaline lilly to The Party, as part of a deal made by Lord Kintamazu. They forbade her to speak to The Party while carrying out this task, so she delivered it by means of a mind-controlled courier, but she then met with them later, after her task had been completed. Spirits are good at looopholes.
She gave them The Pebble, instructing them that "when you get to the Feywild, please give this to The Tall One". Despite the fact that the Rahjs clearly didn't want her to talk to them and therefore probably didn't want this request carried out, The Party complied.
It is notable that when The Party met The Fox Spirit, they did not yet have any reason to think they would be visiting the Feywild, so it is possible that she has some degree of divination ability. It is also possible that she manipulated events so that they would be in the Feywild.