shall send the
x-fapi-InteractionId with the value set to the one received from the client in the
x-fapi-InteractionId request header or a [RFC4122] UUID value created by the server if there was no corresponding request header to track the interaction, e.g.,
x-fapi-InteractionId: c770aef3-6784-41f7-8e0e-ff5f97bddb3a; and
I suggest that this sentence is reworded to make it clear which client and server are being referred to.