Passing query variable to all subgraphs

Hi I am new to grqphql Federation. I have a use case where the query variables are required to resolve different features of an entity. For instance in the below schema both feature 1, feature 2 require the query variable deviceType in their resolvers. I am struggling to get the query variables in the service implementing subgraph 2. Thank you.

SubGraph 1 Schema

type Content @key(fields: "id"){

	getContent(String id, String deviceType) : [Content]

SubGraph 2 Schema

extend type Content @key(fields: "id"){
	id, @external