How to get previous and next entry using the native GraphQL API? How do I turn these Craft queries into a GraphQL one?

// entry.twig

entry.getPrev({ section: "contentHub" })
entry.getNext({ section: "contentHub" })


I want to get the previous and next entry using the current entry
So I'm wondering the same thing, I'm using CraftQL as I need to support mutations, and I am close with this - but I get an error if I try to use $id instead of a hard-wired Int (e.g. 99): 


query getEntryData($id: [Int]) {
  prevEntry: entry(prevSiblingOf: 99) {
    id
    title
    slug
    uri
  }
  nextEntry: entry(nextSiblingOf: 99) {
    id
    title
    slug
    uri
  }
  entryData: entry(section: investigations, id: $id) {
    id
    title
    slug
    uri
  }
}


I get the following error: 

"message": "Variable \"$id\" of type \"[Int]\" used in position expecting type \"Int\".",


BUT then if I pass the $id as Int (and not [Int]) it works. Can't explain the typing difference. 

query getEntryData($id: [Int], $sameId: Int) {

   prev:entry(prevSiblingOf: $sameId) {
    id
    title
    slug
    uri
  }
  next: entry(nextSiblingOf: $sameId) {
    id
    title
    slug
    uri
  }
  investigation: entry(section: investigations, id: $id) {
    id
    title
    slug
    uri
  }
}