hey everyone, trying to access the sample endpoints but they aren't serving any data?

'<https://api.graph.cool/simple/v1/apollo-engine-demo-posts>'

query {
  allFiles {
    contentType
    createdAt
    id
    name
    secret
  }
}

{
  "data": {
    "allFiles": []
  }
}

try

query {
  allPosts {
    id
  }
}