Hi,
Similar to this question: Items Query responding with error
I have the exact same error; for example (on version 2023-07)
query {
  boards (ids: 3553135069) {
    items {
      id
      name
      column_values {
        id
        title
        value
      }
    }
  }
}
Returns:
{
  "errors": [
    {
      "message": "Unexpected token 'u', \\"upstream r\\"... is not valid JSON",
      "stack": "SyntaxError: Unexpected token 'u', \\"upstream r\\"... is not valid JSON"
    }
  ]
}
This query just ran successfully this morning, 10 minutes later the same query doesn’t work.

