A GraphQL document is only valid if when it contains an anonymous operation (the query short-hand) that it contains only that one operation definition.
LoneAnonymousOperation Class Documentation
Example #1
0
 private function anonNotAlone($line, $column)
 {
     return FormattedError::create(LoneAnonymousOperation::anonOperationNotAloneMessage(), [new SourceLocation($line, $column)]);
 }