When using a parent taskId with 'include_subtasks=true', the GET Task API does not return complete data for the subtasks associated with the parent task.
Most notably, the 'custom_fields' data is NULL. That is very frustrating and defeats the purpose. I might as well just feed all taskId values into their own calls instead of saving time using the parent taskId.
Further, I noticed other fields are also missing. When using a basic taskId query, you get time_estimate and time_spent. But if you use a parent taskId query, only one of those fields is returned for Subtasks.
Long story short, it just doesn't make any sense how ClickUp has decided what to return when using a parent taskId in conjunction with 'include_subtasks=true'.
It causes our developers to have to loop back into the API to get all relevant subtask metadata.