I am wondering if there is a difference between the description attribute and the instructions attribute. The docs seem to use them interchangeably.
Yes because description of task in prompt can get the job done, or an instruction in prompt can also get the job done.
Alternatively a prompt can have a description of a task + instruction on how to go about that task.
Description: Make a Population Chart
Instruction: Search past 100 years of population census data for x, and create the chart.