Python Toolbox Tool Parameter Hints

[RogerDunnGIS]

The tools that come with ArcGIS Pro have hints for each parameter.  Clicking the blue (i) symbol to the left of the parameter's name brings up a nice hint window.  (See Buffer > Side Type for an example).  I would like to create similar documentation for my Python Toolbox tools.  I cannot figure out which property of arcpy.Parameter to set for this.  Please explain how I should accomplish this.  Thank you.

[BlakeTerhune]

Try setIDMessage

Customize tool behavior in a Python toolbox—ArcGIS Pro | Documentation

[RogerDunnGIS]

I had seen these properties, but the documentation seems to indicate that they are for warning and error messages.  Thank you for posting, though.

[DanPatterson · Accepted solution]

I use custom python toolbox since you get validation code, visuals and a load more

Comparing custom and Python toolboxes—ArcGIS Pro | Documentation

I suspect you can edit the meta for a python toolbox as well

[RogerDunnGIS]

This will indeed work for me, but I didn't mark this as a solution.  Who did, and how did that happen?