Icons for custom geoprocessing tools - ArcGIS Pro

[JeremyGraham]

In ArcMap 10.X one could create and assign custom icons that could be added to the toolbar. In ArcGIS Pro there is nice ability to add custom tools/scripttools to the ribbon, however it seems that the ability to add the icons did not make it and the only option is the default scrollpaper icon. For those who often create customized tools for sponsors it would add a nice finishing touch.

[KoryKramer]

This is also logged with technical support as [ENH-000102786: Customize the Symbol used to represent a custom model in the Analysis Gallery].  If you prefer to track this through the ENH, you can contact support to get attached. 

The plan is to provide this functionality through setting the thumbnail in the tool's metadata - the thumbnail will be scaled to display in the analysis gallery and custom ribbon locations.