A universal holder for the Silhouette Sketch Pens for use with the Cameo 5 in Tool Carriage 1 or 2.
For Cameo 4 there is a version that only fits in Carriage 1 and doesn't give you false hope it'll work in Carriage 2 otherwise identical.
 

My print profiles use the Support for PLA as the fitment is pretty important and will be hard to dial in otherwise.

A 14 mm x 10 mm piece of aluminium tape needs to be attached to the back for tool recognition to work.

It will be recognized as a Pen in Carriage 1 or a Pen Holder in Carriage 2.
Using Carriage 1 is faster than Carriage 2 but the results will be identical.

Some tuning of pressure might be required depending on the layer height and print quality.

Notes

Made with the personal version of Autodesk Fusion 360 therefore non commercial only.

Source file included.