Yes, The Sharptool is meant for dull but intact blades.
Not for blades that are cracked.
General power-tool safety guidance is clear: do not use a damaged tool or accessory.
If the blade is structurally damaged, sharpening won’t restore strength and can increase risk (vibration, breakage, unpredictable cutting).
Inspect the blade before sharpening. If it’s cracked/bent/missing teeth: discard and replace it.
If it’s dull: Keep on sharpening with 2 or 3 passes!