Cook's mouse was described as dark gray above and lighter gray below in one published specimen. The Pakistan record is based on a single animal, and whether it represents a range extension remains unresolved.
In the single specimen collected in Pakistan, the fur was dark gray on the back and lighter gray underneath.
The paper reports one animal captured in a wheat field at a university research farm in Pakistan. This single record does not establish the species' usual habitat there.
An extinction-risk assessment has not been added yet.