https://drafts.csswg.org/css-grid/#min-size-auto
The first paragraph ends with:
and which span at least one track whose min track sizing function is auto.
It's ambiguous if that means "in any axis" or "in the specified axis".
I suggest you append "in that axis" to the above sentence to make it unambiguous.
(The "whose overflow is visible" part is unambiguous by accident since visible in one axis implies it's visible in both axes.)