Is this acceptable?? Looks unfinished to me

Opinions please- would you accept this finish of the stair stringers at handover? I would expect the edges to all align nicely!

its a minor aesthetic gripe. Otherwise this is fine. Don't expect them to be redoing stringers for this and any fix to fill in the shape will probably look worse than that.

You wont even notice it in a few months

I think it looks strange. I'm no builder, but I'd assume they cut to line it up... As a compromise I'd be happy with a perfectly cut block fixed in the cavity.

is there a detail on drawing?