Contested Actions vs Mooks

Let’s say the GM created an NPC with some primary and secondary attributes, none of which includes logic. If a PC now gets into a battle of wits (e.g. some strategy game) with this guy, a contested action ensues with both participants using logic. Should the GM make up a seemingly fitting value for the NPC’s logic, or take 0? In other words: is the NPC quick build just an “incomplete” character creation, or is it more like a comprehensive list of all the attributes different from 0?

The NPC quick build guidelines are mostly in place for combat situations, so when I create encounters I only put points into the attributes of an NPC that I anticipate that will be needed or be relevant for that encounter. If that encounter goes differently than expected, than I’d say it’s perfectly acceptable for a GM to fill in the blanks of those NPCs, to flesh them out and adapt them for the arising situation. Obviously a GM should have a general idea of the characteristics of a NPC/monster, how they behave and would react, so that filling in those gaps is fairly easy on the fly.