I tried finding an answer to this question and didn't find anything that helped.
We had an instance where Man Overboard! was explored and the initial Check to Defeat (Dexterity 7) was failed. The card got played against a character who, on their turn, used the Masterwork Tools to auto-succeed at the Constutiton/Fortitude 7 check.
Here is what Man Overboard reads:
"At the start of each character's turn, the character next to this card must succeed at a Constitution or Fortitude 7 check to banish this card; otherwise, that character must bury the top card of his deck."
The question is if this Con/Fort 7 check is considered a "Check to Defeat" in which case the Tools would work. My initial thought was that it wasn't a check to defeat, but I could see an argument going either way.
It's not. Only whatever's in the "Check to Defeat" box is a check to defeat, so it's distinct from if it said "your check against a barrier."
I agree with Dave. The only time the rulebook uses the term "defeat" is in regard to overcoming a bane's Check To Defeat. The Con/Fort check to banish Man Overboard! isn't a check to defeat, it's a secondary check determined by the card.