Determining cost basis and gift of equity for the assumption of a home loan by our daughter

My wife and I transferred the ownership of our home to my daughter and her husband in 2021 by allowing them to assume my VA loan.  The house was assessed by the city at $400,000. My cost basis was $250,000. The remaining loan amount was $210,000.  I am trying to determine if I have to file a gift tax return and what the "adjusted basis of gift" should be on the 709?  I was also wondering if my daughter's basis will be my basis or the loan amount?