John Gill Commentary 2 Kings 13:12

"Now the rest of the acts of Joash, and all that he did, and his might wherewith he fought against Amaziah king of Judah, are they not written in the book of the chronicles of the kings of Israel?" — 2 Kings 13:12 (ASV)

And the rest of the acts of Joash, and all that he did
Though none of his acts as yet are recorded, but his sinful ones:

and his might ;
or valiant actions in war with the Syrians, (2 Kings 13:25) ,

and wherewith he fought against Amaziah king of Judah ;
of which there is an account in the following chapter:

are they not written in the book of the chronicles of the kings of
Israel ?
in the history of the transactions of their reigns.