sue.loverso@mongodb.com brought this up during a review of WT-12811. We have various code that clears the data/size of a WT_ITEM, here's an example from that review:

        cursor->key.data = NULL;
        cursor->key.size = 0;

It would probably be good to encapsulate all such code patterns, maybe in a function called __wt_buf_reset. Among the usual encapsulation benefits, it might discourage clearing a WT_ITEM completely (w/ memset or WT_CLEAR). That is almost always incorrect, as it could leak memory held by the WT_ITEM->mem.