Whom did Shlomo send to Chiram?
Radak: He sent [the message in the coming verses] via Chiram's messengers.
Here, it says only that Shlomo asked Chiram for workers to cut trees. In Divrei ha'Yamim II, 2:2-9, he asked for a great amount, and that Chiram send the wood, and specified different kinds of wood, and asked for a Chacham to work with different metals and materials. This is not mentioned here! There Shlomo said that he will give 20,000 Korim of wheat and of barley for the workers. Here he promised to give whatever Chiram will request! Here, Shlomo said you know that no one knows how to cut trees like Tzidonim. In Divrei ha'Yamim II, 2:7, he said I know! Also Chiram's reply is different here and there!
Malbim: There were five messages. First Chiram sent to Shlomo to console him [over his father's death] and to strengthen the Bris and love with him. Then Shlomo sent to him and Chiram replied like it says here. After Chiram's reply, Shlomo sent to him like it says in Divrei ha'Yamim. There, Ezra completed what is omitted here. There was no need to repeat what was written here.