Agamemnon, in the play Agamemnon, speaks about his friendship with Odysseus beginning in line 988. He has just returned home from a ten year war with Troy. The war was begun because Paris of Troy had abducted Helen (the wife of his brother Menelaus).
When addressing his people (his military escort and the Chorus), Agamemnon states that of all of the men who seemed loyal and without envy were not, except Odysseus. Agamemnon goes on to state that he had asked Odysseus to sail with him. Although he did not want to, Odysseus sailed with his friend. Once at sail, Agamemnon states that Odysseus "was prepared to pull his weight for me." Essentially, Agamemnon is stating that Odysseus is a true and loyal friend to him.