He composed this for his pupil Ezra Abraham b. David Obadiah, because, the latter's time being devoted to physics and metaphysics, he could not enter deeply into the study of the Talmud (see introduction to Agur).
This practical consideration determined the form of the Agur, which contains only those rules that a layman should know, and comprises principally an abridged presentation of the material treated in the first and second parts of the Turim.
In the Agur, Landau gives excerpts from the halakhic literature which appeared after the time of Jacob ben Asher.
Although the Agur possesses little originality, it held an important position among law codes, and is often quoted, especially by Joseph Caro in the Shulchan Aruch.
At the end of the Agur, Landau gave a number of conundrums relating to halakhah, under the title "Sefer Chazon," which were afterward published separately (Venice, 1546; Prague, 1608).