Why do you think the Mayans created a codex?

The Maya developed their huun-paper around the 5th century, which is roughly the same time that the codex became predominant over the scroll in the Roman world. Maya paper was more durable and a better writing surface than papyrus. This codex deals primarily with astronomy: days, calendars, good days for rituals, planting, prophecies, etc

It was drawn by no fewer than eight different scribes and it is believed that it was created sometime between 1000 and 1200 A. D. during the Postclassic Maya period. This codex deals primarily with astronomy: days, calendars, good days for rituals, planting, prophecies, etc