What was the working title of the Pokémon project before it was renamed?

The Pokémon project originally had the working title Capsule Monsters.

Satoshi Tajiri and the Game Freak team used the name while developing the concept of collectible creatures that could be stored and released. The idea reflected monster-catching media and the capsule-like devices used to contain creatures in the planned game world.

The title was later changed because Capsule Monsters could not be trademarked. The project moved through shortened forms such as Capumon before becoming Pocket Monsters, or Pokémon in its internationally accented form.

The name change helped create the familiar brand. In Japan, the franchise remains officially associated with Pocket Monsters, while Pokémon became the globally recognized short form. The acute accent over the e was used internationally to guide pronunciation and distinguish the name.