assets.installedTypes

The asset types installed in this world, the engine's own included.

Types are content: a world has the ones the engine ships and the ones it installed, and every other type is published content like any asset, found by searching for what you are making and installed with it. This lists the first group only, which is why its name says so.

Each row carries the type's name, the lead line of its own README, and whether it declares instantiate, the contract entityOps.fromAsset dispatches through, and therefore whether the type can become an entity in a scene.