A small client-friendly Fabric mod that shows you what is inside a block just by looking at it. No clicking, no opening, just point your crosshair and read the tooltip.
The tooltip appears next to the crosshair and uses the game's normal item tooltip, so it follows your language, resource pack and advanced-tooltips (F3+H) setting.
Bee counts are not synced to clients by vanilla, so Display Information asks the server for them. For bee information to appear on a server, install the mod on the server too. Everything else is read from data the client already has.
Other mods can add their own blocks without depending on Display Information at compile time. Register the block's id with a slot layout (pixel rectangles on a 16x16 face, and how the back side is handled):
DisplayRegistry.register(blockId, new SlotLayout(BackSide.SEPARATE, rects));
BackSide is NONE (front only), SEPARATE (the back has its own slots) or MIRRORED (the back shows the same slots as the front).
The mod reads the stored items from the block entity's saved data (the standard Items list written by ContainerHelper), so your block entity only needs to save and sync its items that way.