JFL: Lying is a server-side-optimized toolkit for sending fake world information to clients, such as glowing outlines or entities. This is done on the packet level, meaning no in-world mechanics or datapacks will be affected.
For some examples, see the following images. All are from server-side functionality of mods.
Where Is It, used to highlight search requests for players who don't have the mod client-side.
Lenient Death, used to highlight dropped items on death. The outline colours change based on the lifetime of the items.
Eye Spy, used to add information text to the spyglass HUD with a Text Display Entity. Also used to add block highlights for the ping system.
Adding completion timers above campfire items.
The Basics
TODO, just cover simple fire and forgets
Future Planned APIs
Features
While these are planned, currently it's of the case of "when I need it", so there's no milestones.
Block lies, including left and right click interactions and maintaining them on 'correction' by the server
Particle lies, including one off and maintained
Sound lies - mainly one off, will have to look into sound loops
