Instead, an typically comes as a modified game client file (a single HTML file or a .epk file) with the textures pre-altered.
Here is a comprehensive guide on how these packs work and how to install them. eaglercraft xray texture pack
Most public Eaglercraft servers (like eaglercraft.com ) have anti-X-ray plugins. X-ray will only work on your own singleplayer world or on servers that lack anti-cheat. Instead, an typically comes as a modified game