Agenta can be loaded as a forge mod (1.2.5-1.7.10), fabric mod (Legacy fabric and cursed legacy), java agent (classic-1.7.10), modloader mod (a1.2.4_01-1.5.2), bukkit plugin (b1.0-b1.8.1).
Different versions, 1 jar. The same jar will work on everything from classic to release 1.7.10
Throw Agenta in your mods folder and forget about it. Agenta takes care to interface with Minecraft as little as possible. Hence most mods should just work with it.
Restores sound to ancient versions of the game. Enjoy the game more or less as it was in 2010.
What obscure version will you test it on?
Load and saving support in classic versions that wouldn't be able to do so otherwise!
Fixes skins and caps in multiplayer. It also updates the authentication calls for beta and alpha versions of the game! You can load up agenta as a bukkit plugin to facilitate this!