Softens vanilla keepInventory, when on, players still drop 50% of items and 50% of XP on death, splitting the difference between full keep and full vanilla.
Vanilla keepInventory is binary: either you keep everything on death or you keep nothing. ConfiguredKeepInventory splits the difference, when the gamerule is on and a player dies, the plugin lets keepInventory keep the inventory, but then deliberately drops half of it (and half of the player's XP) at the death location anyway.
Designed for events where full vanilla loss is too punishing but full keep removes all stakes. Death still costs you something, but it's recoverable if you can fight your way back.
Items. The plugin walks the player's full inventory after the death event resolves. Each individual stack is rolled with a 50% chance to be added to the death drops and removed from the kept inventory. So on average you lose half your items, but it's per-stack random, sometimes a clean half, sometimes lopsided. Stacks are dropped whole; nothing is split mid-stack.
Experience. The plugin computes the player's total XP using the vanilla level/progress curves, drops an experience orb worth 50% of it at the death location, then resets the player and grants them back the other 50%. This gives a clean halving rather than vanilla's slightly weird "drop only what fits in seven orbs" rule for keepInventory deaths.
keepInventory is true on the death event. With the gamerule off, vanilla behaviour is unchanged.