Your summoned creatures, charmed minions, and hirelings have +4 to all ability scores, increased health (amount equal to what the Toughness feat would grant - total hit dice +2), and increased Fortification (+50%).
Notes
This includes Defender/Companion series (Iron, Mithral, Adamantine, Steel), Summon Monster 1-9, Nature's Ally 1-9, Pale Master skeletons, Drow Scorpion Faith, Charmed minions, Dominated minions, Hirelings, but not Hireling Summons Eg. A hireling sorcerer using Summon Monster I, the celestial dog would not be augmented.
Charmed or Dominated minions with Augment Summoning will also receive a bonus to saves from the ability score increase to escape the effect, but will lose bonuses from Augment Summoning once they do and can be re-Charmed or re-Dominated.
