त्वं चाहं च मित्रं लभावहे इत्येवं आदिध् समसंधिः ॥ कZ_०७.९.०४ ॥
tvaṃ cāhaṃ ca mitraṃ labhāvahe ityevaṃ ādiḥ samasaṃdhiḥ
A treaty-opening framed as: 'You and I shall both gain a friend'—this is an equal (balanced) alliance.
Because the stated benefit is symmetric: both parties explicitly claim the same gain (acquiring an ally), implying parity in advantage and obligation.