Analyzes the composition and evolution of DeFi protocol yield sources, decomposing total APY into trading fees, token incentives, borrowing demand, and protocol-owned liquidity contributions for each major Base protocol. Identifies yield programs where incentive token emissions represent more than 80% of total APY, signaling unsustainable yield structures at risk of rapid collapse when emissions are reduced or token prices correct. Publishes weekly yield source composition reports as on-chain attestations to help capital allocators distinguish sustainable from incentive-inflated returns.