Rook opens the possibility for users to earn from their orderflow. Users earn ROOK from orders routed through the Coordinator Contract, where Keepers (Solvers who are whitelisted with the Rook Protocol) compete for the right to fill transactions. Users receive 80% of this rook bid, and the orderbook is hosted off-chain. These keepers source liquidity from all existing sources, competing to give the user the best possible price. The protocol launched in late April and has processed over 300M in volume.
If integrated, MetaMask would allow for users to have gas free trades, with the only gas cost being the token approval contract, Rook is also non custodial. Rook currently offers limit order functionality and autofill, with more ordertypes being developed.
Documentation - docs .rook.fi
Large user analysis - twitter .com/Rook/status/1525208845240283141
Community - discord .gg/rook