Glossary
Keeper
An incentivized bot that watches on-chain state and triggers time-sensitive contract actions — liquidations, vault harvests, or order fills — that no ordinary user will call voluntarily.
Many smart contracts expose functions that must be called at the right moment but that no ordinary user has an incentive to trigger: liquidating an unhealthy loan, harvesting vault yield, updating a price checkpoint, or executing a limit order once its condition is met. Because the EVM cannot schedule its own transactions, protocols rely on keepers — external bots that monitor state and send the call as soon as it becomes valid or profitable.
Keepers are paid through the action itself: a share of the liquidation bonus, a harvest fee, or a fixed reward. Networks such as Chainlink Automation, Gelato, and Keep3r formalize this market, matching jobs to a decentralized pool of bots so that critical upkeep does not depend on any single operator staying online.