# AnteHandlers The `x/feemarket` module provides `AnteDecorator`s that are recursively chained together into a single [`Antehandler`](https://github.com/cosmos/cosmos-sdk/blob/v0.43.0-alpha1/docs/architecture/adr-010-modular-antehandler.md). These decorators perform basic validity checks on an Ethereum or Cosmos SDK transaction, such that it could be thrown out of the transaction Mempool. Note that the `AnteHandler` is run for every transaction and called on both `CheckTx` and `DeliverTx`. ## Decorators ### `MinGasPriceDecorator` Rejects Cosmos SDK transactions with transaction fees lower than `MinGasPrice * GasLimit`. ### `EthMinGasPriceDecorator` Rejects EVM transactions with transactions fees lower than `MinGasPrice * GasLimit`. - For `LegacyTx` and `AccessListTx`, the `GasPrice * GasLimit` is used. - For EIP-1559 (*aka.* `DynamicFeeTx`), the `EffectivePrice * GasLimit` is used. ::: tip **Note**: For dynamic transactions, if the `feemarket` formula results in a `BaseFee` that lowers `EffectivePrice < MinGasPrices`, the users must increase the `GasTipCap` (priority fee) until `EffectivePrice > MinGasPrices`. Transactions with `MinGasPrices * GasLimit < transaction fee < EffectiveFee` are rejected by the `feemarket` `AnteHandle`. ::: ### `EthGasConsumeDecorator` Calculates the effective fees to deduct and the tx priority according to EIP-1559 spec, then deducts the fees and sets the tx priority in the response. ``` effectivePrice = min(baseFee + tipFeeCap, gasFeeCap) effectiveTipFee = effectivePrice - baseFee priority = effectiveTipFee / DefaultPriorityReduction ``` When there are multiple messages in the transaction, choose the lowest priority in them.