Note:

This API is closed by default. To enable this interface, both the vm.estimateEnergy and vm.supportConstant configuration items must be activated simultaneously in the node configuration file.
estimateEnergy performs an estimation only; it does not generate an on-chain transaction or alter the current node's status. The energy_required field in its returned value represents the estimated energy amount, allowing the transaction's fee_limit to be set as energy_required X energy unit price.
While the triggerconstantcontract API is sufficient for estimating the energy consumption of calling most on-chain smart contracts (e.g., USDD, BTT, TUSD), the estimateEnergy API offers greater accuracy when estimating the energy consumption for a small number of special contracts. Furthermore, the energy estimate returned by estimateEnergy is guaranteed to be sufficient for setting the transaction's fee_limit.
Parameter encoding and decoding: Parameter and return value encoding and decoding

Returns

Field	Type	Description
result	Object	Result of the contract execution simulation.
result.result	bool	Whether the estimation was successful.
result.code	response_code(enum)	Response code indicating the error type. (Returned only on failure)
result.message	string	Response message describing the error details. (Returned only on failure)
energy_required	int64	Estimated Energy required to execute the transaction.