Understanding the Inner Workings of eth_estimateGas in Smart Contracts

I'm seeking clarification on how the eth_estimateGas
function operates under the hood. Does it run the smart contract in a manner similar to a dry run?

When I make a call to eth_estimateGas
, and I've intentionally hardcoded a failed require
statement within the contract, I get this error in the response. This behavior suggests that the function might execute the contract.

Could someone shed light on the internals of eth_estimateGas
and whether it indeed simulates a dry run of the contract, or if there's a different mechanism at play?