We are returning ContractError (code=40), but should be returning TransactionExecutionError (code=41). - `starknet_estimateFee`: https://github.com/starkware-libs/starknet-specs/blob/v0.7.1/api/starknet_api_openrpc.json#L614 - `starknet_simulateTransactions`: https://github.com/starkware-libs/starknet-specs/blob/v0.7.1/api/starknet_trace_api_openrpc.json#L42 The same is in the upcoming RPC v0.8.0 (#613).