The new `getrpcinfo` shows a list of the active commands and the duration each command has been running. This sounds like a good place to report a completion percentage for any command doing a blockchain rescan, to solve [this problem](https://bitcoin.stackexchange.com/q/83236/90721).
{"change_type", RPCArg::Type::STR,  "set by -changetype", "The output type to use. Only valid if changeAddress is not specified. Options are \"legacy\", \"p2sh-segwit\", and \"bech32\"."},
                            {"includeWatching", RPCArg::Type::BOOL,  "false", "Also select inputs which are watch only"},
                            {"lockUnspents", RPCArg::Type::BOOL,  "false", "Lock selected unspent outputs"},
                            {"feeRate", RPCArg::Type::AMOUNT,  "not set: makes wallet determine the fee", "Set a specific fee rate in " + CURRENCY_UNIT + "/kB"},
                            {"subtractFeeFromOutputs", RPCArg::Type::ARR,  "empty array", "A json array of integers.\n"
                            "                              The fee will be equally deducted from the amount of each specified output.\n"
                            "                              Those recipients will receive less bitcoins than you enter in their corresponding amount field.\n"
                            "                              If no outputs are specified here, the sender pays the fee.",
                                {
                                    {"vout_index", RPCArg::Type::NUM, RPCArg::Optional::OMITTED, "The zero-based output index, before a change output is added."},
                                },
                            },
                            {"replaceable", RPCArg::Type::BOOL,  "fallback to wallet's default", "Marks this transaction as BIP125 replaceable.\n"
                            "                              Allows this transaction to be replaced by a transaction with higher fees"},
                            {"conf_target", RPCArg::Type::NUM,  "fallback to wallet's default", "Confirmation target (in blocks)"},
                            {"estimate_mode", RPCArg::Type::STR,  "UNSET", "The fee estimate mode, must be one of:\n"
                            "         \"UNSET\"\n"
                            "         \"ECONOMICAL\"\n"
                            "         \"CONSERVATIVE\""},
                        },
                        "options"},
                    {"iswitness", RPCArg::Type::BOOL,  "depends on heuristic tests", "Whether the transaction hex is a serialized witness transaction \n"
                            "                              If iswitness is not present, heuristic tests will be used in decoding"},
                },
                RPCResult{
                            "{\n"
                            "  \"hex\":       \"value\", (string)  The resulting raw transaction (hex-encoded string)\n"
                            "  \"fee\":       n,         (numeric) Fee in " + CURRENCY_UNIT + " the resulting transaction pays\n"
                            "  \"changepos\": n          (numeric) The position of the added change output, or -1\n"
                            "}\n"