using grcp api

[ezioadf2]

Hi
Im devloping an v2ray pannel for with node.js but doc is very bad,there is a func called toTypedMessage, i cant understand why developer used it, when we have a proto file standard with normal data type like string,int or etc why developer used a code from golang where we want set a variable for api, for this method i cant develop pannel with node.js, is there any alternarive?
toTypedMessage File
Api examples where method used