node-steam-user VS CSSource-Texture-Installer

https://github.com/DoctorMcKay/node-steam-user is a popular NodeJS library for writing steam bots. This could provide useful, but iirc the method this uses for login will only allow you to have one login session at a time. Steam will automatically kick you out with a "logged in elsewhere" error.

https://github.com/DoctorMcKay/node-steam-user/blob/master/examples/databasedownloader.js - then you can follow the code here to list the game info thanks :D

Depends on what language you're using for JavaScript I think the defacto is anything Doctor McKay makes https://github.com/DoctorMcKay/node-steam-user, https://github.com/DoctorMcKay/node-steam-user etc. If you use python, I'd recommend https://github.com/Gobot1234/steam.py (I'm totally not biased). If you use C# then SteamKit is always a good option. If you use rust then SteamHelper looks interesting although doesn't support too many trading bot features

I don't know any direct resources for learning how the Steam network works, smart people figured it out over many years and lots of reverse engineering. I just know a few programming libraries which you can use to interact with it, the most popular two being Steam-User (JavaScript) and SteamKit2 (.NET).

One way you can do this, is by using the "steam user" node module node-steam-user. to play the games. And use the api call to Steam_Web_API to get the playtime of each of the games the account have.

Use this, it downloads the files directly from Steam and puts them in the correct place for you. Only caveat is that you will need to go into the files to delete the models/humans/ and models/weapons/ folders. (If you don't do this you'll be missing some animations/ everyone will have "crotch guns") The SteamCMD method (Which this uses) is the only free and legal way to get the assets.

This is the best method and 100% legal as it used SteamCMD to download the assets directly from valve. Only caveat when you use this (or any method that isn't using gmods mounting system) is that you will need to delete some files after its finished installing. Delete the models/ weapons folder and the models/ humans folder. If you don't delete these you will have the crotch gun bug and be missing gmod specific animations like swimming or noclip floating.

Use this. (100% legal) https://github.com/ITS-NIGHTOWL/CSSource-Texture-Installer/

Delete the addon for it you currently use. Use this instead.

The better alternative is downloading the CSS assets using this https://github.com/ITS-NIGHTOWL/CSSource-Texture-Installer/ which is 100% legal and is effectively just a wrapper for steamcmd and downloads the assets directly from Steam. That will solve 90% of users issues, getting HL2:E2 on steam will solve the next 9% and the final 1% can be solved by the valve complete pack or removing dodgy addons.