[DoritoDog]

Mostly asking for TF2 specifically, but comments on any game are welcome.

1. How does Valve detect bots?
2. What would a nearly undetectable bot have to be like?

[Bacardi]

...this forum is not own by Valve or have straight connection to the Valve corporation.

This forum not focus and specialized with Valve Anti Cheat system.

SourceMod is a mod on server, to get more extra features in game and make some admin tasks easy and simple. (SM mod is like a "hack" to server itself, not players) .

If you want script own SM plugins, you can detect human players from server bots with IsFakeClient(client)

About "undetectable bot", why you ask things like this?
I'm guessing what you are asking is not meant for good.