Why does steam ban accounts when working through the API?

Question

API

With crutches and such and such a mother, they made getting inventory, offering an exchange through the steam API, but with any attempt to execute the code, accounts fly into a ban.
The question is - are there any criteria by which they are banned or what does it depend on at all?

Answer 1

trade offers via steam API

Well, everything is correct banyat.
Not to spam.