Verbs that describe user Do's and Don'ts

A lot of websites have code of conduct that describe user do's and don'ts. For example:

"Stack Exchange <verb1> users to post relevant and constructive answers and <verb2> users to post off-topic discussions."

In this context, what should be appropriate for verb1 and verb2? I have come up with the following candidates but none of them seems right:

verb1: enforces, verb2: forbid (These verbs seem too serious)

verb1: recommends, verb2: discourages

Solution 1:

I would go with encourages and discourages. While those don't necessarily present as "musts", as in technically you can fail to receive the encouragement/discouragement, the point still comes across. It's similar to your second suggestion.

Requires and forbids are also useful, but you found forbids to be too serious; perhaps requires and disallows.

"must" and "must not" also achieve similar purposes, though they are adverbs. However, the word order would need to be changed:

"Stack Exchange users must post relevant and constructive answers and must not post off-topic discussions."