How to moderate a Mastodon instance

This article is a draft! A lot of info might still be missing and the page might change at any time.

Defining rules

Technical:

Only admins can define rules in Settings > Administration > Server rules.
It's very simple. You enter a rule in the text field and hit "Add rule".

Contentual:

Most instances probably have a rule about not doing anything that is illegal in the country the server is operated in.
Other than that rules vary a lot.
An incomplete list of things that can make sense to disallow are: spam, trolling, harassment, hate-speech, discrimination, porn, ...

Dealing with reports

Technical:

Go to Settings > Moderation > Reports to see open reports. Here you'll see who is being reported on, the origin of the report (either an account on your instance or just the name of another instance), how many posts were reported, how many media attachments were reported, how many notes by moderators are already written about the report and whether the account is already suspended by the home instance.
Click on a report to see more info and deal with it. [...]

Contentual:

So what should you do with the report?

• If rules of your instance are obviously broken and the account in question either seems to do so intentionally or exclusively (e.g. account created only for spam) or the account was warned before (Question for the mod team: How many strikes does it take?) then you can suspend the account.
  • If the whole instance the reported account is on seems to break your rules, think about a domain block (See below).
• If rules are broken, but it might be because the user didn't know about the rules, you can start with a warning. Delete or hide the post according to the severity of the violation.
• If it's not obvious whether the reported behavior constitutes a rule break, you can discuss it with the other moderators of your instance (Just add a note to the report and wait what the others say). If you are the only moderator you could ask the reported person to clarify what they mean or remove their questionable content themselves. Depending on whether they comply you can go from there.
• If no rules are broken and there is nothing wrong with the reported account just resolve the report.

Preemptive moderation

You don't need to wait for others to report harmful content, but you can actively look for it.
If you're an admin you'll get notified about everybody who signs up on your instance. Check their profile a while after they created it and you'll be able to weed out a lot of spam accounts already.
Follow the hashtags #MastoAdmin and #FediBlock to see warnings by other users about accounts and instances that might be worth blocking.

If you want to moderate an account just click on the 3-dot menu and then "Open moderation interface". You'll have about the same options as with a reported account.
If you're not sure what to do with the account and want to discuss with the other moderators, just report the account yourself and leave a note.