Habitica's Community Guidelines page spells out the expectations for Habiticans participating in Community pages such as Guilds, the Tavern, the Habitica Wiki or Trello, etc., or interacting by Private Messaging or otherwise. In some cases, violations of the Community Guidelines can result in consequences, including in extreme cases bans.
All Habiticans should review the Community Guidelines before interacting with one another in either public or private spaces. In addition, if you have concerns about another person's activities or about consequences you have received for infractions, please refer to the Community Guidelines page for more information.
On the Habitica website, you can access the Community Guidelines in the footer on the bottom of every page under the header "Community". In the apps, they are linked in the description of the Tavern.