From Settings > Instructions, you define the editorial context your AI assistant should follow for every action.
Global instructions apply to all your connected sites: editorial tone, target audience, general writing conventions.
Per-site instructions add to or override the global instructions for a specific site: specific HTML formatting, a standard article structure, priority keywords, SEO conventions specific to that site.
Global instructions and per-site instructions are saved separately, each with its own "Save" button.
You don't have to go through this screen to update them: your AI assistant can also edit them directly if you ask it to in the conversation, for example to remember a new style preference.