agora-welcome is the meta-plugin that onboards new users to the Agora marketplace. Invoke it and it explains what Agora is in plain language, walks through the full install lifecycle (/plugin install <name>@agora), and lists the available plugin categories. It adapts to your input — ask about a single category or a specific plugin and it answers narrowly instead of dumping everything, and when run inside a checked-out Agora repo it reads the real sibling plugin manifests so the list it shows is current rather than memorized.