Added comment clarifying registration API
@@ -108,6 +108,9 @@ var registerWebAPITemplate = template.Must(
// RegisterWebAPI shows a simple message in the browser to point to the CLI
// Listens in /register/:nkey.
+//
+// This is not part of the Tailscale control API, as we could send whatever URL
+// in the RegisterResponse.AuthURL field.
func (h *Headscale) RegisterWebAPI(
writer http.ResponseWriter,
req *http.Request,
