based on llmstxt.org the description should be a blockquote

Author: milmazz

lib/ex_doc/formatter/markdown/templates/llms_txt_template.eex

@@ -1,6 +1,6 @@
 # <%= config.project %> v<%= config.version %> - Table of Contents
 <%= if config.description do %>
-<%= config.description %>
+> <%= config.description %>
 
 <% end %>
 <%= nav_group_template config.extra_section, extras %>