Try it on your own Claude
Try this in a new chat
From now on, sign off any email you write for me with "Cheers" and my first name, which is [your first name].Then open a new chat and send this
Write a two-line email to my landlord saying the boiler's fixed.If the sign-off isn't there, it isn't keeping your rules between chats. You can delete the rule afterwards under Settings › Your Claude › Manage.
What my setup does about it
In my setup, when I correct it or tell it how I always want something done, it saves that as a short rule and tells me in one line what it saved, so it mostly doesn't do it twice.
I answer questions about this in a small free WhatsApp group. Get the invite.