Druid of the Invisible Hand
For D&D, I want to see an item called "Salt of Protection". Compare Holy Water as an easily purchased magical item.
The player pours the salt in a continuous line, and no divination nor planar travel can enter its wall or circle.
It also addresses the unrelated problem that D&D worlds feel like modern, scientific/deterministic worlds that just have a layer of magic sort of slathered on top. Remove the spellcasting requirement on crafting alchemical items, and let "mundane" items have magical properties without constantly resorting back to "a wizard did it".
How does simple purified salt block divination and conjuration without being enchanted? It's salt. That's what salt does. The protection from evil and magic circle against evil spells are for immediate use and long-term use, respectively, or as an emergency backup for people who can't rely on salt.