diff --git a/README.md b/README.md
index bf805fc..8905f3c 100644
--- a/README.md
+++ b/README.md
@@ -55,13 +55,15 @@ In addition to just being able to repair items, blacksmiths have some random fea
 
 For /blacksmith and /blacksmithconfig, if a new value isn't specified, the current value is displayed instead.
 
-For /blacksmith, using "" or null as the value will clear a custom value, making the NPC use the default value set in
-the config instead. Additionally, every value overridden for an NPC will display a marker (default \[NPC]) when
+For /blacksmith, using -1 or null as the value will clear a custom value, making the NPC use the default value set in
+the config instead. Additionally, every value overridden for an NPC will display a marker (default: \[NPC]) when
 displaying the current value.
 
 Note: basePrice, pricePerDurabilityPoint and enchantmentCost can be set like: `/blacksmithconfig option 4` or
 like `/blacksmithconfig option material/enchantment 4` depending on whether you are setting the default or an override
-for a specific material/enchantment.
+for a specific material/enchantment. For /blacksmithconfig <basePrice/pricePerDurabilityPoint/enchantmentCost> <
+material/enchantment>, using -1 or null as the value will clear the cost for the specified material/enchantment, using
+the default one instead.
 
 ### Presets and filters: