diff --git a/README.md b/README.md
index 38ebf22..5d1e767 100644
--- a/README.md
+++ b/README.md
@@ -26,7 +26,7 @@ throwing.bow_cooldown = 0.2
 
 There are two available functions in the mod API:
 ```lua
-function throwing.register_bow(name, definition, no_toolranks)
+function throwing.register_bow(name, definition)
 --[[
 Name: Bow name. If it doesn't contain ":", the "throwing:" prefix will be added.
 Definition: definition table, containing:
@@ -49,7 +49,7 @@ Definition: definition table, containing:
   * function spawn_arrow_entity(position, arrow, player): defaults to throwing.spawn_arrow_entity
   * sound: sound to be played when the bow is used
   * delay: delay before throwing the arrow
-  * no_toolranks: Disable toolranks support on this item. Defaults to false.
+  * no_toolranks: If true, toolranks support is disabled for this item. Defaults to false.
 ]]
 
 -- Example:
diff --git a/init.lua b/init.lua
index ecbed3a..b966ca2 100644
--- a/init.lua
+++ b/init.lua
@@ -305,7 +305,7 @@ end
 
 ---------- Bows -----------
 function throwing.register_bow(name, def)
-	local enable_toolrank = use_toolranks and not def.no_toolranks and not def.original_description
+	local enable_toolranks = use_toolranks and not def.no_toolranks
 	if not def.allow_shot then
 		def.allow_shot = function(player, itemstack, index)
 			if index >= player:get_inventory():get_size("main") and not def.throw_itself then
@@ -377,7 +377,7 @@ function throwing.register_bow(name, def)
 		return itemstack
 	end
 	if enable_toolranks then
-		def.original_description = def.description
+		def.original_description = def.original_description or def.description
 		def.description = toolranks.create_description(def.description, 0, 1)
 	end
 	minetest.register_tool(name, def)