diff --git a/README.md b/README.md
index 07db3b3..55ca355 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,7 @@ of the entire help.
 It includes examples for the following mods:
 
 * `doc_items`: In `doc_items.lua`, for item help. Start here!
+* `doc_identifier`: In `doc_identifier.lua`, for adding lookup tool support for custom entities
 * `doc`: In `doc.lua`, for adding your own categories. For advanced modding
 
 Activate this mod in your world to see some example categories, entries and items added.
diff --git a/depends.txt b/depends.txt
index 93440a2..77d125a 100644
--- a/depends.txt
+++ b/depends.txt
@@ -1,2 +1,3 @@
 doc
 doc_items
+doc_identifier
diff --git a/doc.lua b/doc.lua
index 315d529..972a9dc 100644
--- a/doc.lua
+++ b/doc.lua
@@ -8,7 +8,7 @@ categories.
 ]]
 
 -- Let's start with a very simple text-based category
--- This category only contains simple
+-- This category only contains simple text
 doc.new_category("example1", {
 	-- This is for humans and mandatory
 	name = "Text Example",
@@ -17,14 +17,20 @@ doc.new_category("example1", {
 	-- Reminder: build_formspec determines how the entry data will be presented to the user
 })
 
--- Entry for the aforementioned category. We only add 1 entry
+-- Entry for the aforementioned category. We add 2 entries
 doc.new_entry("example1", "text", {
-	-- This is for humans and mandatory
+	-- This is for the entry title in the user interface, it's mandatory
 	name = "Text example",
 	-- For this category, the entry data is simply the text to be displayed
 	data = "Lorem Minetest dolor sit amet. Bla bla bla bla Minetest bla bla bla bla Mese bla. Bla bla bla bla bla, celeron55 bla bla, bla.",
 })
 
+-- We will use this entry in doc_identifier.lua
+doc.new_entry("example1", "entity", {
+	name = "Entity entry",
+	data = "This is the entry for the entity (added in doc_identifier.lua). The example entity is just a boring cube which floats in the air. Punch it to destroy it.",
+})
+
 -------------------------------------------------------------------------------
 
 -- Category with hidden entry.
diff --git a/doc_identifier.lua b/doc_identifier.lua
new file mode 100644
index 0000000..49c3375
--- /dev/null
+++ b/doc_identifier.lua
@@ -0,0 +1,22 @@
+-- Example for using doc_identifier (Lookup Tool)
+-- NOTE: Use the API to make custom entities identifiable by the lookup tool.
+-- If you do not define any custom entities, using the API is not needed.
+-- This example adds one example entity and adds doc_identifier support for it.
+
+-- To spawn this entity, use the chat command “/spawnentity doc_example:entity”
+minetest.register_entity("doc_example:entity", {
+	physical = true,
+	collide_with_objects = true,
+	visual = "cube",
+	size = { x = 0.2, y = 0.2, z = 0.2 },
+	textures = {"unknown_object.png", "unknown_object.png", "unknown_object.png", "unknown_object.png", "unknown_object.png", "unknown_object.png"},
+	hp_max = 1,
+})
+
+--[[ This is the actual code you need to add doc_identifier support.
+The following code means, whenever you use the lookup tool on the example entity,
+the entry “entity” in category “example1” will be shown. ]]
+doc.sub.identifier.register_object("doc_example:entity", "example1", "entity")
+
+--[[ NOTE: If you don't do this, the lookup tool will show an error message when
+you use it on this entity. ]]
diff --git a/doc_items.lua b/doc_items.lua
index 6892771..3642102 100644
--- a/doc_items.lua
+++ b/doc_items.lua
@@ -59,12 +59,3 @@ doc.sub.items.register_factoid("nodes", "misc", function(category_id, def)
 	return string.format("Example factoid: This item has the drawtype “%s”.", def.drawtype)
 end)
 
--- This factoid adds the drawtype for nodes
-doc.sub.items.register_factoid("nodes", "misc", function(category_id, def)
-	return string.format("Example factoid: This item has the drawtype “%s”.", def.drawtype)
-end)
-
--- This factoid adds the drawtype for nodes
-doc.sub.items.register_factoid("nodes", "misc", function(category_id, def)
-	return string.format("Example factoid: This item has the drawtype “%s”.", def.drawtype)
-end)
diff --git a/init.lua b/init.lua
index e9eee64..370fcf8 100644
--- a/init.lua
+++ b/init.lua
@@ -1,2 +1,3 @@
 dofile(minetest.get_modpath("doc_example").."/doc.lua")
 dofile(minetest.get_modpath("doc_example").."/doc_items.lua")
+dofile(minetest.get_modpath("doc_example").."/doc_identifier.lua")