diff --git a/lib/ash/doc_index.ex b/lib/ash/doc_index/ash_doc_index.ex
similarity index 73%
rename from lib/ash/doc_index.ex
rename to lib/ash/doc_index/ash_doc_index.ex
index d8841141..cf49b58a 100644
--- a/lib/ash/doc_index.ex
+++ b/lib/ash/doc_index/ash_doc_index.ex
@@ -1,19 +1,13 @@
-defmodule Ash.DocIndex do
-  @moduledoc "A module for configuring how a library is rendered in ash_hq"
-  @type extension :: %{
-          optional(:module) => module,
-          optional(:target) => String.t(),
-          optional(:default_for_target?) => boolean,
-          optional(:name) => String.t(),
-          optional(:type) => String.t()
-        }
-
-  @callback extensions() :: list(extension())
-
-  @behaviour __MODULE__
+defmodule Ash.DocIndex.AshDocIndex do
+  @moduledoc "Doc index for Ash"
+  @behaviour Ash.DocIndex
 
   @impl true
-  @spec extensions() :: list(extension)
+  @spec for_library() :: String.t()
+  def for_library, do: "ash"
+
+  @impl true
+  @spec extensions() :: list(Ash.DocIndex.extension())
   def extensions do
     [
       %{
diff --git a/lib/ash/doc_index/doc_index.ex b/lib/ash/doc_index/doc_index.ex
new file mode 100644
index 00000000..12300fba
--- /dev/null
+++ b/lib/ash/doc_index/doc_index.ex
@@ -0,0 +1,13 @@
+defmodule Ash.DocIndex do
+  @moduledoc "A module for configuring how a library is rendered in ash_hq"
+  @type extension :: %{
+          optional(:module) => module,
+          optional(:target) => String.t(),
+          optional(:default_for_target?) => boolean,
+          optional(:name) => String.t(),
+          optional(:type) => String.t()
+        }
+
+  @callback extensions() :: list(extension())
+  @callback for_library() :: String.t()
+end