diff --git a/lib/decentralised_book_index/metadata.ex b/lib/decentralised_book_index/metadata.ex
index deca3d1..3ab9d24 100644
--- a/lib/decentralised_book_index/metadata.ex
+++ b/lib/decentralised_book_index/metadata.ex
@@ -26,18 +26,32 @@ defmodule DecentralisedBookIndex.Metadata do
           :bids,
           :author_roles,
           :publisher_id,
+          {:optional, :cover_image_url},
           {:optional, :book_editions_registry_id}
         ]
 
       define :add_book_to_related_editions_registry,
         action: :add_book_to_related_editions_registry,
-        args: [:title, :description, :language, :format, :page_count, :published, :bids, :author_roles, :publisher_id, :related_book_id]
+        args: [
+          :title,
+          :description,
+          :language,
+          :format,
+          :page_count,
+          :published,
+          :bids,
+          :author_roles,
+          :publisher_id,
+          :related_book_id,
+          {:optional, :cover_image_url}
+        ]
 
       define :list_books, action: :read
       define :get_book_by_id, args: [:id], action: :by_id
       define :get_book_by_bid, args: [:type, :bid], action: :by_bid
       define :get_book_alternative_editions, args: [:book], action: :get_alternative_editions
       define :get_author_books, args: [:author], action: :get_author_books
+      define :search_book, action: :search, args: [:query]
       define :update_book, action: :update
       define :assign_book_cover_image, args: [:cover_image_url], action: :assign_cover_image
       define :destroy_book, action: :destroy
@@ -90,6 +104,7 @@ defmodule DecentralisedBookIndex.Metadata do
       define :create_author_role, action: :create, args: [:author_id, :order, :role]
       define :list_author_roles, action: :read
       define :get_author_role_by_id, args: [:id], action: :by_id
+      define :get_author_roles_by_book_id, args: [:book_id], action: :by_book_id
       define :update_author_role, action: :update
       define :destroy_author_role, action: :destroy
     end
diff --git a/lib/decentralised_book_index/metadata/book.ex b/lib/decentralised_book_index/metadata/book.ex
index 646b6c9..28a6d97 100644
--- a/lib/decentralised_book_index/metadata/book.ex
+++ b/lib/decentralised_book_index/metadata/book.ex
@@ -17,7 +17,7 @@ defmodule DecentralisedBookIndex.Metadata.Book do
 
     create :create do
       primary? true
-      accept [:title, :description, :format, :language, :page_count, :published, :publisher_id, :book_editions_registry_id]
+      accept [:title, :description, :format, :language, :page_count, :published, :publisher_id, :cover_image_url, :book_editions_registry_id]
       argument :bids, {:array, :map}
       argument :author_roles, {:array, :map}
 
@@ -38,7 +38,7 @@ defmodule DecentralisedBookIndex.Metadata.Book do
     end
 
     create :add_book_to_related_editions_registry do
-      accept [:title, :description, :format, :language, :page_count, :published, :publisher_id]
+      accept [:title, :description, :format, :language, :page_count, :published, :publisher_id, :cover_image_url]
 
       argument :related_book_id, :uuid do
         allow_nil? false
diff --git a/test/decentralised_book_index/metadata/book_test.exs b/test/decentralised_book_index/metadata/book_test.exs
index 7c4e07c..81bbd38 100644
--- a/test/decentralised_book_index/metadata/book_test.exs
+++ b/test/decentralised_book_index/metadata/book_test.exs
@@ -19,7 +19,7 @@ defmodule DecentralisedBookIndex.Metadata.BookTest do
       publisher = generate(publisher())
 
       assert {:ok, registry} = Metadata.create_book_editions_registry()
-      assert {:ok, book} = Metadata.create_book("Book", "An description","English", "Paperback", 256, ~D[2025-03-04], bids, author_roles, publisher.id, registry.id)
+      assert {:ok, book} = Metadata.create_book("Book", "An description","English", "Paperback", 256, ~D[2025-03-04], bids, author_roles, publisher.id, nil, registry.id)
       assert book.book_editions_registry_id == registry.id
     end