diff --git a/lib/pleroma/emails/user_email.ex b/lib/pleroma/emails/user_email.ex
index ee41ce50a..7e3e9b020 100644
--- a/lib/pleroma/emails/user_email.ex
+++ b/lib/pleroma/emails/user_email.ex
@@ -38,7 +38,12 @@ def password_reset_email(user, password_reset_token) when is_binary(password_res
     |> html_body(html_body)
   end
 
-  def user_invitation_email(user, user_invite_token, to_email, to_name \\ nil) do
+  def user_invitation_email(
+        user,
+        %Pleroma.UserInviteToken{} = user_invite_token,
+        to_email,
+        to_name \\ nil
+      ) do
     registration_url =
       Router.Helpers.redirect_url(
         Endpoint,
diff --git a/test/web/admin_api/admin_api_controller_test.exs b/test/web/admin_api/admin_api_controller_test.exs
index e7ad60aa3..e183da3a1 100644
--- a/test/web/admin_api/admin_api_controller_test.exs
+++ b/test/web/admin_api/admin_api_controller_test.exs
@@ -154,7 +154,7 @@ test "/:right DELETE, can remove from a permission group" do
     end
   end
 
-  describe "POST /api/pleroma/admin/email_invite, with valid parameters" do
+  describe "POST /api/pleroma/admin/email_invite, with valid config" do
     setup do
       registrations_open = Pleroma.Config.get([:instance, :registrations_open])
       invites_enabled = Pleroma.Config.get([:instance, :invites_enabled])
@@ -181,7 +181,75 @@ test "sends invitation and returns 204", %{conn: conn, user: user} do
 
       assert json_response(conn, :no_content)
 
-      Swoosh.TestAssertions.assert_email_sent()
+      token_record = List.last(Pleroma.Repo.all(Pleroma.UserInviteToken))
+      assert token_record
+      refute token_record.used
+
+      Swoosh.TestAssertions.assert_email_sent(
+        Pleroma.UserEmail.user_invitation_email(
+          user,
+          token_record,
+          recipient_email,
+          recipient_name
+        )
+      )
+    end
+
+    test "it returns 403 if requested by a non-admin", %{conn: conn} do
+      non_admin_user = insert(:user)
+
+      conn =
+        conn
+        |> assign(:user, non_admin_user)
+        |> post("/api/pleroma/admin/email_invite?email=foo@bar.com&name=JD")
+
+      assert json_response(conn, :forbidden)
+    end
+  end
+
+  describe "POST /api/pleroma/admin/email_invite, with invalid config" do
+    setup do
+      [user: insert(:user, info: %{is_admin: true})]
+    end
+
+    test "it returns 500 if `invites_enabled` is not enabled", %{conn: conn, user: user} do
+      registrations_open = Pleroma.Config.get([:instance, :registrations_open])
+      invites_enabled = Pleroma.Config.get([:instance, :invites_enabled])
+      Pleroma.Config.put([:instance, :registrations_open], false)
+      Pleroma.Config.put([:instance, :invites_enabled], false)
+
+      on_exit(fn ->
+        Pleroma.Config.put([:instance, :registrations_open], registrations_open)
+        Pleroma.Config.put([:instance, :invites_enabled], invites_enabled)
+        :ok
+      end)
+
+      conn =
+        conn
+        |> assign(:user, user)
+        |> post("/api/pleroma/admin/email_invite?email=foo@bar.com&name=JD")
+
+      assert json_response(conn, :internal_server_error)
+    end
+
+    test "it returns 500 if `registrations_open` is enabled", %{conn: conn, user: user} do
+      registrations_open = Pleroma.Config.get([:instance, :registrations_open])
+      invites_enabled = Pleroma.Config.get([:instance, :invites_enabled])
+      Pleroma.Config.put([:instance, :registrations_open], true)
+      Pleroma.Config.put([:instance, :invites_enabled], true)
+
+      on_exit(fn ->
+        Pleroma.Config.put([:instance, :registrations_open], registrations_open)
+        Pleroma.Config.put([:instance, :invites_enabled], invites_enabled)
+        :ok
+      end)
+
+      conn =
+        conn
+        |> assign(:user, user)
+        |> post("/api/pleroma/admin/email_invite?email=foo@bar.com&name=JD")
+
+      assert json_response(conn, :internal_server_error)
     end
   end