diff --git a/config/config.exs b/config/config.exs
--- a/config/config.exs
+++ b/config/config.exs
@@ -30,4 +30,9 @@
 #     import_config "#{Mix.env}.exs"
 
 config :kolab_wopi,
+  host_info: [
+               endpoint_desc: "Kolab Systems, Zurich",
+               machine_name: to_string(Node.self()),
+               version: "kolab_wopi_v" <> to_string(Keyword.get(Mix.Project.get!().project(), :version)) #:application.get_key(:kolab_wopi, :description))
+             ],
   chwala_base_url: "http://localhost/chwala/api/"
diff --git a/lib/kolab_wopi/api.ex b/lib/kolab_wopi/api.ex
--- a/lib/kolab_wopi/api.ex
+++ b/lib/kolab_wopi/api.ex
@@ -11,6 +11,7 @@
   require Logger
 
   plug Plug.Logger
+  plug :wopi_headers
   plug :access_token_handler
   plug :match
   plug :dispatch
@@ -34,6 +35,19 @@
 
 
   @doc """
+    Plug that adds the standard WOPI response headers
+
+    @see https://wopirest.readthedocs.io/en/latest/common_headers.html
+  """
+  def wopi_headers(conn, _opts) do
+    host_info = Application.get_env(:kolab_wopi, :host_info)
+    conn
+    |> put_resp_header("X-WOPI-HostEndpoint", Keyword.get(host_info, :endpoint_desc))
+    |> put_resp_header("X-WOPI-MachineName", Keyword.get(host_info, :machine_name))
+    |> put_resp_header("X-WOPI-ServerVersion", Keyword.get(host_info, :version))
+  end
+
+  @doc """
     Plug that fetches query parameters and validates the access_token.
 
     The access_token parameter is required in every WOPI request.
@@ -63,13 +77,20 @@
 
     It supports Chwala status codes.
   """
-  def send_status_resp(conn, code, reason \\ nil)
+  def send_status_resp(conn, code, reason \\ "Unknown error")
 
   def send_status_resp(conn, 403, reason) do
     # Chwala uses only 200, 403, 500, 501, 503
     send_status_resp(conn, 401, reason)
   end
 
+  def send_status_resp(conn, code, reason) when code >= 500 and code < 600 do
+    # TODO: log status reason?
+    conn
+        |> put_resp_header("X-WOPI-ServerError", reason)
+        |> send_resp(code, "")
+  end
+
   def send_status_resp(conn, code, _reason) do
     # TODO: log status reason?
     send_resp(conn, code, "")