diff --git a/apps/emqx_authz/src/emqx_authz.erl b/apps/emqx_authz/src/emqx_authz.erl
index e8c1daf06..b584c32e3 100644
--- a/apps/emqx_authz/src/emqx_authz.erl
+++ b/apps/emqx_authz/src/emqx_authz.erl
@@ -268,7 +268,7 @@ init_source(#{type := Type} = Source) ->
 
 init_metrics(Source) ->
     TypeName = type(Source),
-    ok = emqx_plugin_libs_metrics:create_metrics(
+    emqx_plugin_libs_metrics:create_metrics(
         authz_metrics,
         TypeName,
         [matched, allow, deny, ignore],
diff --git a/apps/emqx_plugin_libs/src/emqx_plugin_libs_metrics.erl b/apps/emqx_plugin_libs/src/emqx_plugin_libs_metrics.erl
index 069760ab5..aea4d0d5d 100644
--- a/apps/emqx_plugin_libs/src/emqx_plugin_libs_metrics.erl
+++ b/apps/emqx_plugin_libs/src/emqx_plugin_libs_metrics.erl
@@ -72,7 +72,7 @@
     rate := #{atom() => rate()}
 }.
 -type handler_name() :: atom().
--type metric_id() :: binary().
+-type metric_id() :: binary() | atom().
 
 -define(CntrRef(Name), {?MODULE, Name}).
 -define(SAMPCOUNT_5M, (?SECS_5M div ?SAMPLING)).