How to make auto

i have some pages without meta tag description.if i put meta tag description at head section that cause duplicate to all pages and that will not unique again.

so i want to make meta tag description to fill pages without meta tag.and leave pages already have meta tag.

so i try this code. ( note: iam newbie dont blame me)

{* Custom META tags *}
{if $smarty.const.ENABLE_META_TAGS}
{if !empty($MetaDescription)}
<meta name=“description” content=“this is test meta tag” />
{/if}
{/if}
and Failed.

can someone help me to make like i want??thanks

So are you using the smarty template system?

yeah…
my head using extension head.tpl

is there any other way??
thanks

Sorry I do not use smarty but would have thought it would be built into the system.