Updated primer

Opened in favour of #423

Author: Relequestual

index.md

@@ -5,7 +5,7 @@ permalink: /
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-**JSON Schema** is a vocabulary that allows you to **annotate** and **validate** JSON documents.
+**JSON Schema** is a declarative ___domain specific language that allows you to **annotate** and **validate** JSON documents. JSON Schema enables the confident and reliable use of the JSON data format.
 
 
 ## Benefits