diff --git a/doc/examples/hello-world/hello-world.sms.ttl b/doc/examples/hello-world/hello-world.sms.ttl
index 17c2caff..90e294b3 100644
--- a/doc/examples/hello-world/hello-world.sms.ttl
+++ b/doc/examples/hello-world/hello-world.sms.ttl
@@ -71,6 +71,21 @@ CONSTRUCT {
 :execute-greeting
   a sm:Function ;
   sm:returnModule :express-greeting_Return ;
+  rdfs:comment "This function constructs a hello world message for a person given their first and last name."
+  spin:constraint [
+    rdf:type spl:Argument ;
+    spl:predicate :firstName ;
+    spl:optional "false"^^xsd:boolean ;
+    rdfs:label "first name" ;
+    rdfs:comment "The first name of the greeted person" ;
+  ] ;
+  spin:constraint [
+    rdf:type spl:Argument ;
+    spl:predicate :lastName ;
+    spl:optional "false"^^xsd:boolean ;
+    rdfs:label "last name" ;
+    rdfs:comment "The last name of the greeted person" ;
+  ] ;
 .
 :express-greeting_Return
   a sml:ReturnRDF ;