--- /dev/null
+# http\Client\Request http\Client\Request::addQuery(mixed $query_data)
+
+Add querystring data.
+See http\Client\Request::setQuery() and http\Message::setRequestUrl().
+
+## Params:
+
+* mixed $query_data
+ Additional querystring data.
+
+## Returns:
+
+* http\Client\Request, self.