passing string as a screen resourceid (for example, "resourceid":"string") results in :

PHP Fatal error: Uncaught exception 'Exception' with message 'Incorrect resource provided for screen item' in /srv/www/htdocs/zabbix/api/classes/class.cscreen.php:500
Stack trace:
#0 /srv/www/htdocs/zabbix/api/classes/class.cscreen.php(791): CScreen::check Items(Array)
#1 /srv/www/htdocs/zabbix/api/classes/class.cscreen.php(651): CScreen::addItems(Array)
#2 [internal function]: CScreen::create(Array)
#3 /srv/www/htdocs/zabbix/api/rpc/class.czbxrpc.php(424): call_user_func(Array, Array)
#4 [internal function]: czbxrpc::screen('create', Array)
#5 /srv/www/htdocs/zabbix/api/rpc/class.czbxrpc.php(92): call_user_func(Array, 'create', Array)
#6 /srv/www/htdocs/zabbix/api/rpc/class.cjsonrpc.php(106): czbxrpc::call('screen.create', Array, 'c6d693f1accf81d...')
#7 /srv/www/htdocs/zabbix/api/rpc/class.cjsonrpc.php(58): CJSONrpc->execute(Array)
#8 /srv/www/htdocs/zabbix/api_jsonrpc.php(54): CJSONrpc->process('{ "jsonrpc":"2....')
#9

thrown in /srv/www/htdocs/zabbix/api/classes/class.cscreen.php on line 500