[{reqId}] {exception_url}   PHP Notice: Undefined index: error

from /srv/mediawiki/php-1.37.0-wmf.6/extensions/GrowthExperiments/includes/Rest/Handler/SuggestionsInfoHandler.php(42)
#0 /srv/mediawiki/php-1.37.0-wmf.6/extensions/GrowthExperiments/includes/Rest/Handler/SuggestionsInfoHandler.php(42): MWExceptionHandler::handleError(integer, string, string, integer, array)
#1 /srv/mediawiki/php-1.37.0-wmf.6/includes/libs/objectcache/wancache/WANObjectCache.php(1714): GrowthExperiments\Rest\Handler\SuggestionsInfoHandler->GrowthExperiments\Rest\Handler\{closure}(boolean, integer, array, NULL, array)
#2 /srv/mediawiki/php-1.37.0-wmf.6/includes/libs/objectcache/wancache/WANObjectCache.php(1542): WANObjectCache->fetchOrRegenerate(string, integer, Closure, array, array)
#3 /srv/mediawiki/php-1.37.0-wmf.6/extensions/GrowthExperiments/includes/Rest/Handler/SuggestionsInfoHandler.php(46): WANObjectCache->getWithSetCallback(string, integer, Closure)
#4 /srv/mediawiki/php-1.37.0-wmf.6/includes/Rest/SimpleHandler.php(38): GrowthExperiments\Rest\Handler\SuggestionsInfoHandler->run()
#5 /srv/mediawiki/php-1.37.0-wmf.6/includes/Rest/Router.php(395): MediaWiki\Rest\SimpleHandler->execute()
#6 /srv/mediawiki/php-1.37.0-wmf.6/includes/Rest/Router.php(322): MediaWiki\Rest\Router->executeHandler(GrowthExperiments\Rest\Handler\SuggestionsInfoHandler)
#7 /srv/mediawiki/php-1.37.0-wmf.6/includes/Rest/EntryPoint.php(165): MediaWiki\Rest\Router->execute(MediaWiki\Rest\RequestFromGlobals)
#8 /srv/mediawiki/php-1.37.0-wmf.6/includes/Rest/EntryPoint.php(130): MediaWiki\Rest\EntryPoint->execute()
#9 /srv/mediawiki/php-1.37.0-wmf.6/rest.php(31): MediaWiki\Rest\EntryPoint::main()
#10 /srv/mediawiki/w/rest.php(3): require(string)
#11 {main}