ORES is a service that provides scoring for revision for example scoring about an edit being vandalism. If you want to see what the API does, you can try scoring an edit like this:
You can read more about ORES in Wikidata in this blog post (English).
You can use ORES review tool by enabling it in Special:Preferences#mw-prefsection-betafeatures
There are some vandalism we miss and some non-vandalism that we flag. We'll be working on the prediction strategy to improve accuracy over the next couple of months. In order to help us you can report mistakes flagged by ORES in this page