wbcreateclaim

var api = new mw.Api();
api.get({
  action:'query',
  continue:'',
  meta:'tokens',
  format:'json'
}).done(function(token) {
  api.post({
    action: 'wbcreateclaim',
    entity: 'Q4115189',
    property: 'P901',
    snaktype: 'value',
    token: token.query.tokens.csrftoken,
    value: {'entity-type': "item", 'numeric-id':1}
  }).done(function(data) {
    console.log(data);
  });
});