private WandType resolveWandType(Index index, IndexFacts.Session indexFacts, Query query) {
            if (index.isNull()) {
                throw new IllegalInputException("Field '" + fieldName + "' was not found in " + indexFacts);
            } else {
                return WandType.create(query.properties().getString(WAND_TYPE, "vespa"));
            }
        }
Class to resolve the inputs used by this searcher.
container-search/src/main/java/com/yahoo/search/querytransform/WandSearcher.java