presto-main/src/main/java/io/prestosql/server/PagesResponseWriter.java/PagesResponseWriter/isWriteable
class PagesResponseWriter:    @Override
    public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType)
    {
        return List.class.isAssignableFrom(type) &&
                TypeToken.of(genericType).resolveType(LIST_GENERIC_TOKEN).getRawType().equals(Page.class) &&
                mediaType.isCompatible(PRESTO_PAGES_TYPE);
    }