protected final boolean shouldSkipFilter(I inMesg, ZuulFilter<I, O> filter) {
        if (filter.filterType() == FilterType.ENDPOINT) {
            // Endpoints may not be skipped
            return false;
        }
        SessionContext zuulCtx = inMesg.getContext();
        if (zuulCtx.shouldStopFilterProcessing() && !filter.overrideStopFilterProcessing()) {
            return true;
        }
        if (zuulCtx.isCancelled()) {
            return true;
        }
        if (!filter.shouldFilter(inMesg)) {
            return true;
        }
        return false;
    }
This is typically set by a filter when wanting to reject a request and also reduce load on the server by
 not processing anymore filterChain
zuul-core/src/main/java/com/netflix/zuul/netty/filter/BaseZuulFilterRunner.java