public Future<Void> startSpan(ProxyContext context) {
        return vertx.executeBlocking(() -> {
            ResourceDescriptor resource = toResource(context.getTraceId());
            resourceService.computeResource(resource, json -> {
                TraceContext traceContext = ProxyUtil.convertToObject(json, TraceContext.class);
                if (traceContext == null) {
                    traceContext = new TraceContext();
                }
                traceContext.addSpan(context);
                return ProxyUtil.convertToString(traceContext);
            });
            return null;
        }, false);
    }
Starts current span.
<p>
    Note. The method is blocking and shouldn't be run in the event loop thread.
</p>
server/src/main/java/com/epam/aidial/core/server/token/TokenStatsTracker.java