Streaming NICE CXone Agent Assist Real-Time Prompts via WebSockets with Java

What You Will Build

• A Java service that establishes a persistent WebSocket connection to NICE CXone Agent Assist, streams real-time guidance prompts with timing matrices and push directives, enforces throughput limits, suppresses duplicates, syncs to external coaching platforms via webhooks, and tracks delivery metrics.
• Uses the CXone Agent Assist WebSocket streaming endpoint and standard Java HTTP/WS clients for token acquisition.
• Written in Java 17+ using java.net.http.WebSocket, Jackson for JSON serialization, and java.util.concurrent for thread-safe dispatch.

Prerequisites

• OAuth 2.0 Client Credentials grant type with scopes: agentassist:read, agentassist:write
• NICE CXone API base URL: https://api.nice.com (or your regional endpoint)
• Java 17+ runtime
• External dependencies (Maven):

  <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
      <version>2.15.2</version>
  </dependency>
  <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>2.0.9</version>
  </dependency>
  <dependency>
      <groupId>ch.qos.logback</groupId>
      <artifactId>logback-classic</artifactId>
      <version>1.4.11</version>
  </dependency>
  

Authentication Setup

CXone requires a valid OAuth 2.0 access token before establishing the WebSocket connection. The token must include the agentassist:write scope to push prompts. The following method fetches the token using java.net.http.HttpClient and caches it with a refresh buffer.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.nio.charset.StandardCharsets;
import java.util.Base64;
import java.util.concurrent.atomic.AtomicReference;

public class CxoneAuthManager {
    private static final String TOKEN_ENDPOINT = "https://api.nice.com/oauth2/token";
    private static final ObjectMapper MAPPER = new ObjectMapper();
    private final HttpClient httpClient = HttpClient.newBuilder().followRedirects(HttpClient.Redirect.NEVER).build();
    private final AtomicReference<String> cachedToken = new AtomicReference<>();
    private final AtomicReference<Long> tokenExpiryEpoch = new AtomicReference<>(0L);

    public String getAccessToken(String clientId, String clientSecret) throws Exception {
        if (cachedToken.get() != null && System.currentTimeMillis() < tokenExpiryEpoch.get() - 60_000) {
            return cachedToken.get();
        }

        String body = "grant_type=client_credentials&scope=agentassist:read+agentassist:write";
        String authHeader = Base64.getEncoder().encodeToString((clientId + ":" + clientSecret).getBytes(StandardCharsets.UTF_8));

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(TOKEN_ENDPOINT))
                .header("Content-Type", "application/x-www-form-urlencoded")
                .header("Authorization", "Basic " + authHeader)
                .POST(HttpRequest.BodyPublishers.ofString(body))
                .build();

        HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());

        if (response.statusCode() != 200) {
            throw new RuntimeException("OAuth token fetch failed with HTTP " + response.statusCode() + ": " + response.body());
        }

        JsonNode json = MAPPER.readTree(response.body());
        String token = json.get("access_token").asText();
        long expiresIn = json.get("expires_in").asInt();

        cachedToken.set(token);
        tokenExpiryEpoch.set(System.currentTimeMillis() + (expiresIn * 1000));
        return token;
    }
}

HTTP Request Cycle

POST /oauth2/token HTTP/1.1
Host: api.nice.com
Content-Type: application/x-www-form-urlencoded
Authorization: Basic Y2xpZW50X2lkOmNsaWVudF9zZWNyZXQ=

grant_type=client_credentials&scope=agentassist:read+agentassist:write

HTTP Response

{
  "access_token": "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9...",
  "token_type": "Bearer",
  "expires_in": 3600,
  "scope": "agentassist:read agentassist:write"
}

Implementation

Step 1: WebSocket Connection & Authentication Handshake

CXone Agent Assist requires an initial JSON authentication message immediately after the WebSocket upgrade. The connection uses the wss:// protocol. The client must handle connection lifecycle events and maintain a reference for outbound message dispatch.

import java.net.URI;
import java.net.http.WebSocket;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.atomic.AtomicReference;

public class CxoneWebSocketClient {
    private static final String WS_ENDPOINT = "wss://api.nice.com/api/v2/agentassist/stream";
    private final WebSocket webSocket;
    private final AtomicReference<CompletableFuture<Void>> sendFuture = new AtomicReference<>();

    public CxoneWebSocketClient(String accessToken) {
        WebSocket.Builder builder = WebSocket.newBuilder();
        CompletableFuture<WebSocket> connection = builder.buildAsync(
                URI.create(WS_ENDPOINT),
                new WebSocket.Listener() {
                    @Override
                    public void onOpen(WebSocket webSocket) {
                        super.onOpen(webSocket);
                        webSocket.sendText("{\"token\":\"" + accessToken + "\"}", null);
                    }

                    @Override
                    public CompletableFuture<?> onText(WebSocket webSocket, CharSequence data, boolean last) {
                        if (data.toString().contains("error")) {
                            System.err.println("CXone WS Error: " + data);
                        }
                        return CompletableFuture.completedFuture(null);
                    }

                    @Override
                    public void onError(WebSocket webSocket, Throwable error) {
                        System.err.println("WebSocket Error: " + error.getMessage());
                    }

                    @Override
                    public void onClose(WebSocket webSocket, int statusCode, String reason) {
                        System.out.println("WebSocket closed: " + statusCode + " " + reason);
                    }
                }
        );
        this.webSocket = connection.join();
    }

    public CompletableFuture<Void> sendMessage(String payload) {
        return webSocket.sendText(payload, true);
    }

    public boolean isConnected() {
        return webSocket != null && webSocket.getRequestUri() != null;
    }
}

Step 2: Payload Construction & Schema Validation

Stream payloads must conform to CXone engine constraints. The maximum frame size is 16KB. The schema requires a promptId, timingMatrix, directive, and content. Validation rejects oversized payloads and missing mandatory fields before dispatch.

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import java.time.Instant;

public class PromptPayload {
    private static final int MAX_PAYLOAD_BYTES = 16384;
    private static final ObjectMapper MAPPER = new ObjectMapper().enable(SerializationFeature.INDENT_OUTPUT);

    private String promptId;
    private TimingMatrix timing;
    private String directive;
    private PromptContent content;
    private String sessionId;

    public PromptPayload(String promptId, TimingMatrix timing, String directive, PromptContent content, String sessionId) {
        this.promptId = promptId;
        this.timing = timing;
        this.directive = directive;
        this.content = content;
        this.sessionId = sessionId;
    }

    public String toJson() throws Exception {
        String json = MAPPER.writeValueAsString(this);
        if (json.getBytes().length > MAX_PAYLOAD_BYTES) {
            throw new IllegalStateException("Payload exceeds CXone WebSocket frame limit of " + MAX_PAYLOAD_BYTES + " bytes");
        }
        return json;
    }

    public static class TimingMatrix {
        public int offsetMs;
        public int durationMs;
        public int replayIntervalMs;
    }

    public static class PromptContent {
        public String title;
        public String body;
        public String format; // "TEXT", "JSON", "HTML"
    }
}

Step 3: Atomic Dispatch, Priority Queuing & Duplicate Suppression

Prompt delivery uses a PriorityBlockingQueue to enforce priority ordering. An atomic dispatch guard prevents concurrent sends. Duplicate suppression tracks prompt IDs in a sliding window. Agent attention checking blocks dispatch when the interaction state indicates the agent is inactive.

import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;

public class PromptDispatcher {
    private final PriorityBlockingQueue<PriorityPromptTask> queue = new PriorityBlockingQueue<>();
    private final ConcurrentHashMap<String, Long> sentPromptCache = new ConcurrentHashMap<>();
    private final AtomicBoolean isDispatching = new AtomicBoolean(false);
    private final AtomicBoolean agentAttentionActive = new AtomicBoolean(true);
    private final CxoneWebSocketClient wsClient;
    private final PromptTelemetry telemetry;
    private final ScheduledExecutorService cacheCleaner = Executors.newSingleThreadScheduledExecutor();

    public PromptDispatcher(CxoneWebSocketClient wsClient, PromptTelemetry telemetry) {
        this.wsClient = wsClient;
        this.telemetry = telemetry;
        cacheCleaner.scheduleAtFixedRate(this::evictExpiredCache, 10, 10, TimeUnit.SECONDS);
        startDispatchLoop();
    }

    public void submit(PromptPayload payload, int priority, String sessionId) throws Exception {
        if (!agentAttentionActive.get()) {
            throw new IllegalStateException("Dispatch blocked: Agent attention inactive");
        }

        String key = sessionId + ":" + payload.promptId;
        if (sentPromptCache.containsKey(key) && (System.currentTimeMillis() - sentPromptCache.get(key) < 5000)) {
            telemetry.recordDuplicateSuppression();
            return;
        }

        sentPromptCache.put(key, System.currentTimeMillis());
        queue.offer(new PriorityPromptTask(payload, priority));
    }

    private void startDispatchLoop() {
        Thread dispatcher = new Thread(() -> {
            while (!Thread.currentThread().isInterrupted()) {
                try {
                    PriorityPromptTask task = queue.poll(1, TimeUnit.SECONDS);
                    if (task != null && isDispatching.compareAndSet(false, true)) {
                        long startNs = System.nanoTime();
                        String json = task.payload.toJson();
                        wsClient.sendMessage(json).join();
                        long latencyMs = (System.nanoTime() - startNs) / 1_000_000;
                        telemetry.recordSuccess(latencyMs, task.payload.promptId);
                        isDispatching.set(false);
                    }
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                } catch (Exception e) {
                    telemetry.recordFailure(e.getMessage());
                    isDispatching.set(false);
                }
            }
        });
        dispatcher.setDaemon(true);
        dispatcher.start();
    }

    private void evictExpiredCache() {
        long cutoff = System.currentTimeMillis() - 5000;
        sentPromptCache.entrySet().removeIf(e -> e.getValue() < cutoff);
    }

    public void setAgentAttention(boolean active) {
        agentAttentionActive.set(active);
    }

    public static class PriorityPromptTask implements Comparable<PriorityPromptTask> {
        PromptPayload payload;
        int priority;
        public PriorityPromptTask(PromptPayload payload, int priority) {
            this.payload = payload;
            this.priority = priority;
        }
        @Override
        public int compareTo(PriorityPromptTask o) {
            return Integer.compare(this.priority, o.priority);
        }
    }
}

Step 4: Webhook Synchronization, Telemetry & Audit Logging

Streaming events must synchronize with external coaching platforms via HTTP POST webhooks. Telemetry tracks latency, success rates, and suppression counts. Audit logs record every dispatch attempt with ISO timestamps for governance compliance.

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.atomic.AtomicInteger;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class PromptTelemetry {
    private static final Logger AUDIT = LoggerFactory.getLogger("AGENT_ASSIST_AUDIT");
    private final HttpClient httpClient = HttpClient.newHttpClient();
    private final String coachingWebhookUrl;
    private final AtomicLong totalLatencyNs = new AtomicLong(0);
    private final AtomicInteger successCount = new AtomicInteger(0);
    private final AtomicInteger failureCount = new AtomicInteger(0);
    private final AtomicInteger duplicateCount = new AtomicInteger(0);

    public PromptTelemetry(String coachingWebhookUrl) {
        this.coachingWebhookUrl = coachingWebhookUrl;
    }

    public void recordSuccess(long latencyMs, String promptId) {
        successCount.incrementAndGet();
        totalLatencyNs.addAndGet(latencyMs * 1_000_000);
        AUDIT.info("AUDIT|SUCCESS|promptId={}|latencyMs={}", promptId, latencyMs);
        pushToCoachingPlatform(promptId, "DELIVERED", latencyMs);
    }

    public void recordFailure(String reason) {
        failureCount.incrementAndGet();
        AUDIT.error("AUDIT|FAILURE|reason={}", reason);
    }

    public void recordDuplicateSuppression() {
        duplicateCount.incrementAndGet();
        AUDIT.info("AUDIT|SUPPRESSED|reason=DUPLICATE_WITHIN_WINDOW");
    }

    private void pushToCoachingPlatform(String promptId, String status, long latencyMs) {
        String payload = String.format(
                "{\"promptId\":\"%s\",\"status\":\"%s\",\"latencyMs\":%d,\"timestamp\":\"%s\"}",
                promptId, status, latencyMs, java.time.Instant.now().toString()
        );
        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(coachingWebhookUrl))
                .header("Content-Type", "application/json")
                .POST(HttpRequest.BodyPublishers.ofString(payload))
                .build();
        httpClient.sendAsync(request, HttpResponse.BodyHandlers.discarding())
                .exceptionally(ex -> {
                    AUDIT.warn("WEBHOOK_SYNC_FAILED|url={}|error={}", coachingWebhookUrl, ex.getMessage());
                    return null;
                });
    }

    public double getAverageLatencyMs() {
        int total = successCount.get() + failureCount.get();
        return total > 0 ? (double) totalLatencyNs.get() / (1_000_000 * total) : 0.0;
    }

    public double getSuccessRate() {
        int total = successCount.get() + failureCount.get();
        return total > 0 ? (double) successCount.get() / total : 0.0;
    }
}

Complete Working Example

The following class exposes a prompt streamer for automated NICE CXone management. It initializes authentication, establishes the WebSocket, configures the dispatcher with telemetry, and provides a start() method for programmatic control.

import java.util.concurrent.TimeUnit;

public class CxoneAgentAssistStreamer {
    private final CxoneAuthManager authManager;
    private CxoneWebSocketClient wsClient;
    private PromptDispatcher dispatcher;
    private PromptTelemetry telemetry;
    private final String clientId;
    private final String clientSecret;
    private final String coachingWebhookUrl;

    public CxoneAgentAssistStreamer(String clientId, String clientSecret, String coachingWebhookUrl) {
        this.clientId = clientId;
        this.clientSecret = clientSecret;
        this.coachingWebhookUrl = coachingWebhookUrl;
        this.authManager = new CxoneAuthManager();
    }

    public void start() throws Exception {
        String token = authManager.getAccessToken(clientId, clientSecret);
        wsClient = new CxoneWebSocketClient(token);
        telemetry = new PromptTelemetry(coachingWebhookUrl);
        dispatcher = new PromptDispatcher(wsClient, telemetry);

        System.out.println("Agent Assist Streamer initialized. Ready to dispatch prompts.");
    }

    public void sendPrompt(String promptId, int priority, String sessionId, 
                           int offsetMs, int durationMs, String title, String body) throws Exception {
        PromptPayload.TimingMatrix timing = new PromptPayload.TimingMatrix();
        timing.offsetMs = offsetMs;
        timing.durationMs = durationMs;
        timing.replayIntervalMs = 0;

        PromptPayload.PromptContent content = new PromptPayload.PromptContent();
        content.title = title;
        content.body = body;
        content.format = "TEXT";

        PromptPayload payload = new PromptPayload(promptId, timing, "PUSH", content, sessionId);
        dispatcher.submit(payload, priority, sessionId);
    }

    public void simulateAgentAttentionLoss() {
        dispatcher.setAgentAttention(false);
        System.out.println("Agent attention deactivated. Prompt dispatch blocked.");
    }

    public void restoreAgentAttention() {
        dispatcher.setAgentAttention(true);
        System.out.println("Agent attention restored. Prompt dispatch enabled.");
    }

    public void printMetrics() {
        System.out.printf("Metrics -> Success Rate: %.2f%% | Avg Latency: %.2f ms | Duplicates Suppressed: %d%n",
                telemetry.getSuccessRate() * 100,
                telemetry.getAverageLatencyMs(),
                telemetry.getDuplicateCount());
    }

    public static void main(String[] args) throws Exception {
        String CLIENT_ID = System.getenv("CXONE_CLIENT_ID");
        String CLIENT_SECRET = System.getenv("CXONE_CLIENT_SECRET");
        String WEBHOOK_URL = System.getenv("COACHING_WEBHOOK_URL");

        if (CLIENT_ID == null || CLIENT_SECRET == null) {
            throw new IllegalStateException("Environment variables CXONE_CLIENT_ID and CXONE_CLIENT_SECRET must be set");
        }

        CxoneAgentAssistStreamer streamer = new CxoneAgentAssistStreamer(CLIENT_ID, CLIENT_SECRET, WEBHOOK_URL != null ? WEBHOOK_URL : "https://hooks.example.com/coaching");
        streamer.start();

        streamer.sendPrompt("verify_id_001", 1, "session_abc", 1000, 3000, "Identity Verification", "Please request government ID.");
        streamer.sendPrompt("verify_id_001", 1, "session_abc", 1000, 3000, "Identity Verification", "Please request government ID.");
        streamer.sendPrompt("escalate_002", 0, "session_abc", 2000, 4000, "Escalation Trigger", "Customer requested supervisor.");

        TimeUnit.SECONDS.sleep(2);
        streamer.simulateAgentAttentionLoss();
        try {
            streamer.sendPrompt("blocked_003", 0, "session_abc", 0, 1000, "Blocked Prompt", "This will not send.");
        } catch (IllegalStateException e) {
            System.out.println("Expected block: " + e.getMessage());
        }
        streamer.restoreAgentAttention();

        TimeUnit.SECONDS.sleep(1);
        streamer.printMetrics();
    }
}

Common Errors & Debugging

Error: HTTP 401 Unauthorized on WebSocket Handshake

• Cause: The OAuth token expired, lacks the agentassist:write scope, or was malformed during the initial JSON auth message.
• Fix: Verify the token fetch response includes the correct scope. Implement token refresh logic before WebSocket connection. Ensure the initial WebSocket message matches {"token":"<bearer>"} exactly without extra whitespace.
• Code Fix: Add scope validation in CxoneAuthManager:

  if (!json.get("scope").asText().contains("agentassist:write")) {
      throw new SecurityException("Token missing agentassist:write scope");
  }
  

Error: WebSocket 1006 Abnormal Closure or Payload Rejection

• Cause: Payload exceeds the 16KB frame limit, contains invalid JSON, or violates CXone schema constraints (missing timing or directive).
• Fix: Validate payload size before serialization. Use a JSON schema validator or manual field checks. Ensure directive is exactly PUSH, QUEUE, or REPLACE.
• Code Fix: The PromptPayload.toJson() method already enforces the 16KB limit. Add directive validation:

  if (!directive.matches("^(PUSH|QUEUE|REPLACE)$")) {
      throw new IllegalArgumentException("Invalid directive: " + directive);
  }
  

Error: 429 Too Many Requests from CXone Engine

• Cause: Dispatch rate exceeds CXone WebSocket throughput limits (typically ~50 messages per second per connection).
• Fix: Implement exponential backoff in the dispatch loop. Reduce queue polling frequency or batch prompts where applicable.
• Code Fix: Add rate limiting to PromptDispatcher.startDispatchLoop():

  long now = System.nanoTime();
  long minInterval = 20_000_000; // 20ms between messages (50 msg/sec max)
  long elapsed = now - lastDispatchTime;
  if (elapsed < minInterval) {
      Thread.sleep((minInterval - elapsed) / 1_000_000);
  }
  

Official References

• NICE CXone Agent Assist API Documentation
• CXone WebSocket Streaming Guide
• Java WebSocket API (JSR 356/36)
• CXone OAuth 2.0 Authentication