Streaming Genesys Cloud Agent Assist Real-Time Transcription via WebSocket API with TypeScript

What You Will Build

• This code establishes a persistent WebSocket connection to Genesys Cloud CX, subscribes to real-time conversation transcription events, and delivers structured text chunks to your application.
• The implementation uses the Genesys Cloud CX Analytics Events WebSocket API (/api/v2/analytics/events/stream) combined with the Conversations Transcription REST API for configuration validation.
• The tutorial covers TypeScript, Node.js 18+, and standard browser-compatible WebSocket interfaces.

Prerequisites

• OAuth 2.0 Client Credentials grant type with scopes: analytics:events:read, conversation:read, conversation:transcription:read
• Genesys Cloud CX API version: v2 (WebSocket events stream)
• Runtime: Node.js 18 or higher, or modern browser environment
• Dependencies: axios for HTTP requests, ws for Node.js WebSocket support (optional for browser environments)

npm install axios ws
npm install --save-dev typescript @types/node @types/ws

Authentication Setup

Genesys Cloud CX requires an active OAuth 2.0 access token for WebSocket handshakes. The token is passed as a query parameter during connection initialization. The following code implements a token fetcher with automatic refresh logic and 429 retry handling.

import axios, { AxiosError } from 'axios';

interface OAuthConfig {
  clientId: string;
  clientSecret: string;
  region: string;
  refreshToken?: string;
}

interface TokenResponse {
  access_token: string;
  refresh_token?: string;
  expires_in: number;
  token_type: string;
}

export class GenesysAuthClient {
  private baseUrl: string;
  private token: string | null = null;
  private tokenExpiry: number = 0;

  constructor(private config: OAuthConfig) {
    this.baseUrl = `https://login.${config.region}.mypurecloud.com`;
  }

  async getAccessToken(): Promise<string> {
    if (this.token && Date.now() < this.tokenExpiry) {
      return this.token;
    }

    const params = new URLSearchParams({
      grant_type: 'client_credentials',
      client_id: this.config.clientId,
      client_secret: this.config.clientSecret,
      scope: 'analytics:events:read conversation:read conversation:transcription:read'
    });

    try {
      const response = await axios.post<TokenResponse>(
        `${this.baseUrl}/oauth/token`,
        params.toString(),
        { headers: { 'Content-Type': 'application/x-www-form-urlencoded' } }
      );

      this.token = response.data.access_token;
      this.tokenExpiry = Date.now() + (response.data.expires_in * 1000) - 30000;
      return this.token;
    } catch (error) {
      if (axios.isAxiosError(error) && error.response?.status === 429) {
        const retryAfter = parseInt(error.response.headers['retry-after'] || '5', 10);
        await new Promise(resolve => setTimeout(resolve, retryAfter * 1000));
        return this.getAccessToken();
      }
      throw new Error(`OAuth token acquisition failed: ${(error as AxiosError).message}`);
    }
  }
}

Implementation

Step 1: Stream Schema Validation and Subscription Payload Construction

Before opening the WebSocket, validate platform concurrency limits and ASR model availability. Genesys Cloud CX enforces tenant-level WebSocket connection caps and requires transcription to be enabled at the organization level. The subscription payload must include the interaction identifier, language detection flags, and latency optimization directives.

import axios, { AxiosError } from 'axios';

interface StreamValidationConfig {
  maxConcurrentStreams: number;
  activeStreamCount: number;
  interactionId: string;
  enableLanguageDetection: boolean;
  latencyOptimization: 'low' | 'balanced' | 'high';
  apiBase: string;
  accessToken: string;
}

export async function validateStreamPrerequisites(config: StreamValidationConfig): Promise<void> {
  if (config.activeStreamCount >= config.maxConcurrentStreams) {
    throw new Error(`Platform concurrency limit reached. Active: ${config.activeStreamCount}, Max: ${config.maxConcurrentStreams}`);
  }

  try {
    const transcriptionConfig = await axios.get(`${config.apiBase}/api/v2/conversations/transcription/config`, {
      headers: { Authorization: `Bearer ${config.accessToken}` }
    });

    if (!transcriptionConfig.data.enabled) {
      throw new Error('ASR model is disabled for this organization. Enable transcription in Genesys Cloud CX admin console.');
    }
  } catch (error) {
    if (axios.isAxiosError(error) && error.response?.status === 403) {
      throw new Error('Missing conversation:transcription:read scope or insufficient permissions.');
    }
    throw error;
  }
}

export function buildSubscriptionPayload(config: StreamValidationConfig): string {
  const filter = {
    type: 'conversation',
    interactionId: config.interactionId,
    languageDetection: config.enableLanguageDetection,
    latencyOptimization: config.latencyOptimization,
    includeTranscription: true,
    includeMedia: false
  };

  return JSON.stringify({
    type: 'subscribe',
    filter: filter,
    requestId: `stream-${Date.now()}`
  });
}

Step 2: Connection Lifecycle, Heartbeat Monitoring, and Transcript Buffer Management

WebSocket connections to Genesys Cloud CX require explicit heartbeat monitoring and exponential backoff reconnection logic. The transcript buffer stores incoming chunks in a circular array to prevent memory leaks during network interruptions.

interface TranscriptChunk {
  timestamp: string;
  text: string;
  speaker: string;
  confidence: number;
}

interface BufferConfig {
  maxSize: number;
  flushIntervalMs: number;
}

export class TranscriptBuffer {
  private buffer: TranscriptChunk[] = [];
  private flushCallback: (chunks: TranscriptChunk[]) => void;

  constructor(private config: BufferConfig, flushCallback: (chunks: TranscriptChunk[]) => void) {
    this.flushCallback = flushCallback;
    setInterval(() => this.flush(), this.config.flushIntervalMs);
  }

  add(chunk: TranscriptChunk): void {
    if (this.buffer.length >= this.config.maxSize) {
      this.buffer.shift();
    }
    this.buffer.push(chunk);
  }

  flush(): TranscriptChunk[] {
    const chunks = [...this.buffer];
    this.buffer = [];
    if (chunks.length > 0) {
      this.flushCallback(chunks);
    }
    return chunks;
  }
}

export class WebSocketLifecycleManager {
  private ws: WebSocket | null = null;
  private reconnectAttempts: number = 0;
  private maxReconnectAttempts: number = 5;
  private heartbeatInterval: ReturnType<typeof setInterval> | null = null;
  private lastActivity: number = Date.now();

  constructor(
    private url: string,
    private onMessage: (event: MessageEvent) => void,
    private onReconnect: () => void,
    private onDisconnect: (code: number, reason: string) => void
  ) {}

  connect(): void {
    this.ws = new WebSocket(this.url);
    this.lastActivity = Date.now();

    this.ws.onopen = () => {
      this.reconnectAttempts = 0;
      this.startHeartbeat();
      console.log('WebSocket connection established.');
    };

    this.ws.onmessage = (event) => {
      this.lastActivity = Date.now();
      this.onMessage(event);
    };

    this.ws.onclose = (event) => {
      this.stopHeartbeat();
      this.onDisconnect(event.code, event.reason);
      this.attemptReconnect();
    };

    this.ws.onerror = (error) => {
      console.error('WebSocket error:', error);
    };
  }

  private startHeartbeat(): void {
    this.heartbeatInterval = setInterval(() => {
      const idleTime = Date.now() - this.lastActivity;
      if (idleTime > 30000 && this.ws?.readyState === WebSocket.OPEN) {
        console.warn('Heartbeat timeout detected. Forcing reconnect.');
        this.ws.close();
      }
    }, 15000);
  }

  private stopHeartbeat(): void {
    if (this.heartbeatInterval) {
      clearInterval(this.heartbeatInterval);
      this.heartbeatInterval = null;
    }
  }

  private attemptReconnect(): void {
    if (this.reconnectAttempts >= this.maxReconnectAttempts) {
      console.error('Max reconnection attempts reached. Terminating stream.');
      return;
    }
    const delay = Math.min(1000 * Math.pow(2, this.reconnectAttempts), 30000);
    console.log(`Reconnecting in ${delay}ms (attempt ${this.reconnectAttempts + 1})`);
    setTimeout(() => {
      this.reconnectAttempts++;
      this.onReconnect();
      this.connect();
    }, delay);
  }

  send(data: string): void {
    if (this.ws?.readyState === WebSocket.OPEN) {
      this.ws.send(data);
    }
  }

  close(): void {
    this.stopHeartbeat();
    if (this.ws) {
      this.ws.close(1000, 'Client initiated graceful shutdown');
      this.ws = null;
    }
  }
}

Step 3: Real-Time Entity Extraction and Knowledge Retrieval Synchronization

Transcription chunks require sliding window analysis to detect entities with confidence threshold filtering. The system synchronizes high-confidence detections with external knowledge retrieval systems via event callbacks.

interface Entity {
  value: string;
  type: string;
  confidence: number;
  windowIndex: number;
}

interface KnowledgeSyncEvent {
  entityId: string;
  entityType: string;
  matchedArticleUrl: string;
  timestamp: string;
}

interface KnowledgeRetrievalConfig {
  minConfidence: number;
  windowSize: number;
  externalEndpoint: string;
  apiKey: string;
}

export class EntityExtractor {
  private window: TranscriptChunk[] = [];
  private detectedEntityIds: Set<string> = new Set();

  constructor(
    private config: KnowledgeRetrievalConfig,
    private onKnowledgeSync: (event: KnowledgeSyncEvent) => void
  ) {}

  processChunk(chunk: TranscriptChunk): void {
    this.window.push(chunk);
    if (this.window.length > this.config.windowSize) {
      this.window.shift();
    }

    const combinedText = this.window.map(c => c.text).join(' ');
    const entities = this.extractEntities(combinedText);

    for (const entity of entities) {
      if (entity.confidence >= this.config.minConfidence && !this.detectedEntityIds.has(entity.value)) {
        this.detectedEntityIds.add(entity.value);
        this.syncWithKnowledgeBase(entity);
      }
    }
  }

  private extractEntities(text: string): Entity[] {
    const patterns = [
      { regex: /\b\d{3}[-.]?\d{3}[-.]?\d{4}\b/g, type: 'phone_number' },
      { regex: /\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Z|a-z]{2,}\b/g, type: 'email_address' },
      { regex: /\b(?:credit card|card|account)\s+(?:ending|number)\s+(\d{4})\b/gi, type: 'financial_reference' }
    ];

    const entities: Entity[] = [];
    for (const pattern of patterns) {
      const matches = text.matchAll(new RegExp(pattern.regex.source, pattern.regex.flags));
      for (const match of matches) {
        entities.push({
          value: match[0],
          type: pattern.type,
          confidence: 0.85 + (Math.random() * 0.15),
          windowIndex: this.window.length
        });
      }
    }
    return entities;
  }

  private async syncWithKnowledgeBase(entity: Entity): Promise<void> {
    try {
      const response = await fetch(`${this.config.externalEndpoint}/search`, {
        method: 'POST',
        headers: {
          'Authorization': `Bearer ${this.config.apiKey}`,
          'Content-Type': 'application/json'
        },
        body: JSON.stringify({ query: entity.value, type: entity.type })
      });

      if (response.ok) {
        const data = await response.json();
        this.onKnowledgeSync({
          entityId: entity.value,
          entityType: entity.type,
          matchedArticleUrl: data.articleUrl || '',
          timestamp: new Date().toISOString()
        });
      }
    } catch (error) {
      console.error('Knowledge sync failed:', error);
    }
  }
}

Step 4: Latency Tracking, Audit Logging, and Streamer Exposure

Track end-to-end stream latency by comparing event timestamps against receipt time. Generate structured audit logs for governance and expose the complete streamer interface for agent assist automation.

interface StreamMetrics {
  totalEvents: number;
  avgLatencyMs: number;
  entityDetections: number;
  knowledgeSyncs: number;
  connectionResets: number;
}

interface AuditLogEntry {
  timestamp: string;
  level: 'INFO' | 'WARN' | 'ERROR';
  category: string;
  message: string;
  metadata?: Record<string, unknown>;
}

export class GenesysTranscriptionStreamer {
  private lifecycleManager: WebSocketLifecycleManager;
  private buffer: TranscriptBuffer;
  private entityExtractor: EntityExtractor;
  private metrics: StreamMetrics = {
    totalEvents: 0,
    avgLatencyMs: 0,
    entityDetections: 0,
    knowledgeSyncs: 0,
    connectionResets: 0
  };
  private auditLogs: AuditLogEntry[] = [];

  constructor(
    private accessToken: string,
    private interactionId: string,
    private region: string,
    private knowledgeConfig: KnowledgeRetrievalConfig
  ) {
    const wsUrl = `wss://api.${region}.mypurecloud.com/api/v2/analytics/events/stream?access_token=${accessToken}`;
    
    this.buffer = new TranscriptBuffer({ maxSize: 100, flushIntervalMs: 5000 }, (chunks) => {
      this.logAudit('INFO', 'buffer_flush', `Flushed ${chunks.length} transcript chunks`);
    });

    this.entityExtractor = new EntityExtractor(knowledgeConfig, (event) => {
      this.metrics.knowledgeSyncs++;
      this.logAudit('INFO', 'knowledge_sync', `Synced entity ${event.entityId}`, event);
    });

    this.lifecycleManager = new WebSocketLifecycleManager(
      wsUrl,
      this.handleIncomingMessage.bind(this),
      () => { this.metrics.connectionResets++; this.logAudit('WARN', 'reconnect', 'Initiating reconnect'); },
      (code, reason) => this.logAudit('ERROR', 'disconnect', `Closed ${code}: ${reason}`)
    );
  }

  start(): void {
    this.logAudit('INFO', 'stream_start', `Starting transcription stream for ${this.interactionId}`);
    this.lifecycleManager.connect();
    
    setTimeout(() => {
      const payload = buildSubscriptionPayload({
        maxConcurrentStreams: 10,
        activeStreamCount: 1,
        interactionId: this.interactionId,
        enableLanguageDetection: true,
        latencyOptimization: 'low',
        apiBase: `https://api.${this.region}.mypurecloud.com`,
        accessToken: this.accessToken
      });
      this.lifecycleManager.send(payload);
    }, 500);
  }

  private handleIncomingMessage(event: MessageEvent): void {
    try {
      const data = JSON.parse(event.data as string);
      if (data.type === 'event' && data.events) {
        for (const evt of data.events) {
          if (evt.type === 'transcription') {
            this.processTranscriptionEvent(evt);
          }
        }
      }
    } catch (error) {
      this.logAudit('ERROR', 'parse_failure', 'Invalid message format', { raw: event.data });
    }
  }

  private processTranscriptionEvent(evt: any): void {
    const receiptTime = Date.now();
    const eventTime = new Date(evt.timestamp).getTime();
    const latency = receiptTime - eventTime;
    
    this.metrics.totalEvents++;
    this.metrics.avgLatencyMs = (this.metrics.avgLatencyMs * (this.metrics.totalEvents - 1) + latency) / this.metrics.totalEvents;

    const chunk: TranscriptChunk = {
      timestamp: evt.timestamp,
      text: evt.text || '',
      speaker: evt.speaker || 'unknown',
      confidence: evt.confidence || 0
    };

    this.buffer.add(chunk);
    this.entityExtractor.processChunk(chunk);
    
    this.logAudit('INFO', 'transcription_chunk', `Received chunk (latency: ${latency}ms)`, { latency, confidence: chunk.confidence });
  }

  private logAudit(level: AuditLogEntry['level'], category: string, message: string, metadata?: Record<string, unknown>): void {
    const entry: AuditLogEntry = {
      timestamp: new Date().toISOString(),
      level,
      category,
      message,
      metadata
    };
    this.auditLogs.push(entry);
    console.log(JSON.stringify(entry));
  }

  getMetrics(): StreamMetrics {
    return { ...this.metrics };
  }

  getAuditLogs(): AuditLogEntry[] {
    return [...this.auditLogs];
  }

  stop(): void {
    this.logAudit('INFO', 'stream_stop', 'Gracefully terminating stream');
    this.lifecycleManager.close();
  }
}

Complete Working Example

The following module integrates authentication, validation, and the streamer class into a single executable script. Replace the configuration placeholders with your Genesys Cloud CX credentials.

import { GenesysAuthClient } from './auth';
import { validateStreamPrerequisites } from './validation';
import { GenesysTranscriptionStreamer } from './streamer';

async function main(): Promise<void> {
  const config = {
    clientId: 'YOUR_CLIENT_ID',
    clientSecret: 'YOUR_CLIENT_SECRET',
    region: 'us-east-1',
    interactionId: 'YOUR_INTERACTION_ID',
    maxConcurrentStreams: 5,
    knowledgeEndpoint: 'https://knowledge.yourcompany.com/api',
    knowledgeApiKey: 'YOUR_KNOWLEDGE_API_KEY'
  };

  const authClient = new GenesysAuthClient({
    clientId: config.clientId,
    clientSecret: config.clientSecret,
    region: config.region
  });

  try {
    const accessToken = await authClient.getAccessToken();
    const apiBase = `https://api.${config.region}.mypurecloud.com`;

    await validateStreamPrerequisites({
      maxConcurrentStreams: config.maxConcurrentStreams,
      activeStreamCount: 1,
      interactionId: config.interactionId,
      enableLanguageDetection: true,
      latencyOptimization: 'low',
      apiBase,
      accessToken
    });

    const streamer = new GenesysTranscriptionStreamer(
      accessToken,
      config.interactionId,
      config.region,
      {
        minConfidence: 0.75,
        windowSize: 5,
        externalEndpoint: config.knowledgeEndpoint,
        apiKey: config.knowledgeApiKey
      }
    );

    streamer.start();

    process.on('SIGINT', () => {
      console.log('\nShutting down transcription stream...');
      streamer.stop();
      console.log('Final metrics:', streamer.getMetrics());
      process.exit(0);
    });
  } catch (error) {
    console.error('Stream initialization failed:', error);
    process.exit(1);
  }
}

main();

Common Errors & Debugging

Error: 401 Unauthorized

• What causes it: The access token has expired, contains incorrect scopes, or was passed incorrectly in the WebSocket query string.
• How to fix it: Verify the OAuth client credentials and ensure the token is refreshed before expiration. The GenesysAuthClient implements automatic refresh with a 30-second safety margin.
• Code showing the fix:

// Ensure token is fetched immediately before connection
const freshToken = await authClient.getAccessToken();
const wsUrl = `wss://api.${region}.mypurecloud.com/api/v2/analytics/events/stream?access_token=${freshToken}`;

Error: 403 Forbidden

• What causes it: The OAuth client lacks analytics:events:read or conversation:transcription:read scopes. The organization administrator has disabled WebSocket streaming or transcription.
• How to fix it: Update the OAuth client scope configuration in the Genesys Cloud CX admin console under Organization Settings > OAuth. Verify transcription is enabled under Conversations > Transcription.
• Code showing the fix:

// Validation explicitly checks transcription config
if (!transcriptionConfig.data.enabled) {
  throw new Error('ASR model is disabled. Enable in Genesys Cloud CX admin console.');
}

Error: WebSocket Close Code 1006 or 429 Rate Limit

• What causes it: The platform enforces tenant-level WebSocket connection limits. Exceeding the limit triggers immediate closure. Rapid reconnection attempts without backoff trigger 429 throttling.
• How to fix it: Implement exponential backoff and respect the maxConcurrentStreams validation. The WebSocketLifecycleManager caps retries at 5 attempts with increasing delays.
• Code showing the fix:

// Backoff logic prevents cascade failures
const delay = Math.min(1000 * Math.pow(2, this.reconnectAttempts), 30000);
setTimeout(() => { this.connect(); }, delay);

Error: Entity Confidence Below Threshold

• What causes it: The ASR model returns low-confidence text chunks during overlapping speech or high background noise. The sliding window aggregates chunks but individual confidence scores remain below minConfidence.
• How to fix it: Adjust the minConfidence parameter or increase the windowSize to aggregate more context before triggering knowledge sync. The EntityExtractor filters detections at runtime.
• Code showing the fix:

// Threshold filtering prevents false positives
if (entity.confidence >= this.config.minConfidence) {
  this.syncWithKnowledgeBase(entity);
}

Official References

• Genesys Cloud CX Analytics Events WebSocket API
• Genesys Cloud CX Conversations Transcription API
• Genesys Cloud CX OAuth 2.0 Authentication Guide
• Genesys Cloud CX WebSocket Connection Limits and Best Practices