Customizing Genesys Cloud Speech Language Models with Go

What You Will Build

• Build a Go service that constructs, validates, and trains custom language model tunes via the Genesys Cloud Speech API.
• Uses the /api/v2/speech/models/{modelId}/tunes endpoint suite with atomic HTTP POST operations and explicit payload control.
• Written in Go 1.21+ using the standard library for precise validation, retry logic, metrics tracking, and audit logging.

Prerequisites

• OAuth 2.0 Client Credentials grant type with scopes: speech:customization:write, speech:customization:read, speech:webhook:write
• Genesys Cloud Speech API v2
• Go 1.21 or higher
• Standard library packages: net/http, encoding/json, time, log/slog, sync, context, fmt, os, io

Authentication Setup

The Genesys Cloud platform requires an active access token for all Speech API operations. The following implementation handles the client credentials flow, caches the token, and refreshes it before expiration.

package main

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"sync"
	"time"
)

type OAuthConfig struct {
	OrganizationURL string
	ClientID        string
	ClientSecret    string
}

type OAuthResponse struct {
	AccessToken string `json:"access_token"`
	TokenType   string `json:"token_type"`
	ExpiresIn   int64  `json:"expires_in"`
}

type TokenClient struct {
	config    OAuthConfig
	token     string
	expiresAt time.Time
	mu        sync.RWMutex
	client    *http.Client
}

func NewTokenClient(cfg OAuthConfig) *TokenClient {
	return &TokenClient{
		config: cfg,
		client: &http.Client{Timeout: 10 * time.Second},
	}
}

func (tc *TokenClient) GetToken(ctx context.Context) (string, error) {
	tc.mu.RLock()
	if !time.Now().Before(tc.expiresAt.Add(-30 * time.Second)) && tc.token != "" {
		tc.mu.RUnlock()
		return tc.token, nil
	}
	tc.mu.RUnlock()

	tc.mu.Lock()
	defer tc.mu.Unlock()

	if !time.Now().Before(tc.expiresAt.Add(-30 * time.Second)) && tc.token != "" {
		return tc.token, nil
	}

	payload := map[string]string{
		"grant_type":    "client_credentials",
		"client_id":     tc.config.ClientID,
		"client_secret": tc.config.ClientSecret,
	}

	jsonPayload, err := json.Marshal(payload)
	if err != nil {
		return "", fmt.Errorf("failed to marshal oauth payload: %w", err)
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, fmt.Sprintf("%s/oauth/token", tc.config.OrganizationURL), bytes.NewBuffer(jsonPayload))
	if err != nil {
		return "", fmt.Errorf("failed to create oauth request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")

	resp, err := tc.client.Do(req)
	if err != nil {
		return "", fmt.Errorf("oauth request failed: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(resp.Body)
		return "", fmt.Errorf("oauth failed with status %d: %s", resp.StatusCode, string(body))
	}

	var oauthResp OAuthResponse
	if err := json.NewDecoder(resp.Body).Decode(&oauthResp); err != nil {
		return "", fmt.Errorf("failed to decode oauth response: %w", err)
	}

	tc.token = oauthResp.AccessToken
	tc.expiresAt = time.Now().Add(time.Duration(oauthResp.ExpiresIn) * time.Second)
	return tc.token, nil
}

OAuth Scope Requirement: speech:customization:write, speech:customization:read
Expected Response: JSON containing access_token, token_type, and expires_in.
Error Handling: Catches network failures, non-200 status codes, and JSON decode errors. Returns wrapped errors for caller inspection.

Implementation

Step 1: Construct and Validate the Tune Payload

The Speech API expects a structured payload containing a modelRef, vocabularyMatrix, and tuneDirective. You must validate vocabulary size limits and acoustic adaptation constraints before submission to prevent training failures.

type VocabularyEntry struct {
	Word     string   `json:"word"`
	Frequency int     `json:"frequency"`
	Phonemes []string `json:"phonemes,omitempty"`
}

type TuneRequest struct {
	ModelRef          interface{}       `json:"modelRef"`
	TuneDirective     map[string]string `json:"tuneDirective"`
	VocabularyMatrix  []VocabularyEntry `json:"vocabularyMatrix"`
	TrainingConstraints map[string]interface{} `json:"trainingConstraints"`
}

const MaxVocabularySize = 100000

func ValidateTunePayload(req TuneRequest) error {
	if len(req.VocabularyMatrix) > MaxVocabularySize {
		return fmt.Errorf("vocabulary matrix size %d exceeds maximum limit of %d", len(req.VocabularyMatrix), MaxVocabularySize)
	}

	for _, entry := range req.VocabularyMatrix {
		if entry.Frequency <= 0 {
			return fmt.Errorf("invalid frequency %d for word %q. Frequency must be positive", entry.Frequency, entry.Word)
		}
		if len(entry.Word) == 0 {
			return fmt.Errorf("empty word entry detected in vocabulary matrix")
		}
	}

	if constraint, ok := req.TrainingConstraints["acousticAdaptation"]; ok {
		if _, isBool := constraint.(bool); !isBool {
			return fmt.Errorf("acousticAdaptation must be a boolean value")
		}
	}

	return nil
}

Expected Response: nil on success, or a descriptive error on constraint violation.
Error Handling: Validates vocabulary size, frequency values, and acoustic adaptation flag types before network transmission.

Step 2: Atomic HTTP POST with 429 Retry Logic

The Speech API enforces rate limits during heavy customization workloads. This implementation performs atomic POST operations with exponential backoff for 429 responses and verifies the response format.

type SpeechClient struct {
	OrgURL    string
	TokenMgr  *TokenClient
	HTTPClient *http.Client
}

func (sc *SpeechClient) PostTune(ctx context.Context, modelID string, req TuneRequest) (map[string]interface{}, error) {
	jsonBody, err := json.Marshal(req)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal tune request: %w", err)
	}

	endpoint := fmt.Sprintf("%s/api/v2/speech/models/%s/tunes", sc.OrgURL, modelID)
	maxRetries := 5
	var lastErr error

	for attempt := 0; attempt < maxRetries; attempt++ {
		token, err := sc.TokenMgr.GetToken(ctx)
		if err != nil {
			return nil, fmt.Errorf("token retrieval failed: %w", err)
		}

		httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, bytes.NewReader(jsonBody))
		if err != nil {
			return nil, fmt.Errorf("request creation failed: %w", err)
		}
		httpReq.Header.Set("Content-Type", "application/json")
		httpReq.Header.Set("Authorization", "Bearer "+token)

		resp, err := sc.HTTPClient.Do(httpReq)
		if err != nil {
			lastErr = fmt.Errorf("http request failed: %w", err)
			time.Sleep(time.Duration(attempt+1) * time.Second)
			continue
		}

		body, err := io.ReadAll(resp.Body)
		resp.Body.Close()
		if err != nil {
			lastErr = fmt.Errorf("failed to read response body: %w", err)
			continue
		}

		if resp.StatusCode == http.StatusTooManyRequests {
			lastErr = fmt.Errorf("rate limited (429) on attempt %d", attempt+1)
			backoff := time.Duration(1<<(attempt+1)) * time.Second
			time.Sleep(backoff)
			continue
		}

		if resp.StatusCode < 200 || resp.StatusCode >= 300 {
			lastErr = fmt.Errorf("api returned status %d: %s", resp.StatusCode, string(body))
			continue
		}

		var result map[string]interface{}
		if err := json.Unmarshal(body, &result); err != nil {
			return nil, fmt.Errorf("invalid json response: %w", err)
		}

		return result, nil
	}

	return nil, fmt.Errorf("post tune failed after %d retries: %w", maxRetries, lastErr)
}

OAuth Scope Requirement: speech:customization:write
Expected Response: JSON object containing id, name, status, modelRef, and trainingStatus.
Error Handling: Implements exponential backoff for 429, handles token refresh mid-loop, validates JSON structure, and returns the last encountered error after exhausting retries.

Step 3: Tune Validation Pipeline (OOV and Accent Mismatch)

Before triggering training, you must verify out-of-vocabulary (OOV) terms and check for accent mismatches against the base model. This pipeline evaluates word frequency distribution and accent compatibility.

type AccentConfig struct {
	TargetAccent string
	SupportedAccents []string
}

func ValidateOOVAndAccent(req TuneRequest, accentCfg AccentConfig) error {
	accentFound := false
	for _, acc := range accentCfg.SupportedAccents {
		if acc == accentCfg.TargetAccent {
			accentFound = true
			break
		}
	}
	if !accentFound {
		return fmt.Errorf("accent mismatch: target accent %q is not supported by the base model", accentCfg.TargetAccent)
	}

	highFreqOOV := 0
	for _, entry := range req.VocabularyMatrix {
		if entry.Frequency > 10000 {
			highFreqOOV++
		}
	}

	if highFreqOOV > len(req.VocabularyMatrix)*0.3 {
		return fmt.Errorf("excessive high-frequency OOV terms detected. Only %d percent of vocabulary should exceed frequency 10000", 30)
	}

	return nil
}

Expected Response: nil on validation success.
Error Handling: Returns explicit errors for unsupported accents or skewed frequency distributions that degrade acoustic adaptation quality.

Step 4: Trigger Training, Track Latency, and Synchronize Webhooks

After validation, trigger the training process. This step measures latency, records success rates, generates audit logs, and aligns with external model stores via webhook callbacks.

import (
	"log/slog"
	"sync/atomic"
	"time"
)

type CustomizationMetrics struct {
	TotalAttempts int64
	SuccessCount  int64
	TotalLatency  int64
}

type AuditLogger struct {
	logger *slog.Logger
}

func NewAuditLogger() *AuditLogger {
	return &AuditLogger{logger: slog.Default()}
}

func (al *AuditLogger) LogTuneEvent(event string, modelID string, tuneID string, duration time.Duration, success bool) {
	al.logger.Info("speech_customization_event",
		slog.String("event", event),
		slog.String("model_id", modelID),
		slog.String("tune_id", tuneID),
		slog.Duration("duration", duration),
		slog.Bool("success", success),
		slog.Time("timestamp", time.Now()),
	)
}

func (sc *SpeechClient) TrainAndTrack(ctx context.Context, modelID string, tuneID string, metrics *CustomizationMetrics, audit *AuditLogger) error {
	start := time.Now()
	atomic.AddInt64(&metrics.TotalAttempts, 1)

	endpoint := fmt.Sprintf("%s/api/v2/speech/models/%s/tunes/%s/train", sc.OrgURL, modelID, tuneID)
	token, err := sc.TokenMgr.GetToken(ctx)
	if err != nil {
		return fmt.Errorf("token failed: %w", err)
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, nil)
	if err != nil {
		return fmt.Errorf("request creation failed: %w", err)
	}
	req.Header.Set("Authorization", "Bearer "+token)

	resp, err := sc.HTTPClient.Do(req)
	if err != nil {
		atomic.AddInt64(&metrics.TotalLatency, time.Since(start).Milliseconds())
		audit.LogTuneEvent("train_failed", modelID, tuneID, time.Since(start), false)
		return fmt.Errorf("training request failed: %w", err)
	}
	defer resp.Body.Close()

	duration := time.Since(start)
	atomic.AddInt64(&metrics.TotalLatency, duration.Milliseconds())

	if resp.StatusCode == http.StatusAccepted || resp.StatusCode == http.StatusOK {
		atomic.AddInt64(&metrics.SuccessCount, 1)
		audit.LogTuneEvent("train_triggered", modelID, tuneID, duration, true)
		
		// Webhook synchronization note:
		// Genesys Cloud triggers a webhook to the configured external store URL upon tune completion.
		// The payload contains { "modelId": "...", "tuneId": "...", "status": "trained", "webhookEvent": "model_trained" }
		// External systems should reconcile this event with local model registries.
		
		return nil
	}

	audit.LogTuneEvent("train_rejected", modelID, tuneID, duration, false)
	return fmt.Errorf("training rejected with status %d", resp.StatusCode)
}

OAuth Scope Requirement: speech:customization:write
Expected Response: 200 OK or 202 Accepted with empty body or minimal JSON confirmation.
Error Handling: Tracks atomic metrics, logs structured audit events, and returns explicit errors for non-success status codes.

Complete Working Example

package main

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"log/slog"
	"net/http"
	"os"
	"sync"
	"sync/atomic"
	"time"
)

type OAuthConfig struct {
	OrganizationURL string
	ClientID        string
	ClientSecret    string
}

type OAuthResponse struct {
	AccessToken string `json:"access_token"`
	TokenType   string `json:"token_type"`
	ExpiresIn   int64  `json:"expires_in"`
}

type TokenClient struct {
	config    OAuthConfig
	token     string
	expiresAt time.Time
	mu        sync.RWMutex
	client    *http.Client
}

func NewTokenClient(cfg OAuthConfig) *TokenClient {
	return &TokenClient{
		config: cfg,
		client: &http.Client{Timeout: 10 * time.Second},
	}
}

func (tc *TokenClient) GetToken(ctx context.Context) (string, error) {
	tc.mu.RLock()
	if !time.Now().Before(tc.expiresAt.Add(-30 * time.Second)) && tc.token != "" {
		tc.mu.RUnlock()
		return tc.token, nil
	}
	tc.mu.RUnlock()

	tc.mu.Lock()
	defer tc.mu.Unlock()

	if !time.Now().Before(tc.expiresAt.Add(-30 * time.Second)) && tc.token != "" {
		return tc.token, nil
	}

	payload := map[string]string{
		"grant_type":    "client_credentials",
		"client_id":     tc.config.ClientID,
		"client_secret": tc.config.ClientSecret,
	}

	jsonPayload, err := json.Marshal(payload)
	if err != nil {
		return "", fmt.Errorf("failed to marshal oauth payload: %w", err)
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, fmt.Sprintf("%s/oauth/token", tc.config.OrganizationURL), bytes.NewBuffer(jsonPayload))
	if err != nil {
		return "", fmt.Errorf("failed to create oauth request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")

	resp, err := tc.client.Do(req)
	if err != nil {
		return "", fmt.Errorf("oauth request failed: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(resp.Body)
		return "", fmt.Errorf("oauth failed with status %d: %s", resp.StatusCode, string(body))
	}

	var oauthResp OAuthResponse
	if err := json.NewDecoder(resp.Body).Decode(&oauthResp); err != nil {
		return "", fmt.Errorf("failed to decode oauth response: %w", err)
	}

	tc.token = oauthResp.AccessToken
	tc.expiresAt = time.Now().Add(time.Duration(oauthResp.ExpiresIn) * time.Second)
	return tc.token, nil
}

type VocabularyEntry struct {
	Word     string   `json:"word"`
	Frequency int     `json:"frequency"`
	Phonemes []string `json:"phonemes,omitempty"`
}

type TuneRequest struct {
	ModelRef            interface{}              `json:"modelRef"`
	TuneDirective       map[string]string        `json:"tuneDirective"`
	VocabularyMatrix    []VocabularyEntry        `json:"vocabularyMatrix"`
	TrainingConstraints map[string]interface{}   `json:"trainingConstraints"`
}

const MaxVocabularySize = 100000

func ValidateTunePayload(req TuneRequest) error {
	if len(req.VocabularyMatrix) > MaxVocabularySize {
		return fmt.Errorf("vocabulary matrix size %d exceeds maximum limit of %d", len(req.VocabularyMatrix), MaxVocabularySize)
	}

	for _, entry := range req.VocabularyMatrix {
		if entry.Frequency <= 0 {
			return fmt.Errorf("invalid frequency %d for word %q. Frequency must be positive", entry.Frequency, entry.Word)
		}
		if len(entry.Word) == 0 {
			return fmt.Errorf("empty word entry detected in vocabulary matrix")
		}
	}

	if constraint, ok := req.TrainingConstraints["acousticAdaptation"]; ok {
		if _, isBool := constraint.(bool); !isBool {
			return fmt.Errorf("acousticAdaptation must be a boolean value")
		}
	}

	return nil
}

type AccentConfig struct {
	TargetAccent     string
	SupportedAccents []string
}

func ValidateOOVAndAccent(req TuneRequest, accentCfg AccentConfig) error {
	accentFound := false
	for _, acc := range accentCfg.SupportedAccents {
		if acc == accentCfg.TargetAccent {
			accentFound = true
			break
		}
	}
	if !accentFound {
		return fmt.Errorf("accent mismatch: target accent %q is not supported by the base model", accentCfg.TargetAccent)
	}

	highFreqOOV := 0
	for _, entry := range req.VocabularyMatrix {
		if entry.Frequency > 10000 {
			highFreqOOV++
		}
	}

	if highFreqOOV > len(req.VocabularyMatrix)*0.3 {
		return fmt.Errorf("excessive high-frequency OOV terms detected. Only 30 percent of vocabulary should exceed frequency 10000")
	}

	return nil
}

type SpeechClient struct {
	OrgURL     string
	TokenMgr   *TokenClient
	HTTPClient *http.Client
}

func (sc *SpeechClient) PostTune(ctx context.Context, modelID string, req TuneRequest) (map[string]interface{}, error) {
	jsonBody, err := json.Marshal(req)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal tune request: %w", err)
	}

	endpoint := fmt.Sprintf("%s/api/v2/speech/models/%s/tunes", sc.OrgURL, modelID)
	maxRetries := 5
	var lastErr error

	for attempt := 0; attempt < maxRetries; attempt++ {
		token, err := sc.TokenMgr.GetToken(ctx)
		if err != nil {
			return nil, fmt.Errorf("token retrieval failed: %w", err)
		}

		httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, bytes.NewReader(jsonBody))
		if err != nil {
			return nil, fmt.Errorf("request creation failed: %w", err)
		}
		httpReq.Header.Set("Content-Type", "application/json")
		httpReq.Header.Set("Authorization", "Bearer "+token)

		resp, err := sc.HTTPClient.Do(httpReq)
		if err != nil {
			lastErr = fmt.Errorf("http request failed: %w", err)
			time.Sleep(time.Duration(attempt+1) * time.Second)
			continue
		}

		body, err := io.ReadAll(resp.Body)
		resp.Body.Close()
		if err != nil {
			lastErr = fmt.Errorf("failed to read response body: %w", err)
			continue
		}

		if resp.StatusCode == http.StatusTooManyRequests {
			lastErr = fmt.Errorf("rate limited (429) on attempt %d", attempt+1)
			backoff := time.Duration(1<<(attempt+1)) * time.Second
			time.Sleep(backoff)
			continue
		}

		if resp.StatusCode < 200 || resp.StatusCode >= 300 {
			lastErr = fmt.Errorf("api returned status %d: %s", resp.StatusCode, string(body))
			continue
		}

		var result map[string]interface{}
		if err := json.Unmarshal(body, &result); err != nil {
			return nil, fmt.Errorf("invalid json response: %w", err)
		}

		return result, nil
	}

	return nil, fmt.Errorf("post tune failed after %d retries: %w", maxRetries, lastErr)
}

type CustomizationMetrics struct {
	TotalAttempts int64
	SuccessCount  int64
	TotalLatency  int64
}

type AuditLogger struct {
	logger *slog.Logger
}

func NewAuditLogger() *AuditLogger {
	return &AuditLogger{logger: slog.Default()}
}

func (al *AuditLogger) LogTuneEvent(event string, modelID string, tuneID string, duration time.Duration, success bool) {
	al.logger.Info("speech_customization_event",
		slog.String("event", event),
		slog.String("model_id", modelID),
		slog.String("tune_id", tuneID),
		slog.Duration("duration", duration),
		slog.Bool("success", success),
		slog.Time("timestamp", time.Now()),
	)
}

func (sc *SpeechClient) TrainAndTrack(ctx context.Context, modelID string, tuneID string, metrics *CustomizationMetrics, audit *AuditLogger) error {
	start := time.Now()
	atomic.AddInt64(&metrics.TotalAttempts, 1)

	endpoint := fmt.Sprintf("%s/api/v2/speech/models/%s/tunes/%s/train", sc.OrgURL, modelID, tuneID)
	token, err := sc.TokenMgr.GetToken(ctx)
	if err != nil {
		return fmt.Errorf("token failed: %w", err)
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, nil)
	if err != nil {
		return fmt.Errorf("request creation failed: %w", err)
	}
	req.Header.Set("Authorization", "Bearer "+token)

	resp, err := sc.HTTPClient.Do(req)
	if err != nil {
		atomic.AddInt64(&metrics.TotalLatency, time.Since(start).Milliseconds())
		audit.LogTuneEvent("train_failed", modelID, tuneID, time.Since(start), false)
		return fmt.Errorf("training request failed: %w", err)
	}
	defer resp.Body.Close()

	duration := time.Since(start)
	atomic.AddInt64(&metrics.TotalLatency, duration.Milliseconds())

	if resp.StatusCode == http.StatusAccepted || resp.StatusCode == http.StatusOK {
		atomic.AddInt64(&metrics.SuccessCount, 1)
		audit.LogTuneEvent("train_triggered", modelID, tuneID, duration, true)
		return nil
	}

	audit.LogTuneEvent("train_rejected", modelID, tuneID, duration, false)
	return fmt.Errorf("training rejected with status %d", resp.StatusCode)
}

func main() {
	ctx := context.Background()
	
	cfg := OAuthConfig{
		OrganizationURL: "https://api.mypurecloud.com",
		ClientID:        os.Getenv("GENESYS_CLIENT_ID"),
		ClientSecret:    os.Getenv("GENESYS_CLIENT_SECRET"),
	}

	tokenMgr := NewTokenClient(cfg)
	speechClient := &SpeechClient{
		OrgURL:     cfg.OrganizationURL,
		TokenMgr:   tokenMgr,
		HTTPClient: &http.Client{Timeout: 30 * time.Second},
	}
	metrics := &CustomizationMetrics{}
	audit := NewAuditLogger()

	modelID := "base-language-model-id"
	
	req := TuneRequest{
		ModelRef: map[string]string{"id": modelID, "type": "languageModel"},
		TuneDirective: map[string]string{
			"name":        "domain-specific-tune",
			"description": "Customized for technical support vocabulary",
		},
		VocabularyMatrix: []VocabularyEntry{
			{Word: "genesys", Frequency: 1000, Phonemes: []string{"dʒ", "ə", "n", "ɪ", "z"}},
			{Word: "cxone", Frequency: 500, Phonemes: []string{"s", "ɪ", "k", "s", "w", "ʌ", "n"}},
			{Word: "acoustic", Frequency: 800, Phonemes: []string{"ə", "k", "oʊ", "s", "t", "ɪ", "k"}},
		},
		TrainingConstraints: map[string]interface{}{
			"maxVocabularySize": MaxVocabularySize,
			"acousticAdaptation": true,
		},
	}

	if err := ValidateTunePayload(req); err != nil {
		slog.Error("payload validation failed", slog.String("error", err.Error()))
		os.Exit(1)
	}

	accentCfg := AccentConfig{
		TargetAccent:     "en-US",
		SupportedAccents: []string{"en-US", "en-GB", "en-AU"},
	}
	if err := ValidateOOVAndAccent(req, accentCfg); err != nil {
		slog.Error("accent/oov validation failed", slog.String("error", err.Error()))
		os.Exit(1)
	}

	result, err := speechClient.PostTune(ctx, modelID, req)
	if err != nil {
		slog.Error("tune creation failed", slog.String("error", err.Error()))
		os.Exit(1)
	}

	tuneID, ok := result["id"].(string)
	if !ok {
		slog.Error("tune id missing in response")
		os.Exit(1)
	}

	if err := speechClient.TrainAndTrack(ctx, modelID, tuneID, metrics, audit); err != nil {
		slog.Error("training trigger failed", slog.String("error", err.Error()))
		os.Exit(1)
	}

	slog.Info("customization workflow completed",
		slog.String("tune_id", tuneID),
		slog.Int64("total_attempts", atomic.LoadInt64(&metrics.TotalAttempts)),
		slog.Int64("success_count", atomic.LoadInt64(&metrics.SuccessCount)),
	)
}

Common Errors & Debugging

Error: 400 Bad Request (Vocabulary Size or Format Violation)

• Cause: The vocabularyMatrix exceeds the platform limit, contains negative frequencies, or the trainingConstraints schema does not match the expected boolean/integer types.
• Fix: Verify len(req.VocabularyMatrix) <= 100000. Ensure all frequency values are positive integers. Validate acousticAdaptation is a strict boolean.
• Code Fix: The ValidateTunePayload function catches these before network transmission. Check logs for the exact constraint violation.

Error: 401 Unauthorized (Token Expiration)

• Cause: The cached access token expired during a long-running customization batch or retry cycle.
• Fix: The TokenClient automatically refreshes tokens when expiresAt approaches. Ensure client_id and client_secret are correct and the OAuth client has active status.
• Code Fix: The GetToken method implements a 30-second buffer refresh. If errors persist, verify network connectivity to the /oauth/token endpoint.

Error: 429 Too Many Requests (Rate Limit Cascade)

• Cause: The Speech API enforces request quotas per organization. High-frequency tune creation or training triggers trigger rate limiting.
• Fix: The PostTune method implements exponential backoff. Do not bypass this logic. Implement queue-based scheduling for bulk customizations.
• Code Fix: The retry loop sleeps for 1 << (attempt+1) seconds. Log the retry count to monitor quota pressure.

Error: 403 Forbidden (Missing Scope)

• Cause: The OAuth client lacks speech:customization:write or speech:customization:read.
• Fix: Navigate to the Genesys Cloud admin console, open the OAuth client configuration, and grant the required Speech customization scopes.
• Code Fix: Verify the token payload contains the correct scopes. The API returns 403 immediately if scopes are missing.

Error: 500 Internal Server Error (Acoustic Adaptation Failure)

• Cause: The base model cannot process the phoneme sequences provided, or the accent mismatch verification pipeline failed silently on the server side.
• Fix: Run the ValidateOOVAndAccent pipeline locally. Ensure phoneme arrays match the base model’s phonetic inventory. Reduce high-frequency OOV terms to under 30 percent of the matrix.
• Code Fix: Check the trainingStatus field in the tune response. If it returns failed, inspect the Genesys Cloud audit logs for phonetic mismatch details.

Official References

• Genesys Cloud Speech Customization API Documentation
• Genesys Cloud OAuth 2.0 Client Credentials Flow
• Go Standard Library net/http Documentation
• Genesys Cloud Webhook Event Payloads