Optimizing Message Delivery Rates: A Technical Deep Dive

Achieving high message delivery rates requires understanding the technical nuances of each channel. In this guide, we'll explore advanced optimization strategies used by Zavu to maximize deliverability.

Understanding Delivery Challenges

Message delivery can fail for various reasons:

• Invalid phone numbers - Numbers that don't exist or are incorrectly formatted
• Carrier filtering - Messages blocked by carrier spam filters
• Channel unavailability - WhatsApp not installed, phone off, etc.
• Rate limiting - Exceeding carrier or platform limits
• Content issues - Spam triggers or policy violations

Phone Number Validation

Always validate phone numbers before sending:

typescript
import { Zavu, PhoneValidation } from '@zavu/sdk'

async function validateAndSend(phoneNumber: string) {
  // Comprehensive validation
  const validation = await zavu.phone.validate(phoneNumber)

  if (!validation.valid) {
    console.error('Invalid number:', validation.error)
    return
  }

  // Get detailed information
  console.log({
    formatted: validation.formatted,      // E.164 format
    countryCode: validation.countryCode,  // US, GB, etc.
    carrier: validation.carrier,          // Verizon, AT&T, etc.
    lineType: validation.lineType,        // mobile, landline, voip
    canReceiveSms: validation.canReceiveSms,
    canReceiveWhatsapp: validation.canReceiveWhatsapp
  })

  // Only send to valid mobile numbers
  if (validation.lineType === 'mobile') {
    await zavu.messages.send({
      to: validation.formatted,
      content: 'Your verification code is 123456'
    })
  }
}

Intelligent Channel Selection

Zavu's ML-powered routing selects the optimal channel:

typescript
// Let Zavu's AI choose the best channel
const result = await zavu.messages.send({
  to: '+1234567890',
  content: 'Your package is out for delivery!',
  routing: {
    strategy: 'ml_optimized',
    // Factors considered:
    // - Historical delivery rates per channel
    // - User's channel preferences
    // - Time of day optimization
    // - Cost efficiency
    factors: {
      prioritize: 'delivery_rate', // or 'cost', 'speed'
      maxCost: 0.01,
      deadline: new Date(Date.now() + 3600000) // 1 hour
    }
  }
})

console.log('Selected channel:', result.channel)
console.log('Confidence score:', result.confidence)

Implementing Fallback Chains

Configure automatic fallbacks for failed deliveries:

typescript
const message = await zavu.messages.send({
  to: '+1234567890',
  content: 'Important: Your appointment is tomorrow at 2 PM',
  fallback: {
    enabled: true,
    chain: [
      { channel: 'whatsapp', timeout: 30000 },  // Try WhatsApp first, wait 30s
      { channel: 'sms', timeout: 60000 },       // Fall back to SMS
      { channel: 'email', timeout: 0 }          // Finally try email
    ],
    // Transform content for each channel
    transforms: {
      email: {
        subject: 'Appointment Reminder',
        template: 'appointment_reminder_email'
      }
    }
  }
})

// Track the delivery path
console.log('Delivery attempts:', message.attempts)
// [
//   { channel: 'whatsapp', status: 'failed', reason: 'not_registered' },
//   { channel: 'sms', status: 'delivered', deliveredAt: '2025-01-05T10:30:00Z' }
// ]

Content Optimization

Avoid spam filters with these techniques:

typescript
// Use Zavu's content analyzer
const analysis = await zavu.content.analyze({
  text: 'URGENT!!! Click here to claim your FREE prize NOW!!!',
  channel: 'sms'
})

console.log('Spam score:', analysis.spamScore)        // 0.95 (high risk)
console.log('Issues:', analysis.issues)
// [
//   { type: 'all_caps', severity: 'high' },
//   { type: 'excessive_punctuation', severity: 'medium' },
//   { type: 'spam_keywords', words: ['FREE', 'URGENT', 'Click here'] }
// ]

// Get AI-powered suggestions
console.log('Suggested rewrite:', analysis.suggestion)
// "Your prize is ready to claim. Tap to view details."

Monitoring and Analytics

Track delivery metrics in real-time:

typescript
// Get delivery statistics
const stats = await zavu.analytics.getDeliveryStats({
  startDate: '2025-01-01',
  endDate: '2025-01-31',
  groupBy: 'channel'
})

// Example response
{
  sms: {
    sent: 50000,
    delivered: 48500,
    failed: 1500,
    deliveryRate: 0.97,
    avgDeliveryTime: 2.3 // seconds
  },
  whatsapp: {
    sent: 30000,
    delivered: 29700,
    failed: 300,
    deliveryRate: 0.99,
    avgDeliveryTime: 0.8
  }
}

Performance Benchmarks

Here's what you can expect with optimized delivery:

Metric	Before Optimization	After Optimization

SMS Delivery Rate	92%	97.5%
WhatsApp Delivery	95%	99.2%
Avg Delivery Time	5.2s	1.8s
Cost per Message	$0.012	$0.008

Conclusion

Optimizing message delivery is an ongoing process. Use Zavu's built-in analytics to continuously monitor and improve your delivery rates.

Need help optimizing your message delivery? Contact us or join our Discord community for support and updates.