Retell AI Security Basics

Overview

Security best practices for Retell AI API keys, tokens, and access control.

Prerequisites

• Retell AI SDK installed
• Understanding of environment variables
• Access to Retell AI dashboard

Instructions

Step 1: Configure Environment Variables

# .env (NEVER commit to git)
RETELLAI_API_KEY=sk_live_***
RETELLAI_SECRET=***

# .gitignore
.env
.env.local
.env.*.local

Step 2: Implement Secret Rotation

set -euo pipefail
# 1. Generate new key in Retell AI dashboard
# 2. Update environment variable
export RETELLAI_API_KEY="new_key_here"

# 3. Verify new key works
curl -H "Authorization: Bearer ${RETELLAI_API_KEY}" \
  https://api.retellai.com/health

# 4. Revoke old key in dashboard

Step 3: Apply Least Privilege

Environment	Recommended Scopes
Development	read:*
Staging	read:*, write:limited
Production	Only required scopes

Output

• Secure API key storage
• Environment-specific access controls
• Audit logging enabled

Error Handling

Security Issue	Detection	Mitigation
Exposed API key	Git scanning	Rotate immediately
Excessive scopes	Audit logs	Reduce permissions
Missing rotation	Key age check	Schedule rotation

Examples

Service Account Pattern

const clients = {
  reader: new RetellAIClient({
    apiKey: process.env.RETELLAI_READ_KEY,
  }),
  writer: new RetellAIClient({
    apiKey: process.env.RETELLAI_WRITE_KEY,
  }),
};

Webhook Signature Verification

import crypto from 'crypto';

function verifyWebhookSignature(
  payload: string, signature: string, secret: string
): boolean {
  const expected = crypto.createHmac('sha256', secret).update(payload).digest('hex');
  return crypto.timingSafeEqual(Buffer.from(signature), Buffer.from(expected));
}

Security Checklist

• API keys in environment variables
• .env files in .gitignore
• Different keys for dev/staging/prod
• Minimal scopes per environment
• Webhook signatures validated
• Audit logging enabled

Audit Logging

interface AuditEntry {
  timestamp: Date;
  action: string;
  userId: string;
  resource: string;
  result: 'success' | 'failure';
  metadata?: Record<string, any>;
}

async function auditLog(entry: Omit<AuditEntry, 'timestamp'>): Promise<void> {
  const log: AuditEntry = { ...entry, timestamp: new Date() };

  // Log to Retell AI analytics
  await retellaiClient.track('audit', log);

  // Also log locally for compliance
  console.log('[AUDIT]', JSON.stringify(log));
}

// Usage
await auditLog({
  action: 'retellai.api.call',
  userId: currentUser.id,
  resource: '/v1/resource',
  result: 'success',
});

Resources

• Retell AI Security Guide
• Retell AI API Scopes

Next Steps

For production deployment, see retellai-prod-checklist.