What is guardrailed email? Send-time policy enforcement for software & AI

import { SadaSend } from 'sadasend';

// Initialize with a guardrailed agent credential
const sadasend = new SadaSend({ apiKey: process.env.SADASEND_API_KEY! });

export async function sendCustomerUpdate(recipient: string, message: string) {
  try {
    // SadaSend verifies recipient allowlists and spend caps in-flight
    const response = await sadasend.emails.send({
      from: 'billing@yourdomain.com',
      to: recipient,
      subject: 'Account Notification',
      text: message,
      // Built-in pre-send verification guarantees zero debits on dead mailboxes
      verifyBeforeSend: true,
    });

    return { status: 'accepted', id: response.id };
  } catch (error: any) {
    // If the recipient is outside the approved staging allowlist:
    // Throws RecipientNotAllowlistedError (HTTP 422) without debiting send quota
    if (error.code === 'UNAUTHORIZED_RECIPIENT') {
      console.warn('Guardrail intercepted send outside allowlist:', recipient);
    }
    throw error;
  }
}