twilio-lookup

Purpose

twilio-lookup enables production-grade phone intelligence workflows using Twilio Lookup: validating phone numbers, normalizing to E.164, retrieving carrier metadata, line type (mobile/landline/VoIP), and caller ID / CNAM (where supported). Engineers use this to:

• Reject invalid or unreachable numbers before sending SMS/WhatsApp/Voice (reduce 21211/30003 failures and cost).
• Route traffic by line type (e.g., avoid SMS to landlines; choose Voice fallback for VoIP-heavy regions).
• Enforce geo/region policy (e.g., block high-risk countries, require US/CA for 10DLC).
• Enrich user profiles with carrier + caller name for fraud scoring and support tooling.
• Build deterministic normalization pipelines (E.164 + country code) across services.

This guide assumes you are integrating Lookup into a larger Twilio production stack (Messaging/Voice/Verify/Studio/SendGrid), with strong error handling, rate limiting, and security controls.

Prerequisites

Accounts & API credentials