Which API Should I Use?

Which API Should I Use?

Meet the two ways to send messages on Kudosity. Both run on the same platform and share your account, API keys, senders, reporting, and billing — so you can pick what fits your build today and evolve later.

Quick Recommendation

API Comparison

Choose TransmitMessage (V2) when you need:

  • MMS via API (send & receive) - V2 is the only API with MMS support, including an inbound_mms webhook
  • Simple, programmatic sends with modern webhooks - Webhooks are created/managed by API; JSON responses; streamlined API-key auth
  • WhatsApp (send & receive) - Rich WhatsApp messaging, notifications
  • RCS (send & receive) - RCS notifications, rich messaging
  • Track multiple links in one SMS - Auto-detect & track multiple links in a message
  • Your own message reference alongside our message ID - Add a message_ref for reconciliation/workflows

💡 Recommendation: Start on V2. Keep V1 if you rely on multi-recipient requests or custom tracked links. You can use both under the same account and senders.

Feature Comparison

Account & Authentication
  • Unified account & UI: Same login, senders, reporting, and billing across both APIs
  • Auth: V2 uses API-key auth; V1 uses Basic Auth (key + secret)
Webhooks & Delivery
  • Webhooks: V2 webhooks are managed via API (create/list/update/delete). V1 webhooks are configured in the UI
  • Delivery reports: V2 via webhook; V1 via webhook or email
  • Retries: Both retry failed webhook deliveries; V2 has a more granular schedule
Message Features
  • Message Types: V2 supports SMS, MMS, WhatsApp, RCS; V1 supports SMS only
  • Link Tracking: V2 auto-detects multiple links; V1 supports custom domains
  • Multi-recipient: V1 supports batch sends; V2 requires individual requests
  • Response Format: V2 is JSON-only; V1 supports both JSON and XML

Migration Guidance

New Customers

Build on TransmitMessage (V2) to access:

  • MMS capabilities
  • Multi-link tracking
  • Message references
  • API-managed webhooks
  • Modern messaging channels (WhatsApp, RCS)

Existing V1 Customers

No rush to migrate. Continue on TransmitSMS (V1) and consider migrating when you need:

  • MMS support
  • API-managed webhooks
  • Multiple tracked links per message
  • WhatsApp or RCS messaging