Contacts
Overview
A Contact Object in Sent is an intelligent phone number record that automatically handles validation, formatting, and channel detection. It represents a persistent delivery profile that learns and optimizes how to best reach a specific phone number across different messaging channels.
Every time you provide a phone number to Sent, or create a contact through the Sent Dashboard, a Contact Object is created that enables:
- Smart Routing: Automatically select the best messaging channel (WhatsApp or SMS) for each contact.
- Format Management: Access multiple phone number formats (E164, International, National) for different use cases.
- Channel Detection: Know which messaging channels are available for each contact before sending.
- Delivery Optimization: Learn from delivery patterns to improve routing decisions over time.
The Contact Lifecycle
When you create a contact, it goes through a discovery and optimization process. Understanding this lifecycle helps you build more effective messaging workflows.
One of the most powerful features of Sent contacts is their ability to automatically detect which messaging channels are available for each phone number. When you create a contact, Sent will:
- Validate the phone number and normalize it to international standards.
- Detect WhatsApp availability by checking if the number is registered with WhatsApp Business API.
- Assess SMS capability by validating the carrier and network type.
- Set the optimal default channel based on availability and performance.
- Continuously update channel availability based on delivery results.
💡 This allows you to send messages without worrying about channel compatibility - Sent handles the complexity automatically.
Managing Contacts
Contacts can be managed through the Sent Dashboard or programmatically via the API.
Sent Dashboard
You can manage contacts through the Sent Dashboard. The dashboard provides:
- Search for contacts and filter by contact communication channels
- Create new contacts
- View contact details
- Delete contacts
API Endpoints
The API supports listing and retrieving contacts.
- Contact creation is handled automatically when you send a message to a phone number.
Best Practices
- Use Contact IDs: Always reference contacts by ID rather than raw phone numbers for better performance and routing intelligence.
- Trust the Default Channel: Unless you have specific business requirements, use the contact's default channel for optimal delivery.
- Handle Channel Failures: Implement fallback logic when the default channel is unavailable.
Avoid direct phone number messaging for applications with high contact volume and repeated messaging patterns. While Sent supports direct phone number messaging, bypassing contact creation eliminates routing intelligence and delivery optimization benefits.