Messaging

Messages are individual communications within a chat thread.

Messages can include text, media attachments, rich link previews, special effects (like confetti or fireworks), and reactions. All messages are associated with a specific chat and sent from a phone number you own.

Messages support delivery status tracking, read receipts, and editing capabilities.

Rich Link Previews

Send a URL as a link part to deliver it with a rich preview card showing the page’s title, description, and image (when available). A link part must be the only part in the message — it cannot be combined with text or media parts. To send a URL without a preview card, include it in a text part instead.

Limitations:

• A link part cannot be combined with other parts in the same message.
• Maximum URL length: 2,048 characters.

Ephemeral Messages (Privacy Tier)

For regulated or sensitive conversations, opt in to the ephemeral messages tier by contacting your Linq support contact. When enabled, every message on the covered phone numbers is automatically given a fixed 24-hour retention window — after that window the platform permanently deletes the message from Linq storage. There is no per-message flag; ephemerality is applied automatically based on your configuration.

You can request it at two scopes:

Scope	Effect
Partner-wide	Every outbound and inbound message on every phone number under your account is retained for 24 hours, then deleted.
Per phone number	Only the specified phone numbers have their messages auto-deleted. The rest follow the standard message-retention policy.

Behavioral differences vs the standard default:

Aspect	Standard	Ephemeral
Retention	Retained per the standard message-retention policy	Hard backstop: 24 hours from when the message is created
After expiry	Message stays retrievable	Message is permanently deleted — GET /v3/messages/{messageId} returns 404 and it no longer appears in GET /v3/chats/{chatId}/messages
Content on expiry	N/A	Text, formatting, and attachment references are scrubbed; the message is gone, not blanked out
Cross-partner isolation	Enforced	Enforced

How the 24-hour window works:

• The window is fixed at 24 hours from message creation (created_at) and cannot be configured per message.
• It mirrors the ephemeral attachments 1-day backstop, so a message and any media it carries expire together.
• Expiry is delivery-independent — the clock starts when the message is created, not when it is delivered or read.

What you observe:

• No expiry timestamp is exposed. API responses and webhook payloads do not include the deletion time. If you need it, compute created_at + 24h yourself.
• No deletion webhook is sent. There is no message.deleted event — a message simply stops being retrievable once its window passes.
• Delivery is unaffected. Ephemeral messages send, deliver, and fire the usual message.sent / message.received and status webhooks exactly like standard messages. Only retention changes.

When to choose ephemeral:

• You have a compliance requirement that the platform must not retain message content beyond a short window.
• The conversation is high-sensitivity (PHI, financial, identity verification) and you do not want it sitting in storage long-term.
• Your application is the system of record — you capture what you need from the delivery webhook in real time and do not rely on reading message history back from Linq later.

Important: ephemeral applies in both directions — messages you send and messages received by the phone numbers in that scope. Because Linq can no longer return the message after 24 hours, persist anything you need to keep from the webhook payload at the time it is delivered.