Key concept: what is a session window
A session window is the period during which we can freely reply to a user after their last incoming message. When the window closes:
We can only resume messaging if the user sends a new message, or
On channels that allow it, if we send an approved template/message.
How Darwin AI handles it by channel
Session duration: 24 hours from the user’s last message.
Renewal: each new user message resets the 24-hour timer.
Darwin support: fully supported.
Post-session rule: after 24 hours, you can only send using approved templates (HSM).
Instagram Direct Messages
Current status in Darwin: restricted to 24 hours.
Behavior: after 24 hours, the conversation locks on Darwin’s side; it continues only if the user writes again.
Meta window: up to 7 days from the user’s last message (pending implementation in Darwin).
Facebook Messenger
Current status in Darwin: restricted to 24 hours (same as Instagram).
Behavior: after 24 hours, replies are blocked until the user sends a message.
Meta window: up to 7 days from the user’s last message (pending implementation in Darwin).
Comparison table
Channel | Darwin AI Current Behavior | Meta Session Window | After Session Closes |
24 hours (fully supported) | 24 hours | Can be reopened with a user message or approved template | |
Instagram DM | 24 hours (current limitation) | 7 days | Must wait for user to send a new message |
Facebook Messenger | 24 hours (current limitation) | 7 days | Must wait for user to send a new message |