💬 Facebook Messenger
Connect a Facebook Page Messenger account to send + receive messages from inside Synalux.
📨 Messenger Send / Receive
- Webhook —
/api/v1/messenger/webhookreceives Page-bound messages; Meta signature validated. - Send —
/api/v1/messenger/sendposts to Meta's/me/messagesendpoint withappsecret_proofHMAC-SHA256 protection on every call (defense against access-token leak). - Page-scoped — one Facebook Page connection per workspace.
- 24-hour window + tags — outbound after 24h must use
MESSAGE_TAGper Meta policy.

🔐 App Review
For Meta App Review, Synalux exposes admin endpoints to fire test calls per requested permission so the App Review counter increments:
POST /api/v1/messenger/admin/test-send Fire a test message (CRON_SECRET-gated)
POST /api/v1/messenger/admin/test-all-permissions One Graph API call per requested permission
This is what gets you through Meta App Review's "exercise the API" requirement without scripting it manually.
🏗️ Architecture
POST /api/v1/messenger/webhook Meta webhook (signature-validated)
POST /api/v1/messenger/send Outbound message (appsecret_proof on every call)
POST /api/v1/messenger/admin/test-* App Review counter exercises
💳 Plans
Available on Standard+.