| Name | Type | Description | Notes |
|---|---|---|---|
| id | String | Sender's platform identifier. For WhatsApp this is the phone number (without leading `+`) when available, otherwise the `businessScopedUserId`. | |
| name | String | [optional] | |
| username | String | [optional] | |
| picture | String | [optional] | |
| phoneNumber | String | WhatsApp only. Sender's phone number in E.164 format (with leading `+`). Nullable during the BSUID rollout (April 2026+). WhatsApp users who adopt a username can message businesses without exposing a phone number — this field is omitted for them. Match by `businessScopedUserId` instead. See `docs/whatsapp-bsuid-migration.md`. | [optional] |
| businessScopedUserId | String | WhatsApp only. Business-scoped user ID (BSUID) — Meta's canonical identifier for a WhatsApp user within your business. Present when Meta includes it in the inbound payload (rollout in progress since early April 2026). Recommended primary identity anchor going forward; fall back to `phoneNumber` only when this field is absent. | [optional] |
| parentBusinessScopedUserId | String | WhatsApp only. Parent BSUID for businesses with linked business portfolios. Omitted for standalone portfolios. | [optional] |
| whatsappUsername | String | WhatsApp only. User's WhatsApp username (e.g. `@jane`). Not a stable identifier — users can change it. Useful for display, not recommended as an identity anchor. | [optional] |
| instagramProfile | WebhookPayloadMessageMessageSenderInstagramProfile | [optional] |