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Webhook Subscriptions

Create a new webhook subscription

POST/v3/webhook-subscriptions

Create a new webhook subscription to receive events at a target URL. Upon creation, a signing secret is generated for verifying webhook authenticity. Store this secret securely — it cannot be retrieved later.

Phone Number Filtering:

  • Optionally specify phone_numbers to only receive events for specific lines
  • If omitted, events from all phone numbers are delivered (default behavior)
  • Use multiple subscriptions with different phone_numbers to route different lines to different endpoints
  • Each target_url can only be used once per account. To route different lines to different destinations, use a unique URL per subscription (e.g., append a query parameter: https://example.com/webhook?line=1)

Webhook Delivery:

  • Events are sent via HTTP POST to the target URL
  • Each request includes Standard Webhooks headers (webhook-id, webhook-timestamp, webhook-signature) for signature verification
  • Legacy X-Webhook-* headers are also sent for backwards compatibility (deprecated)
  • See Verifying Webhook Signatures for verification details
  • Failed deliveries (5xx, 429, network errors) are retried with exponential backoff for up to 30 minutes
  • Client errors (4xx except 429) are not retried
Body ParametersJSONExpand Collapse
subscribed_events: array of WebhookEventType

List of event types to subscribe to

One of the following:
"message.sent"
"message.received"
"message.read"
"message.delivered"
"message.failed"
"message.edited"
"reaction.added"
"reaction.removed"
"poll.received"
"poll.failed"
"poll.sent"
"poll.delivered"
"poll.read"
"poll.updated"
"poll.vote.added"
"poll.vote.removed"
"poll.reaction.added"
"participant.added"
"participant.removed"
"chat.created"
"chat.group_name_updated"
"chat.group_icon_updated"
"chat.group_name_update_failed"
"chat.group_icon_update_failed"
"chat.background_updated"
"chat.background_update_failed"
"chat.typing_indicator.started"
"chat.typing_indicator.stopped"
"phone_number.status_updated"
"phone_number.assigned"
"phone_number.released"
"contact_card.received"
"call.initiated"
"call.ringing"
"call.answered"
"call.ended"
"call.failed"
"call.declined"
"call.no_answer"
"location.sharing.started"
"location.sharing.stopped"
"payment.succeeded"
"payment.canceled"
"payment.expired"
"payment.declined"
"payment.authorized"
"connection.created"
"connection.revoked"
"zero_day_retention.updated"
"phone_number.forwarding_updated"
"environment.line_moved"
"contact_card.created"
"contact_card.updated"
"contact_card.deleted"
"api_token.created"
"api_token.renamed"
"api_token.expiry_scheduled"
"api_token.expired"
"api_token.activated"
"api_token.deleted"
"environment.created"
"environment.renamed"
"environment.deleted"
"webhook_subscription.created"
"webhook_subscription.deleted"
"webhook_subscription.target_url_changed"
"webhook_subscription.enabled"
"webhook_subscription.disabled"
"webhook_subscription.events.updated"
"webhook_subscription.phone_numbers.updated"
"webhook_subscription.routing_headers_set"
"webhook_subscription.routing_headers_cleared"
"team_member.added"
"team_member.signed_in"
"team_member.signed_out"
target_url: string

URL where webhook events will be sent. Must be HTTPS.

formaturi
phone_numbers: optional array of string

Optional list of phone numbers to filter events for. Only events originating from these phone numbers will be delivered to this subscription. If omitted or empty, events from all phone numbers are delivered. Phone numbers must be in E.164 format.

routing_id_header: optional string

Name of the header carrying the chat id, used to hash-route before a token is learned. Defaults to Linq-Chat-Id. Ignored without routing_key_header.

routing_key_header: optional string

Enables delivery affinity. Name of the header carrying an opaque routing token: we send it on each webhook for a chat and read it back from your 2xx response, so your edge can route to the cluster holding that chat. Omit to disable.

ReturnsExpand Collapse
id: string

Unique identifier for the webhook subscription

created_at: string

When the subscription was created

formatdate-time
is_active: boolean

Whether this subscription is currently active

signing_secret: string

Secret for verifying webhook signatures. Store this securely - it cannot be retrieved again.

subscribed_events: array of WebhookEventType

List of event types this subscription receives

One of the following:
"message.sent"
"message.received"
"message.read"
"message.delivered"
"message.failed"
"message.edited"
"reaction.added"
"reaction.removed"
"poll.received"
"poll.failed"
"poll.sent"
"poll.delivered"
"poll.read"
"poll.updated"
"poll.vote.added"
"poll.vote.removed"
"poll.reaction.added"
"participant.added"
"participant.removed"
"chat.created"
"chat.group_name_updated"
"chat.group_icon_updated"
"chat.group_name_update_failed"
"chat.group_icon_update_failed"
"chat.background_updated"
"chat.background_update_failed"
"chat.typing_indicator.started"
"chat.typing_indicator.stopped"
"phone_number.status_updated"
"phone_number.assigned"
"phone_number.released"
"contact_card.received"
"call.initiated"
"call.ringing"
"call.answered"
"call.ended"
"call.failed"
"call.declined"
"call.no_answer"
"location.sharing.started"
"location.sharing.stopped"
"payment.succeeded"
"payment.canceled"
"payment.expired"
"payment.declined"
"payment.authorized"
"connection.created"
"connection.revoked"
"zero_day_retention.updated"
"phone_number.forwarding_updated"
"environment.line_moved"
"contact_card.created"
"contact_card.updated"
"contact_card.deleted"
"api_token.created"
"api_token.renamed"
"api_token.expiry_scheduled"
"api_token.expired"
"api_token.activated"
"api_token.deleted"
"environment.created"
"environment.renamed"
"environment.deleted"
"webhook_subscription.created"
"webhook_subscription.deleted"
"webhook_subscription.target_url_changed"
"webhook_subscription.enabled"
"webhook_subscription.disabled"
"webhook_subscription.events.updated"
"webhook_subscription.phone_numbers.updated"
"webhook_subscription.routing_headers_set"
"webhook_subscription.routing_headers_cleared"
"team_member.added"
"team_member.signed_in"
"team_member.signed_out"
target_url: string

URL where webhook events will be sent

formaturi
updated_at: string

When the subscription was last updated

formatdate-time
phone_numbers: optional array of string

Phone numbers this subscription filters for. If null or empty, events from all phone numbers are delivered.

routing_id_header: optional string

Header carrying the chat id. Defaults to Linq-Chat-Id when affinity is on.

routing_key_header: optional string

Header carrying the routing token. Null disables delivery affinity.

Create a new webhook subscription

curl https://api.linqapp.com/api/partner/v3/webhook-subscriptions \
    -H 'Content-Type: application/json' \
    -H "Authorization: Bearer $LINQ_API_V3_API_KEY" \
    -d '{
          "subscribed_events": [
            "message.sent",
            "message.delivered",
            "message.read"
          ],
          "target_url": "https://webhooks.example.com/linq/events",
          "phone_numbers": [
            "+12025551234",
            "+12025559876"
          ],
          "routing_id_header": "X-Chat-Id",
          "routing_key_header": "X-Route-Token"
        }'
{
  "id": "b2c3d4e5-f6a7-8901-bcde-f23456789012",
  "created_at": "2024-01-15T10:30:00Z",
  "is_active": true,
  "signing_secret": "whsec_abc123def456",
  "subscribed_events": [
    "message.sent",
    "message.delivered",
    "message.read"
  ],
  "target_url": "https://webhooks.example.com/linq/events",
  "updated_at": "2024-01-15T10:30:00Z",
  "phone_numbers": [
    "string"
  ],
  "routing_id_header": "X-Chat-Id",
  "routing_key_header": "X-Route-Token"
}
{
  "error": {
    "status": 400,
    "code": 1002,
    "message": "Phone number must be in E.164 format",
    "doc_url": "https://docs.linqapp.com/channel/imessage/error/codes/1xxx/1002/"
  },
  "success": false
}
{
  "error": {
    "status": 401,
    "code": 2004,
    "message": "Unauthorized - missing or invalid authentication token",
    "doc_url": "https://docs.linqapp.com/channel/imessage/error/codes/2xxx/2004/"
  },
  "success": false
}
{
  "error": {
    "status": 500,
    "code": 3006,
    "message": "Internal server error",
    "doc_url": "https://docs.linqapp.com/channel/imessage/error/codes/3xxx/3006/"
  },
  "success": false
}
Returns Examples
{
  "id": "b2c3d4e5-f6a7-8901-bcde-f23456789012",
  "created_at": "2024-01-15T10:30:00Z",
  "is_active": true,
  "signing_secret": "whsec_abc123def456",
  "subscribed_events": [
    "message.sent",
    "message.delivered",
    "message.read"
  ],
  "target_url": "https://webhooks.example.com/linq/events",
  "updated_at": "2024-01-15T10:30:00Z",
  "phone_numbers": [
    "string"
  ],
  "routing_id_header": "X-Chat-Id",
  "routing_key_header": "X-Route-Token"
}
{
  "error": {
    "status": 400,
    "code": 1002,
    "message": "Phone number must be in E.164 format",
    "doc_url": "https://docs.linqapp.com/channel/imessage/error/codes/1xxx/1002/"
  },
  "success": false
}
{
  "error": {
    "status": 401,
    "code": 2004,
    "message": "Unauthorized - missing or invalid authentication token",
    "doc_url": "https://docs.linqapp.com/channel/imessage/error/codes/2xxx/2004/"
  },
  "success": false
}
{
  "error": {
    "status": 500,
    "code": 3006,
    "message": "Internal server error",
    "doc_url": "https://docs.linqapp.com/channel/imessage/error/codes/3xxx/3006/"
  },
  "success": false
}
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