Customer.io · Schema
Webhook
For webhooks, you must include `body`, `request_method`, and `url`.
Behavioral DataBroadcastCampaignsCDPCustomer DataCustomer Data PlatformData IngestionEmailEvent TrackingMarketing AutomationMessagingPush NotificationsSegmentsSMSTransactional EmailA2A
JSON Schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"$id": "https://raw.githubusercontent.com/api-evangelist/customer-io/main/json-schema/customer-io-create-webhook-newsletter-schema.json",
"title": "Webhook",
"description": "For webhooks, you must include `body`, `request_method`, and `url`.",
"x-generated": "2026-10-12",
"x-method": "derived",
"x-generator": "derive-json-schema.py",
"x-source": "openapi/customer-io-newsletters-api-openapi.yml#/components/schemas/createWebhookNewsletter",
"allOf": [
{
"type": "object",
"required": [
"name",
"type",
"recipients"
],
"properties": {
"name": {
"type": "string",
"maxLength": 190,
"description": "The name of the newsletter."
},
"recipients": {
"type": "object",
"description": "Filter conditions that define the newsletter's recipients. Combine `segment` and `attribute` conditions with `and`, `or`, and `not` operators.\n",
"properties": {
"and": {
"type": "array",
"description": "An array of conditions that must all be true.",
"items": {
"type": "object"
}
},
"or": {
"type": "array",
"description": "An array of conditions where at least one must be true.",
"items": {
"type": "object"
}
},
"not": {
"type": "object",
"description": "A condition or group of conditions to exclude."
},
"segment": {
"type": "object",
"description": "A segment condition.",
"properties": {
"id": {
"type": "integer",
"description": "The ID of a segment."
}
}
},
"attribute": {
"type": "object",
"description": "A customer attribute condition.",
"properties": {
"field": {
"type": "string",
"description": "The attribute name."
},
"operator": {
"type": "string",
"description": "The comparison operator.",
"enum": [
"eq",
"exists"
]
},
"value": {
"type": "string",
"description": "The value to compare against. Required when `operator` is `eq`."
},
"inverse": {
"type": "boolean",
"description": "Set to `true` for \"is not equal\" or \"does not exist\"."
}
}
}
}
},
"send_now": {
"type": "boolean",
"description": "If `true`, the newsletter is sent immediately after creation. You cannot set both `send_now` and `scheduled_at`."
},
"scheduled_at": {
"type": "integer",
"format": "unix timestamp",
"description": "A Unix timestamp indicating when to send the newsletter. The time must be in the future. You cannot set both `send_now` and `scheduled_at`."
},
"subscription_topic_id": {
"type": "integer",
"description": "The newsletter audience's subscription topic ID. Required when [subscription center](/journeys/channels/subscriptions/center/#enable-sub-center) is enabled; otherwise sends to globally subscribed profiles."
}
}
},
{
"type": "object",
"description": "Optional newsletter rate limiting. If you set `rate_limit_email_rate` or `rate_limit_time_period`, set both; `rate_limit_spread` can be set alone.",
"properties": {
"rate_limit_email_rate": {
"type": "integer",
"minimum": 1,
"description": "Maximum number of messages per time period. **NOTE:** Though this states `email_rate`, you can use this for other message channels. Only fixed rate limits are supported, not [daily ramp limits](/journeys/send/broadcasts/newsletters/#daily-ramp).\n"
},
"rate_limit_time_period": {
"type": "integer",
"enum": [
60,
3600,
86400
],
"description": "Time period in seconds for rate limiting. Must be one of 60 (minute), 3600 (hour), or 86400 (day)."
},
"rate_limit_spread": {
"type": "boolean",
"description": "When `true`, spreads messages evenly across the time period. Otherwise, it sends as fast as possible up to the limit in each period."
}
}
},
{
"type": "object",
"required": [
"body",
"request_method",
"url"
],
"properties": {
"type": {
"type": "string",
"description": "The channel type for the newsletter.",
"enum": [
"webhook"
]
},
"body": {
"type": "string",
"description": "The body content of the webhook request."
},
"request_method": {
"type": "string",
"description": "The HTTP method for the webhook request.",
"enum": [
"DELETE",
"GET",
"POST",
"PUT",
"PATCH"
]
},
"url": {
"type": "string",
"description": "The URL to send the webhook request to."
}
}
}
]
}
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