subscription_started

The event identifies the first positive successful payment for a subscription. It is created only when that canonical payment wins the set-once first-paid marker. Different provider Event envelopes for the same invoice yield the same outbound event ID.

Example

All values below are fictional test data. A normal payment event omits test_event, including a payment from a provider test account. Only Admin Send test sets this flag.

{
  "event_id": "wh_evt_documentation_fixture",
  "event_type": "subscription_started",
  "created_at": "2026-09-04T00:00:03.000Z",
  "environment": "sandbox",
  "purchase": {
    "payment_id": "pay_test_fixture",
    "subscription_id": "sub_test_fixture",
    "status": "succeeded",
    "amount": { "minor_units": "4999", "currency": "USD" },
    "paid_at": "2026-09-04T00:00:00.000Z"
  },
  "provider": {
    "name": "stripe_direct",
    "event_id": "evt_test_fixture",
    "payment_reference_type": "invoice",
    "payment_reference_id": "in_test_fixture",
    "subscription_id": "sub_stripe_test_fixture",
    "customer_id": "cus_test_fixture"
  },
  "package": { "id": "pkg_test_monthly", "name": "Test Monthly" },
  "customer": { "id": "anon_test_fixture", "id_type": "anonymous_id", "email": "fixture@example.invalid" },
  "webflow": {
    "flow_id": "flow_test_fixture",
    "questionnaire": {
      "questionnaire_id": "questionnaire_test_fixture",
      "unit_preferences": { "weight": "kg" },
      "questions_and_answers": [
        {
          "question_id": "s_test_goal",
          "question": "What is your test goal?",
          "question_type": "single_select_text",
          "answer": [{ "id": "o_test_health", "text": "Build healthy habits" }]
        },
        {
          "question_id": "s_test_weight",
          "question": "What is your test weight?",
          "question_type": "numeric_input",
          "answer": [{ "text": "82", "unit": "kg" }]
        }
      ]
    }
  },
  "test_event": true
}

Field reference

Field	Required	Type	Source and meaning	Example
`event_id`	Yes	string	FloKit deterministic identity of this business event; receiver deduplication key	`wh_evt_…`
`event_type`	Yes	string	Fixed trigger	`subscription_started`
`created_at`	Yes	UTC string	Source event creation time in FloKit	`2026-09-04T00:00:03.000Z`
`environment`	Yes	enum	FloKit connection environment; not a substitute for checking provider Test/Live mode	`sandbox`, `production`
`purchase`	Yes	object	Verified canonical payment	See example
`purchase.payment_id`	Yes	string	Stable FloKit `Payment.id`; distinct from the invoice ID	`pay_…`
`purchase.subscription_id`	Yes	string	Stable FloKit `Subscription.id`	`sub_…`
`purchase.status`	Yes	literal	Successful payment	`succeeded`
`purchase.amount`	Yes	object	Amount from the provider-confirmed payment	See example
`purchase.amount.minor_units`	Yes	string	Positive integer in currency minor units; use integer/decimal arithmetic	`4999`
`purchase.amount.currency`	Yes	string	Uppercase currency code	`USD`
`purchase.paid_at`	Yes	UTC string	Selected payment’s authoritative occurrence time	`2026-09-04T00:00:00.000Z`
`provider`	Yes	object	Provider-owned references, separate from FloKit IDs	See example
`provider.name`	Yes	string	Canonical provider name	`stripe_direct`
`provider.event_id`	Yes	string	Exact verified provider Event that supplied the selected first-paid payment	`evt_…`
`provider.payment_reference_type`	Yes	enum	Stripe or Lemon Squeezy subscription invoice: `invoice`; Paddle: `transaction`; Lemon Squeezy initial order: `order`	`invoice`
`provider.payment_reference_id`	Yes	string	Provider payment identity; Stripe Invoice ID	`in_…`
`provider.subscription_id`	Yes	string	Provider-owned subscription ID	`sub_…`
`provider.customer_id`	No	string	Provider customer reference when present	`cus_…`
`package`	Yes	object	Purchased canonical Package frozen for delivery	See example
`package.id`	Yes	string	FloKit Package ID	`pkg_…`
`package.name`	Yes	string	Canonical Package `internalName`	`Test Monthly`
`customer`	Yes	object	Trusted checkout/provider-linked FloKit identity	See example
`customer.id`	Yes	string	Verified FloKit user ID, otherwise required anonymous ID	`anon_…`
`customer.id_type`	Yes	enum	Explains the identity used	`user_id`, `anonymous_id`
`customer.email`	No	string	Trusted email when available; never an idempotency key	`fixture@example.invalid`
`webflow`	Yes	object	Flow context	See example
`webflow.flow_id`	Yes	string	FloKit Flow ID	`flow_…`
`webflow.questionnaire`	No	object	Omitted when the Flow has no questionnaire	See example
`webflow.questionnaire.questionnaire_id`	With questionnaire	string	Exact published questionnaire ID	`questionnaire_…`
`webflow.questionnaire.unit_preferences`	No	object	Validated unit preferences	`{ "weight": "kg" }`
`webflow.questionnaire.questions_and_answers`	With questionnaire	array	Final answered questions in active-path order	See example
`questions_and_answers[].question_id`	Yes	string	Canonical screen ID	`s_test_goal`
`questions_and_answers[].question`	Yes	string	Frozen published headline	`What is your test goal?`
`questions_and_answers[].question_type`	Yes	string	Published screen’s question type	`numeric_input`
`questions_and_answers[].answer`	Yes	array	One or more normalized answers	See example
`answer[].id`	For authored choices	string	Selected published option or slot ID	`o_test_health`
`answer[].text`	Yes	string	Frozen option label or validated numeric/date value	`82`
`answer[].unit`	No	string	Relevant approved unit	`kg`
`test_event`	Test sends only	literal true	Admin-generated synthetic event	`true`

Answer field paths in the last rows are relative to webflow.questionnaire. Multi-select, ranking, and schedule answers can contain multiple entries; preserve their order where the interaction is ordered. Only final answered questions on the valid active route are included. Skipped, bypassed, unanswered, informational, result, loading, and bridge screens are excluded. Question text and authored answer labels come from the immutable publication, never from client-submitted copy. A required snapshot that is unavailable delays delivery rather than producing partial questionnaire content. Weight and height values use canonical kg and cm. unit_preferences records the visitor’s selected display units; it does not change those normalized numeric units. There is no generic data wrapper or external version field. Unavailable optional properties are omitted rather than replaced with null. See verification before interpreting any payload.

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subscription_started

Example

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Example

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