> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nippy.la/llms.txt
> Use this file to discover all available pages before exploring further.

# track()

> Send a business event and evaluate campaign rules

`track()` records a business event and evaluates whether any campaign rule should trigger a mechanic.

## Usage

<CodeGroup>
  ```typescript TypeScript theme={null}
  const result = await nippy.track({
    userId: 'user-123',
    campaignId: 'camp-abc',
    eventType: 'card.purchase.completed',
    properties: { value: 500 },
    occurredAt: new Date().toISOString()
  })
  ```

  ```bash curl theme={null}
  curl -X POST https://ms.nippy.la/v1/public/events/track \
    -H "x-api-key: npk_live_xxx" \
    -H "Content-Type: application/json" \
    -d '{
      "userId": "user-123",
      "campaignId": "camp-abc",
      "eventType": "card.purchase.completed",
      "properties": { "value": 500 },
      "occurredAt": "2026-05-01T12:00:00.000Z"
    }'
  ```
</CodeGroup>

## Parameters

<ParamField body="userId" type="string" required>
  User identifier from your system. Example: `user-123`.
</ParamField>

<ParamField body="campaignId" type="string" required>
  Campaign ID that should evaluate the event. Example: `camp-abc`.
</ParamField>

<ParamField body="eventType" type="string" required>
  Event type configured in the rule. Example: `card.purchase.completed`.
</ParamField>

<ParamField body="properties" type="object" default="{}">
  Event data used by rule conditions. Example: `{ "value": 500 }`.
</ParamField>

<ParamField body="occurredAt" type="string" default="request receipt time">
  ISO 8601 timestamp for when the event occurred.
</ParamField>

## Response

<ResponseField name="triggered" type="array">
  Mechanics triggered by the event. Empty when no rule matched.
</ResponseField>

<ResponseField name="triggered[].spinId" type="string">
  ID of the triggered spin.
</ResponseField>

<ResponseField name="triggered[].campaignId" type="string">
  Campaign ID that triggered the spin.
</ResponseField>

<ResponseField name="triggered[].ruleId" type="string">
  Rule ID that triggered the spin.
</ResponseField>

<Note>
  `track()` does not return the spin result. The result arrives through the `spin.completed` webhook.
</Note>