---
updatedAt: 2025-10-02T13:21:15.000Z
agentTools:
  projectIndex: https://developer.alloy.com/public/llms.txt
---

# Monitoring Events

Depending on your use case, any event can be submitted for additional monitoring by mapping the event type to a [Source Workflow](/docs/ongoing-terminology#source-workflows). When enabled, Alloy stores the data submitted on events and automatically routes all requests for the event type to be evaluated. When taking this approach, you **must** provide the `external_entity_id` or `entity_token`  in your request (along with the [other minimum required fields](https://developer.alloy.com/public/docs/api-request#event-specifications)) so that Alloy can attach the resulting Evaluation and/or Alerts to the correct Entity.

Unlike [data-storing events](/docs/data-storing-events), where only top-level required fields are needed for Alloy schema, additional fields may be required in the `supplemental_data` [section](/docs/api-request#supplemental-data) if you're using 3rd-party services while monitoring.

When a Source Workflow is enabled for an event type, Alloy will return results of the Source Workflow under the `evaluations[]` array in the Events response. If you’re using [ongoing Journeys](/docs/ongoing-terminology#ongoing-journeys), you may also see a record returned in the `journey_applications[]` response section.

As an example, you may perform real-time monitoring on `transaction` events to assess risk and detect suspicious patterns in behavior:

```json Request
{
    "event_type": "transaction",
    "event_lifecycle_id": "e3065d04-95aa-47a1-915c-84b575ff3855",
    "event_status": "completed",
    "data": {
        "external_transaction_id": "e3065d04-95aa-47a1-915c-84b575ff3855",
        "external_account_id": "8b75f5e2-b671-450c-9fb2-5aa05c286309",
        "external_entity_id": "cf88a0a1-34d6-492d-b617-c8b43785e7b7",
        "timestamp": "2023-12-06T13:54:39.735Z",
        "is_approved": true,
        "transaction_created_date": "2023-12-06T13:54:39.735Z",
        "transaction_settled_date": "2023-12-06T13:54:39.735Z",
        "amount": -2000000,
        "process_method": "Cash",
        "category": "Withdrawal",
        "interaction_point": "ATM",
        "description": "NEW YORK NY #238490 WITHDR 12/6",
        "status": "Completed",
        "status_detail": "Completed - Posted",
        "currency": "USD",
        "is_triggered_by_user": false,
        "type_code": "ATM01",
        "type_description": "ATM Cash Withdrawal",
        "counterparty": {
            "external_counterparty_id": "BOA NEW YORK NY #238490",
            "account_type": "merchant account",
            "account_name": "BOA NEW YORK NY #238490 ATM",
            "account_number": "BOA NEW YORK NY #238490",
            "country_code": "US"
        },
        "supplemental_data": {},
        "meta": {}
    }
}
```
```json Response
{
    "status_code": 201,
    "event_request_token": "EV-jalCTa1yXnWqbKYvs05B",
    "_links": {
        "self": {
            "href": "/v1/events/EV-jalCTa1yXnWqbKYvs05B"
        }
    },
    "event": {
        "event_type": "transaction",
        "event_status": "PROCESSED",
        "data": {
            "settled_at": null,
            "description": "NEW YORK NY #238490 WITHDR 12/6",
            "card_process_mode": null,
            "device_type_code": null,
            "type_code": "ATM01",
            "type_description": "ATM Cash Withdrawal",
            "is_approved": true,
            "approval_code": null,
            "is_reversal": null,
            "batch_identifier": "EV-jalCTa1yXnWqbKYvs05B",
            "meta": null,
            "category": "Withdrawal",
            "is_triggered_by_user": false,
            "is_international_override": null,
            "amount": "-2000000",
            "interaction_point": "ATM",
            "status": "Completed",
            "status_detail": "Completed - Posted",
            "process_method": "Cash",
            "return_code": null,
            "return_code_reason": null,
            "entry_mode": null,
            "iso_message": null,
            "response_code": null,
            "archived_at": null,
            "counterparty": {
                "account_type": "merchant account",
                "merchant_category_code": null,
                "account_class": null,
                "country_code": "US",
                "entities": [
                    {
                        "entity_token": "B-4x8WzjvGz5Oz8RWA6MvY"
                    }
                ],
                "account_number": "NEW YORK NY #238490",
                "counterparty_token": "A-vjyYKdRm4Zm8NnRqa9FI"
            },
            "external_account_id": "8b75f5e2-b671-450c-9fb2-5aa05c286309",
            "account_token": "A-Rbdws17NItHaEy3HrHkL",
            "transaction_created_date": "2023-12-06T13:57:58.238Z",
            "currency": "USD",
            "external_transaction_id": "087ac67e-17ab-4529-8d1a-a8b2214d305f"
        },
        "evaluations": [
            {
                "error": null,
                "evaluation_token": "L-l09RgNEuI4qkjfAZLfec",
                "workflow_token": "IO33FzOq7zNRl9XXchWnPAZIXgAUiRwx",
                "workflow_version_id": 2,
                "prefiltered": false,
                "summary": {
                    "result": "success",
                    "outcome": "Needs Investigation",
                    "tags": [
                        "Outgoing",
                        "Anomalous Increase in ATM Withdrawals"
                    ]
                },
                "_links": {
                    "self": {
                        "href": "/v1/evaluations/L-l09RgNEuI4qkjfAZLfec"
                    }
                }
            }
        ],
        "journey_applications": [{
                "error": null,
                "journey_application_token": "JA-EiM42mDnJWlGMR1wSBW2",
                "journey_token": "J-FlFujbCsYMUUiXLl5aEX",
                "journey_version_id": 1,
                "source_evaluation_tokens": [
                    "L-l09RgNEuI4qkjfAZLfec"
                ],
                "_links": {
                    "self": {
                        "href": "/v1/journeys/J-FlFujbCsYMUUiXLl5aEX/applications/JA-EiM42mDnJWlGMR1wSBW2"
                    }
                }
            }]
    }
}
```

<br />

Check out the [Example Scenarios section](/docs/example-ongoing-scenarios) for more common monitoring use cases and to see how monitored events and data-storing events are used together.