Test notification filter

POST

Evaluates a notification filter against an alert event and returns whether the filter passes.

Use this endpoint to test filter behavior before saving a subscription filter.

This endpoint only evaluates filters. It does not create or update notification subscriptions.

Request modes

• Use eventId when you want to test against an existing stored alert event
• Use event when you want to submit a modified event body for a custom test case

Request body

Field	Type	Required	Description
filter	object	Yes	Filter expression to evaluate
event	object	Conditionally	Event payload to evaluate against
eventId	string	Conditionally	Existing event identifier to load and evaluate
prevEvent	object	No	Previous event payload used when the filter depends on prior state
overrides	object	No	Override values for selected computed max fields during evaluation

Provide either event or eventId.

You can obtain eventId values from the Alerts API event endpoints, such as List alert events and Get alert event.

If you want to provide a custom event body instead of eventId, start from an alert event returned by the Alerts API and modify it for your test case.

Request behavior

• If eventId is provided, the API resolves the event from the caller's environment
• If prevEvent is omitted and eventId resolves to an event with a prior sequence, the API attempts to load the previous event automatically
• overrides can be used to inject test values for computed max fields without changing stored data
• Invalid request bodies return 400
• If eventId is not found, the endpoint returns 404
• Filter evaluation errors return 200 with an error field in the response body

Historical computed values are not populated automatically in this test endpoint

computed values based on historical notification stats are not populated unless you provide them through overrides.

Event-derived computed values, such as current values, previous values, and presence arrays, are still included in the evaluation context.

Response

• 200 OK

Field	Type	Description
pass	boolean	Whether the filter matched the evaluated event
error	string	Present when filter evaluation fails
trace	object	Values resolved for variable paths referenced by the filter; use this to understand why the filter passed or failed
context	object	Full evaluation context used for the filter test

Errors

• 400: invalid request body, invalid filter, invalid eventId, or neither event nor eventId was provided
• 404: eventId not found

Example request

{
  "filter": {
    ">=": [
      {
        "var": "computed.impact.max_24h"
      },
      3
    ]
  },
  "eventId": "alert-123|7",
  "overrides": {
    "impact": {
      "max_24h": 4
    }
  }
}

Example response

{
  "pass": true,
  "trace": {
    "computed.impact.max_24h": 4
  },
  "context": {
    "event": {},
    "computed": {
      "impact": {
        "max_24h": 4
      }
    }
  }
}