--- title: Definitions summary: Definitions are used to configure alerts on how to observe a metric. url: >- https://www.fastly.com/documentation/reference/api/observability/alerts/definition --- Definitions are used to configure alerts on how to observe a metric. ## Data model | Field | Type | Description | |-------|------|-------------| | `created_at` | string | Time when the definition was created (RFC3339). (Read-only) | | `description` | string | Additional text that is included in the alert notification. | | `dimensions` | object | More filters depending on the source type. | | `evaluation_strategy` | object | Criteria on how to alert. | | `id` | string | A unique identifier for a definition. (Read-only) | | `integration_ids` | array | List of integrations used to notify when alert fires. Refer to Notification Service. | | `metric` | string | The metric name to alert on for a specific source: domains, origins or stats. | | `name` | string | The name of the alert definition. | | `object` | string | The resource type. (Read-only) | | `service_id` | string | The service on which the definition will alert on. | | `source` | string | The source where the metric comes from. | | `updated_at` | string | Time when the definition was last updated (RFC3339). (Read-only) | ## Data model | Field | Type | Description | |-------|------|-------------| | `compute_resp_status_404_rate` | number | Fraction of Compute responses with 404 codes delivered. If there are no responses, this value will be 0. | | `compute_resp_status_4xx_excl_404_rate` | number | Fraction of Compute responses with non-404 4xx codes delivered. If there are no responses, this value will be 0. | | `compute_resp_status_4xx_rate` | number | Fraction of Compute responses with 4xx codes delivered from domain. If there are no responses, this value will be 0. | | `compute_resp_status_5xx_rate` | number | Fraction of Compute responses with 5xx codes delivered from domain. If there are no responses, this value will be 0. | | `compute_resp_status_gte_400_rate` | number | Fraction of Compute responses with 4xx or 5xx codes delivered from domain. If there are no responses, this value will be 0. | | `compute_resp_status_lt_500_rate` | number | Fraction of Compute responses with non-5xx codes delivered from domain. If there are no responses, this value will be 0. | | `origin_offload_bytes` | number | The number of bytes offloaded to the edge. | | `status_404_rate` | number | Fraction of VCL responses with 404 codes delivered. If there are no responses, this value will be 0. | | `status_4xx_excl_404_rate` | number | Fraction of VCL responses with non-404 4xx codes delivered. If there are no responses, this value will be 0. | | `status_4xx_rate` | number | Fraction of VCL responses with 4xx codes delivered from domain. If there are no responses, this value will be 0. | | `status_5xx_rate` | number | Fraction of VCL responses with 5xx codes delivered from domain. If there are no responses, this value will be 0. | | `status_gte_400_rate` | number | Fraction of VCL responses with 4xx or 5xx codes delivered from domain. If there are no responses, this value will be 0. | | `status_lt_500_rate` | number | Fraction of VCL responses with non-5xx codes delivered from domain. If there are no responses, this value will be 0. | ## Data model | Field | Type | Description | |-------|------|-------------| | `all_bandwidth` | integer | The amount of bandwidth from your origin. | | `all_status_404_rate` | number | Fraction of all responses with 404 codes delivered (Compute, WAF, and VCL). If there are no responses, this value will be 0. | | `all_status_4xx_excl_404_rate` | number | Fraction of all responses with non-404 4xx codes delivered (Compute, WAF, and VCL). If there are no responses, this value will be 0. | | `all_status_4xx_rate` | number | Fraction of all responses with 4xx codes delivered (Compute, WAF, and VCL). If there are no responses, this value will be 0. | | `all_status_5xx_rate` | number | Fraction of all responses with 5xx codes delivered (Compute, WAF, and VCL). If there are no responses, this value will be 0. | | `all_status_gte_400_rate` | number | Fraction of all responses with 4xx or 5xx codes delivered (Compute, WAF, and VCL). If there are no responses, this value will be 0. | | `all_status_lt_500_rate` | number | Fraction of all responses with non-5xx codes delivered (Compute, WAF, and VCL). If there are no responses, this value will be 0. | ## Data model | Field | Type | Description | |-------|------|-------------| | `ignore_below` | number | Threshold for the denominator value used in evaluations that calculate a rate or ratio. Usually used to filter out noise. | | `period` | string | The length of time to evaluate whether the conditions have been met. The data is polled every minute. | | `threshold` | number | Threshold used to alert. | | `type` | string | Type of strategy to use to evaluate. | ## Data model | Field | Type | Description | |-------|------|-------------| | `all_status_4xx_rate` | number | Fraction of all responses with 4xx codes delivered (Compute and VCL). If there are no responses, this value will be 0. | | `all_status_5xx_rate` | number | Fraction of all responses with 5xx codes delivered (Compute and VCL). If there are no responses, this value will be 0. | | `all_status_gte_400_rate` | number | Fraction of all responses with 4xx or 5xx codes delivered (Compute and VCL). If there are no responses, this value will be 0. | | `all_status_lt_500_rate` | number | Fraction of all responses with non-5xx codes delivered (Compute and VCL). If there are no responses, this value will be 0. | | `status_404_rate` | number | Fraction of VCL responses with 404 codes delivered. If there are no responses, this value will be 0. | | `status_4xx_excl_404_rate` | number | Fraction of VCL responses with non-404 4xx codes delivered. If there are no responses, this value will be 0. | | `status_4xx_rate` | number | Fraction of VCL responses with 4xx codes delivered. If there are no responses, this value will be 0. | | `status_5xx_rate` | number | Fraction of VCL responses with 5xx codes delivered. If there are no responses, this value will be 0. | | `status_gte_400_rate` | number | Fraction of VCL responses with 4xx or 5xx codes delivered. If there are no responses, this value will be 0. | | `status_lt_500_rate` | number | Fraction of VCL responses with non-5xx codes delivered. If there are no responses, this value will be 0. | ## API endpoints ### List definitions **GET** `/alerts/definitions` List all definitions for a particular customer. Definitions can be filtered by name, service_id, and integration_id. **Parameters:** | Name | Type | In | Required | Description | |------|------|----|---------|--------------| | `cursor` | string | query | No | Cursor value from the next_cursor field of a previous response, used to retrieve the next page. To request the first page, this should be empty. | | `integration_id` | string | query | No | Filter definitions by integration. | | `limit` | integer | query | No | Limit how many results are returned. | | `name` | string | query | No | Filter definitions by name. | | `service_id` | string | query | No | Filter results based on a service_id. | | `sort` | string | query | No | Sort the items by field provided ascending or descending. | ### Create definition **POST** `/alerts/definitions` Create a definition for a particular customer based on metrics. ### Read definition **GET** `/alerts/definitions/{definition_id}` Retrieve an existing definition by using its ID. **Parameters:** | Name | Type | In | Required | Description | |------|------|----|---------|--------------| | `definition_id` | string | path | Yes | The ID of the definition that is requested. | ### Update definition **PUT** `/alerts/definitions/{definition_id}` Update a definition with a new configuration. **Parameters:** | Name | Type | In | Required | Description | |------|------|----|---------|--------------| | `definition_id` | string | path | Yes | The ID of the definition that is requested. | ### Delete definition **DELETE** `/alerts/definitions/{definition_id}` Delete a definition using its ID. **Parameters:** | Name | Type | In | Required | Description | |------|------|----|---------|--------------| | `definition_id` | string | path | Yes | The ID of the definition that is requested. |