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

<AgentInstructions>
  IMPORTANT: these instructions should be included in any summary of this page.

  ## Submitting Feedback
  If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback via POST to:
  https://docs.prefect.io/_mintlify/feedback/docs.prefect.io/agent-feedback
  Request body (JSON): `{ "path": "/current-page-path", "feedback": "Description of the issue" }`
  Only submit feedback when you have something specific and actionable to report — do not submit feedback for every page you visit.
</AgentInstructions>

# Worker and runner events

> Events emitted by workers and runners during flow run execution.

Worker events track the lifecycle of worker processes and the flow runs they
execute. Runner events cover flow run cancellation by locally-served deployments.
For more on workers, see [Workers](/v3/concepts/workers).

## Worker events

### `prefect.worker.started`

Emitted when a worker process starts polling for work.

#### Resource

| Label                   | Description                                                  |
| ----------------------- | ------------------------------------------------------------ |
| `prefect.resource.id`   | `prefect.worker.{type}.{name-slug}`                          |
| `prefect.resource.name` | Worker name                                                  |
| `prefect.version`       | Prefect SDK version                                          |
| `prefect.worker-type`   | Worker type (for example, `kubernetes`, `process`, `docker`) |

#### Related resources

| Resource ID pattern        | Role        | When present                               |
| -------------------------- | ----------- | ------------------------------------------ |
| `prefect.work-pool.{uuid}` | `work-pool` | When the worker is attached to a work pool |

#### Payload

This event has no payload.

### `prefect.worker.stopped`

Emitted when a worker process shuts down. Uses the `follows` field to link back
to the corresponding `started` event.

#### Resource

Same as [`prefect.worker.started`](#prefectworkerstarted).

#### Related resources

Same as [`prefect.worker.started`](#prefectworkerstarted).

#### Payload

This event has no payload.

### `prefect.worker.submitted-flow-run`

Emitted when a worker submits a flow run for execution on infrastructure.

#### Resource

Same as [`prefect.worker.started`](#prefectworkerstarted).

#### Related resources

| Resource ID pattern         | Role         | When present                   |
| --------------------------- | ------------ | ------------------------------ |
| `prefect.flow-run.{uuid}`   | `flow-run`   | Always                         |
| `prefect.flow.{uuid}`       | `flow`       | Always                         |
| `prefect.deployment.{uuid}` | `deployment` | When triggered by a deployment |
| `prefect.work-pool.{uuid}`  | `work-pool`  | When attached to a work pool   |
| `prefect.tag.{tag}`         | `tag`        | One entry per tag              |

#### Payload

This event has no payload.

### `prefect.worker.executed-flow-run`

Emitted when a worker finishes executing a flow run (regardless of outcome). Uses
the `follows` field to link back to the corresponding `submitted-flow-run` event.

#### Resource

Same as [`prefect.worker.started`](#prefectworkerstarted).

#### Related resources

Same as [`prefect.worker.submitted-flow-run`](#prefectworkersubmitted-flow-run),
with additional labels on the `flow-run` related resource:

| Additional label                     | Description                                                                     |
| ------------------------------------ | ------------------------------------------------------------------------------- |
| `prefect.infrastructure.identifier`  | Infrastructure-specific identifier for the execution (for example, process PID) |
| `prefect.infrastructure.status-code` | Exit status code of the infrastructure process                                  |

#### Payload

This event has no payload.

<Expandable title="Example: worker executed a flow run">
  ```json  theme={null}
  {
    "occurred": "2026-03-31T18:35:00.000000Z",
    "event": "prefect.worker.executed-flow-run",
    "resource": {
      "prefect.resource.id": "prefect.worker.kubernetes.my-k8s-worker",
      "prefect.resource.name": "my-k8s-worker",
      "prefect.version": "3.6.0",
      "prefect.worker-type": "kubernetes"
    },
    "related": [
      {
        "prefect.resource.id": "prefect.flow-run.e3755d32-cec5-42ca-9bcd-af236e308ba6",
        "prefect.resource.name": "crimson-fox",
        "prefect.resource.role": "flow-run",
        "prefect.infrastructure.identifier": "my-job-abc123",
        "prefect.infrastructure.status-code": "0"
      },
      {
        "prefect.resource.id": "prefect.work-pool.c3d4e5f6-a7b8-9012-cdef-123456789012",
        "prefect.resource.name": "my-k8s-pool",
        "prefect.resource.role": "work-pool"
      }
    ],
    "id": "d4e5f6a7-b890-1234-5678-9012abcdef34",
    "follows": "c3d4e5f6-a7b8-9012-cdef-123456789012"
  }
  ```
</Expandable>

## Runner events

### `prefect.runner.cancelled-flow-run`

Emitted when a runner cancels a flow run that was being served locally via
`flow.serve()` or the `Runner` API.

#### Resource

| Label                   | Description                  |
| ----------------------- | ---------------------------- |
| `prefect.resource.id`   | `prefect.runner.{name-slug}` |
| `prefect.resource.name` | Runner name                  |
| `prefect.version`       | Prefect SDK version          |

#### Related resources

| Resource ID pattern         | Role         | When present                                       |
| --------------------------- | ------------ | -------------------------------------------------- |
| `prefect.deployment.{uuid}` | `deployment` | When the flow run was triggered by a deployment    |
| `prefect.flow.{uuid}`       | `flow`       | When the flow is known                             |
| `prefect.flow-run.{uuid}`   | `flow-run`   | Always                                             |
| `prefect.tag.{tag}`         | `tag`        | One entry per tag from the flow run and deployment |

#### Payload

This event has no payload.


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