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

# Events reference

> Reference for all events emitted by Prefect, Prefect Cloud, and integrations.

This section catalogs every event that Prefect emits, organized by the resource type they
concern. For a conceptual overview of events, resources, and related resources, see
[Events](/docs/v3/concepts/events.md).

## Event model

Every event follows this schema:

| Field | Type | Required | Description |
| - | - | - | - |
| `occurred` | datetime | yes | When the event happened |
| `event` | string | yes | Name of the event (for example, `prefect.flow-run.Running`) |
| `resource` | object | yes | Primary [resource](#resources) this event concerns |
| `related` | array | no | Additional [related resources](#related-resources) involved in this event |
| `payload` | object | no | Open-ended data describing what happened |
| `id` | UUID | yes | Client-provided identifier for this event |
| `follows` | UUID | no | ID of a preceding event, used to establish ordering |

## Resources

Every event has a primary resource represented as a set of string key-value labels. Every
resource must include `prefect.resource.id`, a dot-delimited quasi-stable identifier like
`prefect.flow-run.e3755d32-cec5-42ca-9bcd-af236e308ba6`. Resources may also carry
`prefect.resource.name` and any number of additional labels.

## Related resources

Events may include related resources that provide context about other objects involved. Each
related resource carries all the same labels as a resource, plus a required
`prefect.resource.role` label describing its relationship to the event (for example, `flow`,
`deployment`, `work-pool`, or `tag`).

## Namespace conventions

Prefect uses dot-delimited event names with reserved prefixes for system-emitted
events:

| Prefix | Origin |
| - | - |
| `prefect.*` | Prefect open source (OSS) and Prefect server |
| `prefect-cloud.*` | Prefect Cloud only |
| `prefect.docker.*` | prefect-docker integration |
| `prefect.kubernetes.*` | prefect-kubernetes integration |
| `prefect.ecs.*` | prefect-aws integration (ECS observer) |

The `prefect.*` and `prefect-cloud.*` namespaces are reserved for events emitted
by Prefect itself. Your own events can use any other namespace you like. For
example, `acme.data-pipeline.completed` or `myteam.model.trained` are perfectly
valid event names. See [custom event grammar](/docs/v3/advanced/use-custom-event-grammar.md)
for more on emitting your own events.

## Quick reference

### Orchestration events

| Event | Description | Page |
| - | - | - |
| `prefect.flow-run.{state}` | Flow run state transitions | [Flow run events](/docs/v3/api-ref/events/flow-run-events.md) |
| `prefect.flow-run.heartbeat` | Periodic flow run liveness signal | [Flow run events](/docs/v3/api-ref/events/flow-run-events.md) |
| `prefect.task-run.{state}` | Task run state transitions | [Task run events](/docs/v3/api-ref/events/task-run-events.md) |
| `prefect.deployment.created` | Deployment created | [Deployment events](/docs/v3/api-ref/events/deployment-events.md) |
| `prefect.deployment.updated` | Deployment fields changed | [Deployment events](/docs/v3/api-ref/events/deployment-events.md) |
| `prefect.deployment.deleted` | Deployment deleted | [Deployment events](/docs/v3/api-ref/events/deployment-events.md) |
| `prefect.deployment.{status}` | Deployment status transitions | [Deployment events](/docs/v3/api-ref/events/deployment-events.md) |
| `prefect.work-pool.created` | Work pool created | [Work pool and queue events](/docs/v3/api-ref/events/work-pool-queue-events.md) |
| `prefect.work-pool.deleted` | Work pool deleted | [Work pool and queue events](/docs/v3/api-ref/events/work-pool-queue-events.md) |
| `prefect.work-pool.{status}` | Work pool status transitions | [Work pool and queue events](/docs/v3/api-ref/events/work-pool-queue-events.md) |
| `prefect.work-pool.updated` | Work pool fields changed | [Work pool and queue events](/docs/v3/api-ref/events/work-pool-queue-events.md) |
| `prefect.work-queue.created` | Work queue created | [Work pool and queue events](/docs/v3/api-ref/events/work-pool-queue-events.md) |
| `prefect.work-queue.deleted` | Work queue deleted | [Work pool and queue events](/docs/v3/api-ref/events/work-pool-queue-events.md) |
| `prefect.work-queue.{status}` | Work queue status transitions | [Work pool and queue events](/docs/v3/api-ref/events/work-pool-queue-events.md) |
| `prefect.work-queue.updated` | Work queue fields changed | [Work pool and queue events](/docs/v3/api-ref/events/work-pool-queue-events.md) |

### Execution events

| Event | Description | Page |
| - | - | - |
| `prefect.worker.started` | Worker process started | [Worker and runner events](/docs/v3/api-ref/events/worker-runner-events.md) |
| `prefect.worker.stopped` | Worker process stopped | [Worker and runner events](/docs/v3/api-ref/events/worker-runner-events.md) |
| `prefect.worker.submitted-flow-run` | Worker submitted a flow run | [Worker and runner events](/docs/v3/api-ref/events/worker-runner-events.md) |
| `prefect.worker.executed-flow-run` | Worker finished executing a flow run | [Worker and runner events](/docs/v3/api-ref/events/worker-runner-events.md) |
| `prefect.runner.cancelled-flow-run` | Runner cancelled a flow run | [Worker and runner events](/docs/v3/api-ref/events/worker-runner-events.md) |

### Data events

| Event | Description | Page |
| - | - | - |
| `prefect.artifact-collection.created` | Artifact collection created | [Artifact and asset events](/docs/v3/api-ref/events/artifact-asset-events.md) |
| `prefect.artifact-collection.updated` | Artifact collection latest version changed | [Artifact and asset events](/docs/v3/api-ref/events/artifact-asset-events.md) |
| `prefect.artifact-collection.deleted` | Artifact collection deleted | [Artifact and asset events](/docs/v3/api-ref/events/artifact-asset-events.md) |
| `prefect.artifact.created` | Individual artifact created | [Artifact and asset events](/docs/v3/api-ref/events/artifact-asset-events.md) |
| `prefect.artifact.updated` | Individual artifact updated | [Artifact and asset events](/docs/v3/api-ref/events/artifact-asset-events.md) |
| `prefect.asset.referenced` | Upstream asset referenced | [Artifact and asset events](/docs/v3/api-ref/events/artifact-asset-events.md) |
| `prefect.asset.materialization.succeeded` | Asset materialization succeeded | [Artifact and asset events](/docs/v3/api-ref/events/artifact-asset-events.md) |
| `prefect.asset.materialization.failed` | Asset materialization failed | [Artifact and asset events](/docs/v3/api-ref/events/artifact-asset-events.md) |

### Concurrency events

| Event | Description | Page |
| - | - | - |
| `prefect.concurrency-limit.created` | Concurrency limit created | [Concurrency events](/docs/v3/api-ref/events/concurrency-events.md) |
| `prefect.concurrency-limit.updated` | Concurrency limit configuration changed | [Concurrency events](/docs/v3/api-ref/events/concurrency-events.md) |
| `prefect.concurrency-limit.deleted` | Concurrency limit deleted | [Concurrency events](/docs/v3/api-ref/events/concurrency-events.md) |
| `prefect.concurrency-limit.acquired` | Concurrency slots acquired | [Concurrency events](/docs/v3/api-ref/events/concurrency-events.md) |
| `prefect.concurrency-limit.released` | Concurrency slots released | [Concurrency events](/docs/v3/api-ref/events/concurrency-events.md) |

### Automation events

| Event | Description | Page |
| - | - | - |
| `prefect.automation.created` | Automation created | [Automation events](/docs/v3/api-ref/events/automation-events.md) |
| `prefect.automation.updated` | Automation updated | [Automation events](/docs/v3/api-ref/events/automation-events.md) |
| `prefect.automation.deleted` | Automation deleted | [Automation events](/docs/v3/api-ref/events/automation-events.md) |
| `prefect.automation.triggered` | Automation trigger fired | [Automation events](/docs/v3/api-ref/events/automation-events.md) |
| `prefect.automation.resolved` | Automation trigger resolved | [Automation events](/docs/v3/api-ref/events/automation-events.md) |
| `prefect.automation.action.triggered` | Automation action started | [Automation events](/docs/v3/api-ref/events/automation-events.md) |
| `prefect.automation.action.executed` | Automation action completed | [Automation events](/docs/v3/api-ref/events/automation-events.md) |
| `prefect.automation.action.failed` | Automation action failed | [Automation events](/docs/v3/api-ref/events/automation-events.md) |

### Infrastructure events

| Event | Description | Page |
| - | - | - |
| `prefect.block.{type}.loaded` | Block loaded from server | [Infrastructure events](/docs/v3/api-ref/events/infrastructure-events.md) |
| `prefect.flow-run.pull-step.executed` | Deployment pull step succeeded | [Infrastructure events](/docs/v3/api-ref/events/infrastructure-events.md) |
| `prefect.flow-run.pull-step.failed` | Deployment pull step failed | [Infrastructure events](/docs/v3/api-ref/events/infrastructure-events.md) |
| `prefect.workspace.transfer.started` | Workspace transfer started | [Infrastructure events](/docs/v3/api-ref/events/infrastructure-events.md) |
| `prefect.workspace.transfer.completed` | Workspace transfer completed | [Infrastructure events](/docs/v3/api-ref/events/infrastructure-events.md) |

### Prefect Cloud events

| Event | Description | Page |
| - | - | - |
| `prefect-cloud.automation.*` | Cloud automation lifecycle | [Automation events](/docs/v3/api-ref/events/automation-events.md) |
| `prefect-cloud.incident.*` | Incident management | [Cloud events](/docs/v3/api-ref/events/cloud-events.md) |
| `prefect-cloud.webhook.*` | Webhook reception | [Cloud events](/docs/v3/api-ref/events/cloud-events.md) |
| `prefect-cloud.{type}.{action}` | Audit log (CRUD operations) | [Cloud events](/docs/v3/api-ref/events/cloud-events.md) |

### Integration events

| Event | Description | Page |
| - | - | - |
| `prefect.docker.container.{status}` | Docker container status changes | [Infrastructure events](/docs/v3/api-ref/events/infrastructure-events.md#integration-infrastructure-events) |
| `prefect.kubernetes.pod.{phase}` | Kubernetes pod phase changes | [Infrastructure events](/docs/v3/api-ref/events/infrastructure-events.md#integration-infrastructure-events) |
| `prefect.ecs.task.{status}` | ECS task status changes | [Infrastructure events](/docs/v3/api-ref/events/infrastructure-events.md#integration-infrastructure-events) |

## Using events with automations

Events are the foundation of [automations](/docs/v3/concepts/automations.md). You can configure
[event triggers](/docs/v3/concepts/event-triggers.md) to match any event in this reference by its
name, resource labels, or related resources. See
[how to create automations](/docs/v3/how-to-guides/automations/creating-automations.md) to get started.