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Event subscriptions

Event subscriptions allow you to receive messages when events occur across your Cloudflare account. Cloudflare products (e.g., KV, Workers AI, Workers) can publish structured events to a queue, which you can then consume with Workers or HTTP pull consumers to build custom workflows, integrations, or logic.

For more information on Event Subscriptions, refer to the management guide.

Available Workflows events

`instance.queued`

Triggered when an instance was created and is awaiting execution.

Example:

{
  "type": "cf.workflows.workflow.instance.queued",
  "source": {
    "type": "workflows.workflow",
    "workflowName": "my-workflow"
  },
  "payload": {
    "versionId": "v1",
    "instanceId": "inst-12345678-90ab-cdef-1234-567890abcdef"
  },
  "metadata": {
    "accountId": "f9f79265f388666de8122cfb508d7776",
    "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f",
    "eventSchemaVersion": 1,
    "eventTimestamp": "2025-05-01T02:48:57.132Z"
  }
}

`instance.started`

Triggered when an instance starts or resumes execution.

Example:

{
  "type": "cf.workflows.workflow.instance.started",
  "source": {
    "type": "workflows.workflow",
    "workflowName": "my-workflow"
  },
  "payload": {
    "versionId": "v1",
    "instanceId": "inst-12345678-90ab-cdef-1234-567890abcdef"
  },
  "metadata": {
    "accountId": "f9f79265f388666de8122cfb508d7776",
    "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f",
    "eventSchemaVersion": 1,
    "eventTimestamp": "2025-05-01T02:48:57.132Z"
  }
}

`instance.paused`

Triggered when an instance pauses execution.

Example:

{
  "type": "cf.workflows.workflow.instance.paused",
  "source": {
    "type": "workflows.workflow",
    "workflowName": "my-workflow"
  },
  "payload": {
    "versionId": "v1",
    "instanceId": "inst-12345678-90ab-cdef-1234-567890abcdef"
  },
  "metadata": {
    "accountId": "f9f79265f388666de8122cfb508d7776",
    "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f",
    "eventSchemaVersion": 1,
    "eventTimestamp": "2025-05-01T02:48:57.132Z"
  }
}

`instance.errored`

Triggered when an instance step throws an error.

Example:

{
  "type": "cf.workflows.workflow.instance.errored",
  "source": {
    "type": "workflows.workflow",
    "workflowName": "my-workflow"
  },
  "payload": {
    "versionId": "v1",
    "instanceId": "inst-12345678-90ab-cdef-1234-567890abcdef"
  },
  "metadata": {
    "accountId": "f9f79265f388666de8122cfb508d7776",
    "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f",
    "eventSchemaVersion": 1,
    "eventTimestamp": "2025-05-01T02:48:57.132Z"
  }
}

`instance.terminated`

Triggered when an instance is manually terminated.

Example:

{
  "type": "cf.workflows.workflow.instance.terminated",
  "source": {
    "type": "workflows.workflow",
    "workflowName": "my-workflow"
  },
  "payload": {
    "versionId": "v1",
    "instanceId": "inst-12345678-90ab-cdef-1234-567890abcdef"
  },
  "metadata": {
    "accountId": "f9f79265f388666de8122cfb508d7776",
    "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f",
    "eventSchemaVersion": 1,
    "eventTimestamp": "2025-05-01T02:48:57.132Z"
  }
}

`instance.completed`

Triggered when an instance finishes execution successfully.

Example:

{
  "type": "cf.workflows.workflow.instance.completed",
  "source": {
    "type": "workflows.workflow",
    "workflowName": "my-workflow"
  },
  "payload": {
    "versionId": "v1",
    "instanceId": "inst-12345678-90ab-cdef-1234-567890abcdef"
  },
  "metadata": {
    "accountId": "f9f79265f388666de8122cfb508d7776",
    "eventSubscriptionId": "1830c4bb612e43c3af7f4cada31fbf3f",
    "eventSchemaVersion": 1,
    "eventTimestamp": "2025-05-01T02:48:57.132Z"
  }
}