Events

Every state change in the kernel produces an immutable event. The event log is the system of record. Executions, steps, and approvals are projections of it.

Event structure

{
  "execution_id": "0192f3a4-...",
  "event_seq": 7,
  "type": "step.succeeded",
  "payload": {
    "step_id": "…",
    "step_type": "llm_call",
    "target": "gpt-5.5",
    "usage": { "input_tokens": 812, "output_tokens": 96 }
  },
  "occurred_at": "2026-07-07T12:00:00Z"
}

event_seq is monotonic per execution. It gives total order within one execution, not across executions.
Events are append-only. Paging is by after_seq.
Every step.* payload carries step_id and step_type (tool_call, llm_call, or local), so any event is self-describing in isolation.

Execution events

The execution.* types cover the lifecycle of the run itself. Payloads carry execution_id and status, plus session and deadline_at when the execution has them. execution.started also carries parent_execution_id when the execution continues an earlier one in its session.

Type	When
`execution.created`	Client created the execution. Payload carries `created_by`, `on_behalf_of` when set, and `spawned_by` for a subagent.
`execution.forked`	Fork created. Payload carries `source_execution_id`, `fork_seq`, `policy_override`, and resource `restoration` when present.
`execution.started`	The execution began running and its first dispatch is queued.
`execution.blocked`	Paused on a human approval, or suspended with `reason` `awaiting_steps`.
`execution.resumed`	No step is waiting anymore, and work continues.
`execution.completed`	Terminal, success. Payload carries the `output`.
`execution.failed`	Terminal, failure. Payload carries a `reason`.
`execution.cancelled`	Terminal. The payload’s `reason` is `client_cancelled`, `deadline_exceeded`, or `parent_agent_terminal`.

Step events

The step.* types cover the lifecycle of each effect, whether a tool call, an LLM call, or a local step.

Type	When
`step.proposed`	The agent submitted the step and the kernel has not decided yet.
`step.allowed`	Policy allowed it. Payload carries the matched `rule_id`.
`step.denied`	Policy denied it, or an approval was denied or expired.
`step.awaiting_approval`	Policy requires a human decision, and an approval was created.
`step.rate_limited`	A rule’s rate limit refused or parked it. No step row is written.
`step.executing`	Written before the external call runs. Resource changes carry `resources` keys and their `generations`, including on retries.
`step.succeeded`	Terminal. An `llm_call` also carries `usage` when token counts were found in the response.
`step.failed`	Terminal, with the recorded `error`.
`step.cancelled`	Terminal. The execution was cancelled while the step was in flight, so whether the effect ran is unknown.

Payloads stay lean. They identify the step (step_id, step_type, and target where it is known) and carry decision context (rule_id, error, and the policy_hash of the bundle that decided, a SHA-256 of its YAML). Results are not in the payload. The result of a tool call, and the request and response bodies of an llm_call, live on the step itself, so fetch them with GET /v0/executions/{id}/steps/{step_id}.

Resource events

Resource payloads carry key.

Type	When
`resource.registered`	Resource registered or checkpointing enabled, with `driver_id`, `configuration`, `coverage_reuse`, `every_steps`, and `on_completion`.
`resource.initialized`	Fork initialization with `generation` and optional `checkpoint_ref`; no reference means initial state.
`resource.bound`	Physical resource assigned, with its `binding`.
`resource.checkpointed`	Capture accepted, with `generation`, `checkpoint_ref`, and coverage start `covered_seq`.
`resource.checkpoint_failed`	Capture failed or refused, with `generation` and `error`.

Approval events

The approval.* types cover the lifecycle of each human-in-the-loop approval. Payloads carry approval_id, step_id, execution_id, and status.

Type	When
`approval.requested`	An approval was created.
`approval.granted`	A human granted it, with `decided_by`, `rationale`, and `asserted_by` when a delegate named the approver.
`approval.denied`	A human denied it.
`approval.expired`	The approval’s timeout elapsed. The gated step is denied and the execution resumes.

Dispatch events

The dispatch.* types cover webhook delivery. Payloads carry dispatch_id, execution_id, status, and attempt, which counts the times the kernel has claimed this dispatch and handed the execution to an agent. It is 0 until the first claim.

Type	When
`dispatch.queued`	A dispatch was created and enqueued.
`dispatch.acked`	A delivery attempt returned `200 OK`.
`dispatch.failed`	A delivery attempt failed. Emitted on every attempt, including the one that reaches `max_attempts`.
`dispatch.discarded`	A claimed dispatch was dropped undelivered; its execution was already terminal.

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Concepts

Integrations

Operations

Event structure

Execution events

Step events

Resource events

Approval events

Dispatch events

​Event structure

​Execution events

​Step events

​Resource events

​Approval events

​Dispatch events

Event structure

Execution events

Step events

Resource events

Approval events

Dispatch events