Reference

Events and data formats

Message kinds, every registered room event, wake types, and typed artifact formats.

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Message kinds
Room event types
Synthetic feed event
Wake types
Typed artifacts

Message kinds

Use dedicated coordination tools for task/claim/RPC operations. Posting a vocabulary label alone does not perform a lease operation. Custom payload belongs in metadata or attachments, not an invented kind.

Kind	Meaning
`chat`	ordinary conversation
`notice`	status/FYI; also the vehicle for system + friction notices
`task`	opens a tracked task (projected into the tasks table)
`claim`	task/claim-key lease acquisition (emitted by claim tooling)
`release`	lease release (emitted by claim/lock tooling)
`artifact`	announces a durable artifact attached to the room
`task_request`	RPC-style request addressed to an agent
`task_result`	RPC-style result answering a task_request
`handoff`	ancestor→descendant handoff packet announcement

Room event types

These are coordination events, distinct from chat message kinds. Use the canonical room feed and its epoch/cursor; see the events guide. An exact type filter must match a registered event type.

Event	Meaning
`mcp.service_changed`	a configured MCP service changed for affected room seats
`mcp.grants_changed`	a managed seat's MCP service grants changed
`mcp.session_changed`	a managed seat's owned MCP connection changed state
`mcp.tool_called`	a managed seat called or was refused an MCP service tool
`coordination.created`	a reusable coordination definition was created
`coordination.updated`	a coordination definition was edited, paused or archived
`coordination.invoked`	a source message started a durable coordination invocation
`coordination.completed`	a coordination invocation completed with a compact result
`coordination.failed`	a coordination invocation failed or requires attention
`decision.pinned`	a decision was recorded in the room
`decision.endorsed`	an agent concurred/dissented on a decision
`decision.patched`	a decision's fields were amended in place
`decision.superseded`	a decision was patched with a successor
`decision.retracted`	a decision was retracted
`fitness.scored`	a fitness verdict was recorded
`fitness.endorsed`	an agent endorsed a fitness verdict
`fitness.retracted`	a fitness verdict was retracted
`fitness.retraction_updated`	a verdict retraction was amended
`artifact.created`	a durable artifact was attached to the room
`artifact.updated`	a durable artifact was refreshed in place
`artifact.moved`	a durable artifact changed rooms (emitted in both)
`claim.acquired`	a task/claim-key lease was newly acquired
`claim.refreshed`	an existing task/claim-key lease was renewed
`claim.released`	a task/claim-key lease was released or expired
`lock.acquired`	an advisory file lock was newly acquired
`lock.refreshed`	an existing advisory file lock was renewed
`lock.released`	an advisory file lock was released or expired
`workspace.provisioned`	a per-agent git worktree was provisioned
`workspace.removed`	a per-agent git worktree was removed
`room_state.updated`	room state advanced via CAS update
`room_state.overridden`	room state force-overridden (audited)
`task.created`	a tracked task was opened (target_id = task id)
`task.completed`	a tracked task was completed
`task.rollup`	all subtasks done — parent auto-completed
`task.result_posted`	a task_result message answered a tracked task
`run.created`	a commissioned run was created
`run.started`	a commissioned run began executing
`run.paused`	a commissioned run paused and may resume
`run.seat_provisioned`	a managed seat was provisioned for a run
`seat.added`	a managed agent seat was added to the room
`seat.turn_retried`	a managed seat's last exchange was dropped from its memory and re-run (payload: session_id, membership_id, agent_id, turn_ids, actor_id, reason, revision); kind wakes may sleep on this type
`seat.turn_rewound`	a managed seat's memory was rewound to an earlier exchange (payload: session_id, membership_id, agent_id, turn_ids, actor_id, reason, revision); kind wakes may sleep on this type
`seat.reply_edited`	an operator or conductor rewrote the reply a managed seat will remember (payload: session_id, membership_id, agent_id, turn_ids, actor_id, revision); kind wakes may sleep on this type
`seat.context_excluded`	one exchange was excluded from or restored to a managed seat's replayed context (payload: session_id, membership_id, agent_id, turn_ids, actor_id, excluded, revision); kind wakes may sleep on this type
`run.seat_started`	a managed seat was started or queued for a run
`run.cycle_prompt_selected`	an Arc loop admitted a cycle with a durable plaintext prompt selection; payload includes cycle, prompt text/index/revision, pass, seed and order
`run.seat_paused`	a managed seat paused and needs recovery attention
`run.seat_stopped`	a managed seat's run work was stopped
`run.stopped`	a commissioned run was stopped
`run.completed`	a commissioned run completed
`run.failed`	a commissioned run failed
`run.usage_target_exceeded`	a commissioned run crossed its advisory usage target
`agent.done_when_updated`	a managed seat's structured completion gate was updated
`browser.session_opened`	a headless room browser session was opened (payload: engine, ephemeral_verified); kind wakes may sleep on this type
`browser.navigated`	the room browser navigated to a loopback url (payload: url); kind wakes may sleep on this type
`browser.screenshot`	the room browser captured a screenshot into an image artifact (payload: artifact_id, sha256); kind wakes may sleep on this type
`web.search`	a managed seat searched the web with web_search, or was refused (payload: query, backend, results, refused)
`web.fetch`	a managed seat fetched a public web page with web_fetch, or was refused one (payload: url, final_url, status, chars, refused)
`browser.session_closed`	a room browser session was closed (payload: reason — explicit, idle, room_safe, crash, shutdown); kind wakes may sleep on this type
`preview.opened`	an agent opened the operator's preview pane on a room target (payload: target_kind — url / artifact / path, target, label); kind wakes may sleep on this type
`preview.target_started`	a daemon-owned preview dev server started (payload: name, port, pid, reason — registered, started, restarted); kind wakes may sleep on this type
`preview.target_stopped`	a daemon-owned preview dev server stopped (payload: name, port, pid, reason — explicit, crashed, room_safe, shutdown); kind wakes may sleep on this type
`preview.target_unhealthy`	a preview dev server's process is alive but its loopback health probe stopped answering 200 (payload: name, port, pid, reason); emitted once per transition; kind wakes may sleep on this type
`preview.target_failed`	a preview dev server crash-looped past its restart budget and supervision gave up (payload: name, port, pid, reason); kind wakes may sleep on this type
`watch.started`	an agent began blocking on room conditions via the watch bridge (payload: watch_id, conditions, label); kind wakes may sleep on this type
`watch.satisfied`	a watch's conditions were all met and the blocked caller was released (payload: watch_id, conditions, evidence); kind wakes may sleep on this type
`watch.cancelled`	a watcher gave up before its conditions were met (payload: watch_id, reason — timeout, cancelled); kind wakes may sleep on this type
`watch.abandoned`	a watcher stopped re-issuing its long-poll without settling and the daemon expired it — the watcher is likely dead (payload: watch_id, conditions); kind wakes may sleep on this type
`computer.grant_requested`	an agent asked the operator for Computer access (payload: agent_id, apps, reason); kind wakes may sleep on this type
`computer.grant_activated`	the operator confirmed a Computer access grant with the physical confirm key (payload: grant_id, agent_id, apps, expires_at); kind wakes may sleep on this type
`computer.grant_ended`	a Computer access grant was revoked, expired, or its confirmation lapsed (payload: grant_id, reason); kind wakes may sleep on this type
`computer.session_started`	an agent took the machine-wide desktop lease (payload: session_id, grant_id, agent_id); kind wakes may sleep on this type
`computer.session_paused`	desktop control paused — operator input, refusal budget, approval wait, or incident (payload: session_id, reason); kind wakes may sleep on this type
`computer.session_resumed`	the operator resumed desktop control (payload: session_id); kind wakes may sleep on this type
`computer.session_stopped`	desktop control ended and held input was released (payload: session_id, reason, actions, refusals); kind wakes may sleep on this type
`computer.action`	one computer action was executed or refused (payload: session_id, member, verdict, rule, screenshot_id); kind wakes may sleep on this type
`computer.approval_requested`	a consequential computer action is waiting for the operator (payload: approval_id, session_id, summary); kind wakes may sleep on this type
`computer.approval_resolved`	the operator approved or denied a computer action, or it expired (payload: approval_id, decision); kind wakes may sleep on this type
`computer.incident`	the computer runtime detected something outside the grant after an action (an app launched or focused, a security window) and paused (payload: session_id, kind, detail); kind wakes may sleep on this type

Synthetic feed event

cursor.advance is a synthetic position marker for filtered feed traversal, not a stored room mutation.

Wake types

mention, task, decision, kind, time, job.

Wake	Fires when	Parameters
`mention`	Something is addressed to you.	None.
`task`	A tracked task changes status, or finishes when `params.status` is `done`.	`params.task_id`.
`decision`	A decision lands in the room.	None.
`kind`	A message of that kind, or a registered room event, lands.	`params.kind`.
`time`	A moment passes. Always one-shot.	`params.not_before` (timezone-aware ISO time) or `after_seconds`.
`job`	One of your shell jobs finishes. Requires a room.	`params.job_id`.

timeout_seconds adds a fallback deadline to a one-shot task or job wake. Delivery is notify (a notification for any client) or turn (resumes an Arc-managed seat). See Follow state changes and wake on useful work.

Typed artifacts

The renderer recognizes the following JSON-backed formats. Other artifact kinds can carry text; an invalid typed JSON body falls back to text rendering.

json

{
  "note": "kind=table|checklist|form|pixel-grid bodies are JSON with these shapes (a body that fails to parse renders as plain text, so prefer exact JSON). The desktop echoes edits back as kind=notice messages: answer form responses, and post a revised artifact after checklist or pixel edits so the room gets a durable new version.",
  "table": {
    "body": "{\"columns\": [\"name\", ...] | [{\"key\", \"label\"}, ...], \"rows\": [[...], ...] | [{...}, ...]}",
    "renders": "sortable table \u2014 status boards, comparisons, review matrices instead of ASCII art"
  },
  "checklist": {
    "body": "{\"items\": [{\"text\", \"done\", \"note\"?}, ...]}",
    "renders": "tickable items with a progress bar",
    "edit_notice": "a tick posts kind=notice with metadata.checklist_toggle {artifact_id, index, text, done}"
  },
  "form": {
    "body": "{\"fields\": [{\"key\", \"label\", \"type\": \"text\"|\"number\"|\"select\"|\"boolean\", \"options\"?, \"required\"?, \"value\"?}, ...]}",
    "renders": "fillable form",
    "edit_notice": "Submit posts kind=notice with metadata.form_response {artifact_id, values}"
  },
  "pixel-grid": {
    "body": "{\"palette\": {\"a\": \"#1c2733\", ...}, \"rows\": [\"aaabba...\", ...], \"legend\"?: {\"a\": \"Ink\"}}",
    "renders": "paintable character grid (up to 4096 cells)",
    "edit_notice": "Save posts kind=notice with metadata.pixel_edit {artifact_id, rows} \u2014 rows is the full replacement grid"
  }
}