Messaging

Steer appends a user message to a session. Message envelopes are channel-agnostic, so API input and channel input use the same shape. Outbound delivery has its own page: Webhooks.

Steer (inbound)

Send a message to a running or idle session; it wakes and continues with its prior context. Minimal form is just text:

import { connectSession } from "@opencomputer/sdk";

const live = await connectSession({ sessionId, clientToken });
await live.steer("also check the CI config", { idempotencyKey: "msg_01" });

POST https://api.opencomputer.dev/v3/sessions/ses_.../messages
Authorization: Bearer $CLIENT_TOKEN
Content-Type: application/json

{
  "text": "also check the CI config",
  "idempotency_key": "msg_01"
}

Pass idempotency_key so retries (flaky network, double-click) are de-duplicated — applied at most once per session, so the same key is safe to reuse across different sessions.

Message input

Steer with { text, idempotency_key? }, or a fuller envelope when you need a source or a threading anchor:

{
  "envelope": {
    "id": "client:abc123",
    "source": "client",
    "conversation": { "source": "client", "ref": "thread-42" },
    "text": "also check the CI config",
    "refs": {},
    "raw": {}
  }
}

These fields don’t all land in one place — the appended event splits them:

You send	Lands on the event as
`text`	`body.text` — the content the agent reads
`raw`	`body.raw` — untouched original payload (optional; never interpreted)
`id` (or top-level `idempotency_key`)	the idempotency key, deduped per session
`source`, `conversation`, `refs`	merged into the event’s top-level `refs` — opaque routing/threading anchors
(the sender)	the event’s `actor` — `human` \| `agent` \| `system`, namespaced

So a *.message event’s body is just { text, raw? } — source/conversation/refs live under the event’s top-level refs, and the sender under actor (not inside body). Outbound agent.message bodies are likewise { text }. To deliver a session’s output, register a webhook destination. Deliveries carry the full Event; see Webhooks. The same envelope also underpins Channels in Labs.

Authentication Webhooks

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Steer (inbound)

Message input

​Steer (inbound)

​Message input

Steer (inbound)

Message input