---
summary: "Outbound message lifecycle API for channel plugins: adapters, receipts, durable sends, live preview, and reply pipeline helpers"
title: "Channel outbound API"
read_when:
  - You are building or refactoring a messaging channel plugin send path
  - You need durable final reply delivery, receipts, live preview finalization, or receive acknowledgement policy
  - You are migrating from channel-message or legacy reply dispatch helpers
---

Channel plugins expose outbound message behavior from
`openclaw/plugin-sdk/channel-outbound`. Use
`openclaw/plugin-sdk/channel-inbound` for receive/context/dispatch
orchestration.

Core owns queueing, durability, the durable **ingress monitor and drain**
(`createChannelIngressMonitor`, `createChannelIngressDrain`, and
`openChannelIngressDrain`), generic retry policy, turn-adoption lifecycle
(`turnAdoptionLifecycle` / `bindIngressLifecycleToReplyOptions`), hooks,
receipts, and the shared `message` tool. The plugin owns native
send/edit/delete calls, target normalization, platform threading, selected
quotes, notification flags, account state, ingress inspection and payload
encoding, lane keys, non-retryable predicates, optional supersede
authorization, and platform-specific side effects.

## Durable ingress monitors

Use `createChannelIngressMonitor(...)` when a channel must persist accepted
transport events before dispatch. It composes a channel ingress queue and drain
with the shared admission, polling, pruning, delivery, and shutdown lifecycle.
Use the lower-level `createChannelIngressDrain(...)` only when the transport
owns a materially different admission or pump contract.

The required options are:

| Option                           | Contract                                                                                                                                                                                                                                                                                                         |
| -------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `queue`                          | A `ChannelIngressQueue`, or a lazy factory that opens the account-scoped queue.                                                                                                                                                                                                                                  |
| `inspect(raw, context)`          | Returns the stable `eventId` and serialized `laneKey`, or `null` for an ignored event. Claim-time facts must match the persisted id and lane.                                                                                                                                                                    |
| `payload`                        | Supplies the payload version plus body serialization/deserialization. Use `storage: "raw-event"` for the standard `{ version, rawEvent }` string envelope, or provide custom encode/decode callbacks for an existing channel-specific shape. `createClaimError` classifies invalid versions or changed identity. |
| `deliver(raw, lifecycle, claim)` | Dispatches one decoded event and receives the complete adoption lifecycle. It may return `completed`, `deferred`, `failed-retryable`, or nothing.                                                                                                                                                                |
| `pollIntervalMs`                 | Schedules recovery/drain polls while the monitor is running.                                                                                                                                                                                                                                                     |
| `retention`                      | Supplies the prune cadence and completed/failed TTL and entry caps.                                                                                                                                                                                                                                              |

The monitor serializes admissions so append backoff cannot invert a lane. The
default bounded append delays are `0`, `100`, and `300` ms; exhaustion rejects
the transport callback instead of dispatching an event that was not made
durable. At claim time it decodes the versioned payload, re-runs `inspect`, and
rejects an id or lane mismatch before delivery.

`onDurableAdmission(raw, context)` runs after every durable enqueue, including
duplicates. `context.isNew` is `true` if and only if this admission inserted the
`(queue_name, event_id)` row. It does not indicate claim ownership or eventual
delivery. If retention previously pruned the row, a later admission may insert
it again and report `isNew: true`.

`deliver` receives `onAdopted`, `onDeferred`, `onAdoptionFinalizing`, `onFailed`,
`onCancelled`, `onAbandoned`, and `abortSignal`. Use `onFailed` for delivery
errors, `onCancelled` for explicit pre-adoption cancellation that must preserve
retry accounting, and `onAbandoned` when a non-adopted turn should consume a
retry attempt. Returning without an explicit handoff marks a terminal
no-dispatch event adopted. `admission` is always `exclusive`. A deferred handoff
keeps the claim held, while shutdown or abort leaves unadopted work retryable.
The monitor tracks delivery independently from claim settlement because
adoption can tombstone a row before the channel's delivery promise returns.

Optional settings include custom append delays, a `drain` option block for
advanced drain ordering/concurrency/retry policy, an external `abortSignal`, a
clock, pump error reporting, a stopped-error factory, and admission policy.
The returned monitor exposes `admit`, `ensureQueueAvailable`, `start`, `pause`,
`stop`, `waitForIdle`, `isRunning`, and `isStopped`. Use the idempotent
`ensureQueueAvailable()` check when plugin-owned migration or preparation must
run after the queue opens but before the drain starts. `stop` first settles
accepted admissions, then aborts and disposes the drain, waits for the pump and
active deliveries, and disposes again to close the lazy-creation race.

Keep transport-specific redaction, raw-envelope validation, non-retryable
classification, and persisted payload shape in the plugin. Webhook transports
should acknowledge only after `admit` resolves; non-replay transports should
surface durable append exhaustion rather than silently dispatching.

## Adapter

Most plugins define one `message` adapter:

```ts
import {
  defineChannelMessageAdapter,
  createMessageReceiptFromOutboundResults,
} from "openclaw/plugin-sdk/channel-outbound";

export const demoMessageAdapter = defineChannelMessageAdapter({
  id: "demo",
  durableFinal: {
    capabilities: {
      text: true,
      replyTo: true,
      thread: true,
      messageSendingHooks: true,
    },
  },
  send: {
    text: async ({ cfg, to, text, accountId, replyToId, threadId, signal }) => {
      const sent = await sendDemoMessage({
        cfg,
        to,
        text,
        accountId: accountId ?? undefined,
        replyToId: replyToId ?? undefined,
        threadId: threadId == null ? undefined : String(threadId),
        signal,
      });

      return {
        receipt: createMessageReceiptFromOutboundResults({
          results: [{ channel: "demo", messageId: sent.id, conversationId: to }],
          kind: "text",
          threadId: threadId == null ? undefined : String(threadId),
          replyToId: replyToId ?? undefined,
        }),
      };
    },
  },
});
```

Only declare capabilities the native transport actually preserves. Cover
each declared send, receipt, live-preview, and receive-ack capability with
the contract helpers exported from this subpath.

## Outbound echo suppression

When a platform may redeliver the plugin's own outbound message as inbound, call `recordOutboundMessageIdentity(...)` with the channel, account, conversation, and a stable platform message or source identity. The shared inbound turn path drops matching identities for a bounded 30-second window before session recording or agent dispatch; a source identity may be reserved before send or refreshed when a channel route is removed to close delivery races. `isRecentOutboundMessageIdentity(...)` exposes the same query for channel diagnostics and tests. Do not maintain a parallel channel-local TTL cache for the same stable identity.

## Plain-text sanitization

Use `sanitizeForPlainText(...)` when an outbound adapter needs to convert the
supported HTML formatting tags into lightweight text markup. The default keeps
the existing chat-style bold and strikethrough markers. Pass
`{ style: "markdown" }` only when the channel reparses the result as Markdown:

```ts
import { sanitizeForPlainText } from "openclaw/plugin-sdk/channel-outbound";

const chatText = sanitizeForPlainText(text);
const markdownText = sanitizeForPlainText(text, { style: "markdown" });
```

The Markdown style uses `**bold**` and `~~strikethrough~~`; italic and inline
code keep `_italic_` and backtick markers in both styles. Select the style at
the channel boundary instead of rewriting marker text after sanitization.

## Delivery Evidence

A `MessageReceipt` records the result returned by a channel adapter. Concrete
platform message identifiers show that the platform send path accepted the
message; they do not prove that a recipient's device displayed or read it.
Destination and routing identifiers such as chat, channel, room, conversation,
or recipient JID are metadata, never `platformMessageIds`. Receipts without
platform message identifiers are local receipt metadata only. A
provider-observed receipt thread overrides the requested route thread. If a
batch contains conflicting provider threads, each part retains its thread and
the aggregate receipt omits `threadId`. Channels with read receipts or
device-delivery state should track those facts through a separate
channel-specific path.

When an adapter intentionally omits a send before dispatch, return
`outcome: "not_sent"` with an empty receipt and no message ID (legacy outbound
adapters use an empty `messageId`). Core records `adapter_returned_no_send` as
an intentional suppression, counts no physical send, and skips send-success
and commit hooks. Do not use this outcome for an acknowledged send without a
platform ID or for an unknown result after dispatch. An empty receipt alone
does not distinguish those states; existing acknowledgement behavior is
unchanged when `outcome` is omitted.

If a channel adapter can prove that retrying a failure cannot duplicate a
recipient-visible send and no finalization-capable call began, throw
`new PlatformMessageNotDispatchedError("...", { cause: error })` from
`openclaw/plugin-sdk/error-runtime`. Core can then clear stale send-attempt
evidence and safely retry the queued intent. Only the adapter that owns the
final dispatch boundary may make this assertion. Never use the marker after a
finalization/send call begins or returns an ambiguous result; false marking can
duplicate messages.

## Existing outbound adapters

If the channel already has a compatible `outbound` adapter, derive the
message adapter instead of duplicating send code:

```ts
import { createChannelMessageAdapterFromOutbound } from "openclaw/plugin-sdk/channel-outbound";

export const messageAdapter = createChannelMessageAdapterFromOutbound({
  id: "demo",
  outbound,
  durableFinal: {
    capabilities: {
      text: true,
      media: true,
    },
  },
});
```

## Durable sends

Runtime send helpers also live on `channel-outbound`:

- `sendDurableMessageBatch(...)`
- `withDurableMessageSendContext(...)`
- `deliverInboundReplyWithMessageSendContext(...)`
- draft streaming/progress helpers such as `resolveChannelDraftStreamingChunking(...)`

`sendDurableMessageBatch(...)` returns one explicit outcome:

| Outcome          | Meaning                                                                                 |
| ---------------- | --------------------------------------------------------------------------------------- |
| `sent`           | at least one visible platform message was accepted by the platform send path            |
| `suppressed`     | no platform message should be treated as missing                                        |
| `partial_failed` | at least one platform message was accepted before a later payload or side effect failed |
| `failed`         | no platform receipt was produced                                                        |

Use `payloadOutcomes` when a batch mixes sent, suppressed, and failed
payloads. Do not infer hook cancellation from an empty legacy
direct-delivery result.

When a transport creates a thread during its first successful send, the
outbound adapter may implement `adoptTargetFromDelivery(...)`. Return the
typed thread ID from the platform receipt and core carries it into later
payloads, pins, and post-delivery hooks in that durable batch. Core never
replaces an explicit caller thread, and it does not infer adoption from
`receipt.threadId` without the adapter opt-in.

### Automatic unknown-send reconciliation

Set `message.durableFinal.automaticUnknownSendReconciliation` only when the
plugin can reconcile an ambiguous provider send from persisted, post-policy
state without rerunning modifying hooks or regenerating provider payloads.
Core considers this opt-in after hooks and cancellation, and only for exactly
one accepted prepared payload. Multi-payload batches do not opt in
automatically.

The adapter must also advertise `capabilities.reconcileUnknownSend: true` and
provide `reconcileUnknownSend(...)`. Use `reconcileUnknownSendKinds` to name
the concrete transport branches the plugin can prove, such as `text` or
`media`. If the kind map is present, the selected branch must be `true`.
Omitting the map means the callback claims every selected branch, so prefer an
explicit map for new plugins.

The callback must use provider-owned idempotency or authoritative readback to
return `sent` with the actual provider receipt, `not_sent` only when a fresh
send is provably safe, or `unresolved` when neither outcome can be proven.
When reconciliation is explicitly required, unsupported prepared shapes fail
before provider I/O. During recovery, missing, incomplete, or mismatched
provider proof must fail closed rather than replaying content that could
already be visible.

If reconciliation needs provider-owned persisted evidence, implement
`afterUnknownSendTerminal(...)`. Core calls it after the ambiguous queue row
has authoritatively moved to failed, including retry-budget exhaustion. Use it
to remove provider-owned plans or payloads that are no longer needed. Cleanup
is best effort and must be idempotent; a failure is logged without making the
terminal queue row replayable again.

## Deferred delivery admission

Use `message.durableFinal.admitDeferredDelivery(...)` when a resolved account
cannot safely accept core-managed outbound or deferred delivery. Core calls
this hook synchronously before live outbound work, including paths that skip
queue persistence, and again before replaying a recovered intent. The context
includes `cfg`, `channel`, `to`, `accountId`, and a `phase` of `live` or
`recovery`.

Return `{ status: "allowed" }` to continue. Return
`{ status: "permanent_rejection", reason }` when the delivery must not be
persisted, sent directly, or replayed. A live rejection fails before queue
creation, message hooks, or platform work. A recovery rejection marks the
queued record failed and skips reconciliation and replay. Omitting the hook
means allowed.

The hook is a synchronous admission decision, not a send path. Read only
already-loaded config or runtime state; do not perform network, filesystem, or
other asynchronous I/O. Contract tests should exercise both phases and both
result variants through `ChannelMessageDurableFinalAdapter` from
`openclaw/plugin-sdk/channel-outbound`.

## Compatibility dispatch

Assemble inbound reply dispatch through `dispatchChannelInboundReply(...)`
from `channel-inbound`. Keep platform delivery in the delivery adapter; use
`channel-outbound` for message adapters, durable sends, receipts, live
preview, and reply pipeline options.
