--- summary: "Plugin hooks: intercept agent, tool, message, session, and Gateway lifecycle events" title: "Plugin hooks" read_when: - You are building a plugin that needs before_tool_call, before_agent_reply, message hooks, or lifecycle hooks - You need to block, rewrite, or require approval for tool calls from a plugin - You are deciding between internal hooks and plugin hooks - You are projecting OpenClaw cron wakes into an external host scheduler --- Plugin hooks are in-process extension points for OpenClaw plugins: inspect or change agent runs, tool calls, message flow, session lifecycle, subagent routing, installs, or Gateway startup. Use [internal hooks](/automation/hooks) instead for a small operator-installed `HOOK.md` script reacting to command and Gateway events such as `/new`, `/reset`, `/stop`, `agent:bootstrap`, or `gateway:startup`. ## Quick start Register typed hooks with `api.on(...)` from the plugin entry: ```typescript import { definePluginEntry } from "openclaw/plugin-sdk/plugin-entry"; export default definePluginEntry({ id: "tool-preflight", name: "Tool Preflight", register(api) { api.on( "before_tool_call", async (event) => { if (event.toolName !== "web_search") { return; } return { requireApproval: { title: "Run web search", description: `Allow search query: ${String(event.params.query ?? "")}`, severity: "info", timeoutMs: 60_000, }, }; }, { priority: 50 }, ); }, }); ``` Handlers that can return decisions or modifications run sequentially in descending `priority`; same-priority handlers keep registration order. Observation-only handlers run in parallel, and fire-and-forget observation dispatches can overlap with later events. Do not use priority to order observation side effects. `api.on(name, handler, opts?)` accepts: | Option | Effect | | ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `priority` | Ordering; higher runs first. | | `timeoutMs` | Per-hook await budget. When it expires, OpenClaw stops awaiting that handler and moves on. It does not cancel the handler or its side effects. Omit to use the runner's default per-hook timeout. | Operators can set hook budgets without patching plugin code: ```json { "plugins": { "entries": { "my-plugin": { "hooks": { "timeoutMs": 30000, "timeouts": { "before_prompt_build": 90000, "agent_end": 60000 } } } } } } ``` `hooks.timeouts.` overrides `hooks.timeoutMs`, which overrides the plugin-authored `api.on(..., { timeoutMs })` value. Each value must be a positive integer up to 600000 ms. Prefer per-hook overrides for known-slow hooks so one plugin does not get a longer budget everywhere. A timed-out handler promise continues running because hook callbacks do not receive a cancellation signal. The hook dispatch can release its Gateway admission while that plugin work is still in progress. Plugins that own long-running work must provide their own cancellation and shutdown lifecycle. Outbound modifying hooks `message_sending` and `reply_payload_sending` use a 15-second default per handler. If one times out, OpenClaw logs the plugin error and continues with the latest payload so the serialized delivery lane can settle. Set a larger per-hook budget for plugins that intentionally do slower work before delivery. Channel plugins that use `createReplyDispatcher` can likewise declare a larger positive per-stage budget with `beforeDeliverOptions: { timeoutMs }`, or when appending work with `dispatcher.appendBeforeDeliver(handler, { timeoutMs })`. Without an owner-declared budget, those callbacks use the same 15-second default so a hung callback cannot retain the serialized delivery lane. Each hook receives `event.context.pluginConfig`, the resolved config for the plugin that registered that handler. OpenClaw injects it per handler without mutating the shared event object other plugins see. ## Hook catalog Hooks are grouped by the surface they extend. **Bold** names accept a decision result (block, cancel, override, or require approval); the rest are observation-only. **Agent turn** | Hook | Purpose | | ------------------------------- | ---------------------------------------------------------------------------------------- | | `before_model_resolve` | Override provider or model before session messages load | | `agent_turn_prepare` | Consume queued plugin turn injections and add same-turn context before prompt hooks | | `before_prompt_build` | Add dynamic context or system-prompt text before the model call | | `before_agent_start` | Compatibility-only combined phase; prefer the two hooks above | | **`before_agent_run`** | Inspect the final prompt and session messages before model submission; can block the run | | **`before_agent_reply`** | Short-circuit the model turn with a synthetic reply or silence | | **`before_agent_finalize`** | Inspect the natural final answer and request one more model pass | | `agent_end` | Observe final messages, success state, and run duration | | `heartbeat_prompt_contribution` | Add heartbeat-only context for background monitor and lifecycle plugins | **Conversation observation** | Hook | Purpose | | ----------------------------------------- | ------------------------------------------------------------------------------------------------------------------ | | `model_call_started` / `model_call_ended` | Sanitized provider/model call metadata: timing, outcome, bounded request-id hashes. No prompt or response content. | | `llm_input` | Provider input: system prompt, prompt, history | | `llm_output` | Provider output, usage, and the resolved `contextTokenBudget` when available | **Tools** | Hook | Purpose | | -------------------------- | --------------------------------------------------------- | | **`before_tool_call`** | Rewrite tool params, block execution, or require approval | | `after_tool_call` | Observe tool results, errors, and duration | | `resolve_exec_env` | Contribute plugin-owned environment variables to `exec` | | **`tool_result_persist`** | Rewrite the assistant message produced from a tool result | | **`before_message_write`** | Inspect or block an in-progress message write (rare) | **Messages and delivery** | Hook | Purpose | | ------------------------------- | ----------------------------------------------------------------- | | **`inbound_claim`** | Claim an inbound message before agent routing (synthetic replies) | | **`channel_pairing_requested`** | Observe newly created DM pairing requests | | `message_received` | Observe inbound content, sender, thread, and metadata | | **`message_sending`** | Rewrite outbound content or cancel delivery | | **`reply_payload_sending`** | Mutate or cancel normalized reply payloads before delivery | | `message_sent` | Observe outbound delivery success or failure | | **`before_dispatch`** | Inspect or rewrite an outbound dispatch before channel handoff | | **`reply_dispatch`** | Participate in the final reply-dispatch pipeline | **Sessions and compaction** | Hook | Purpose | | ---------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `session_start` / `session_end` | Track session lifecycle boundaries. `reason` is one of `new`, `reset`, `idle`, `daily`, `compaction`, `deleted`, `shutdown`, `restart`, or `unknown`. `shutdown`/`restart` fire from the Gateway shutdown finalizer when the process stops or restarts with active sessions, so plugins (memory, transcript stores) can finalize ghost rows instead of leaving them open across restarts. The finalizer is bounded so a slow plugin cannot block SIGTERM/SIGINT. | | `before_compaction` / `after_compaction` | Observe or annotate compaction cycles | | `before_reset` | Observe session-reset events (`/reset`, programmatic resets) | **Subagents** - `subagent_spawned` / `subagent_ended` - observe subagent launch and completion. - `subagent_delivery_target` - compatibility hook for completion delivery when no core session binding can project a route. - `subagent_spawning` - deprecated compatibility hook. Core now prepares `thread: true` subagent bindings through channel session-binding adapters before `subagent_spawned` fires. - `subagent_spawned` includes `resolvedModel` and `resolvedProvider` when OpenClaw has resolved the child session's native model before launch. - `subagent_ended` carries `targetSessionKey` (identity - matches `subagent_spawned.childSessionKey`), `targetKind` (`"subagent"` or `"acp"`), `reason`, optional `outcome` (`"ok"`, `"error"`, `"timeout"`, `"killed"`, `"reset"`, or `"deleted"`), optional `error`, `runId`, `endedAt`, `accountId`, and `sendFarewell`. It does **not** include `agentId` or `childSessionKey`; use `targetSessionKey` to correlate with the matching `subagent_spawned` event. **Lifecycle** | Hook | Purpose | | -------------------------------- | ---------------------------------------------------------------------------------------------------- | | `gateway_start` / `gateway_stop` | Start or stop plugin-owned services with the Gateway | | `deactivate` | Deprecated compatibility alias for `gateway_stop`; use `gateway_stop` in new plugins | | `cron_reconciled` | Reconcile against the complete Gateway cron state after startup or reload | | `cron_changed` | Observe Gateway-owned cron lifecycle changes (added, updated, removed, started, finished, scheduled) | | **`before_install`** | Inspect staged skill or plugin install material from a loaded plugin runtime | ### Channel pairing requests Use `channel_pairing_requested` when a plugin needs to notify an operator or write an audit record after an unpaired DM sender creates a pending pairing request. The hook is dispatched when the request is created; channel delivery of the pairing reply is not delayed by slow or failing hook handlers. ```typescript api.on("channel_pairing_requested", async (event) => { await notifyOperator({ text: `New ${event.channel} pairing request from ${event.senderId}: ${event.code}`, }); }); ``` The hook is observation-only. It does not approve, reject, suppress, or rewrite the pairing reply. The payload includes the channel, optional `accountId`, channel-scoped `senderId`, pairing `code`, and channel metadata. Treat the pairing code as a live single-use approval credential and deliver it only to a trusted operator sink. Treat `metadata` as untrusted sender-supplied identity text. The hook does not include the inbound message body or media. ## Debug runtime hooks Use `before_model_resolve` to switch provider or model for an agent turn - it runs before model resolution. `llm_output` only runs after a model attempt produces assistant output. For proof of the effective session model, inspect runtime registrations, then use `openclaw sessions` or the Gateway session/status surfaces. To debug provider payloads, start the Gateway with `--raw-stream` and `--raw-stream-path ` to write raw model stream events to a jsonl file. ## Tool call policy `before_tool_call` receives: - `event.toolName` - `event.params` - optional `event.toolKind` and `event.toolInputKind`, host-authoritative discriminators for tools that intentionally share names; for example, outer code-mode `exec` calls use `toolKind: "code_mode_exec"` and include `toolInputKind: "javascript" | "typescript"` when the input language is known - optional `event.derivedPaths`, best-effort host-derived target path hints for well-known tool envelopes such as `apply_patch`; these paths may be incomplete or over-approximate what the tool will actually touch (for example, with malformed or partial inputs) - optional `event.runId` - optional `event.toolCallId` - context fields such as `ctx.agentId`, `ctx.sessionKey`, `ctx.sessionId`, `ctx.runId`, `ctx.toolKind`, `ctx.toolInputKind`, and diagnostic `ctx.trace` It can return: ```typescript type BeforeToolCallResult = { params?: Record; block?: boolean; blockReason?: string; requireApproval?: { title: string; description: string; severity?: "info" | "warning" | "critical"; timeoutMs?: number; /** @deprecated Unresolved approvals always deny. */ timeoutBehavior?: "allow" | "deny"; allowedDecisions?: Array<"allow-once" | "allow-always" | "deny">; pluginId?: string; onResolution?: ( decision: "allow-once" | "allow-always" | "deny" | "timeout" | "cancelled", ) => Promise | void; }; }; ``` Guard behavior for typed lifecycle hooks: - `block: true` is terminal and skips lower-priority handlers. - `block: false` is treated as no decision. - `params` rewrites the tool parameters for execution. - `requireApproval` pauses the agent run and asks the user through plugin approvals. `/approve` can approve both exec and plugin approvals. In Codex app-server report-mode native `PreToolUse` relays, this defers to the matching app-server approval request; see [Codex harness runtime](/plugins/codex-harness-runtime#hook-boundaries). - A lower-priority `block: true` can still block after a higher-priority hook requested approval. - `onResolution` receives the resolved decision: `allow-once`, `allow-always`, `deny`, `timeout`, or `cancelled`. See [Plugin permission requests](/plugins/plugin-permission-requests) for approval routing, decision behavior, and when to use `requireApproval` instead of optional tools or exec approvals. Plugins that need host-level policy can register trusted tool policies with `api.registerTrustedToolPolicy(...)`. These run before ordinary `before_tool_call` hooks and before normal hook decisions. Bundled trusted policies run first; installed-plugin trusted policies run next in plugin-load order; ordinary `before_tool_call` hooks run after them. Bundled plugins keep the existing trusted-policy path. Installed plugins must be explicitly enabled and declare every policy id in `contracts.trustedToolPolicies`; undeclared ids are rejected before registration. Policy ids are scoped to the registering plugin, so different plugins may reuse the same local id. Use this tier only for host-trusted gates such as workspace policy, budget enforcement, or reserved workflow safety. ### Exec environment hook `resolve_exec_env` lets plugins contribute environment variables to `exec` tool invocations before the command runs. It receives: - `event.sessionKey` - `event.toolName`, currently always `"exec"` - `event.host`, one of `"gateway"`, `"sandbox"`, or `"node"` - context fields such as `ctx.agentId`, `ctx.sessionKey`, `ctx.messageProvider`, and `ctx.channelId` Return a `Record` to merge into the exec environment. Handlers run in priority order; later results override earlier results for the same key. Hook output is filtered through the host exec environment key policy before merging. `PATH` is always dropped (command resolution and safe-bin checks depend on it). Invalid keys and dangerous host override keys such as `LD_*`, `DYLD_*`, `NODE_OPTIONS`, proxy variables (`HTTP_PROXY`, `HTTPS_PROXY`, `ALL_PROXY`, `NO_PROXY`), and TLS override variables (`NODE_TLS_REJECT_UNAUTHORIZED`, `SSL_CERT_FILE`, and similar) are dropped. The filtered plugin env is included in Gateway approval/audit metadata and forwarded to node-host execution requests. ### Tool result persistence Tool results can include structured `details` for UI rendering, diagnostics, media routing, or plugin-owned metadata. Treat `details` as runtime metadata, not prompt content: - OpenClaw strips `toolResult.details` before provider replay and compaction input so metadata does not become model context. - Persisted session entries keep only bounded `details`. Oversized details are replaced with a compact summary and `persistedDetailsTruncated: true`. - `tool_result_persist` and `before_message_write` run before the final persistence cap. Keep returned `details` small and avoid placing prompt-relevant text only in `details`; put model-visible tool output in `content`. ## Prompt and model hooks Use the phase-specific hooks for new plugins: - `before_model_resolve`: receives only the current prompt and attachment metadata. Return `providerOverride` or `modelOverride`. - `agent_turn_prepare`: receives the current prompt, prepared session messages, and any exactly-once queued injections drained for this session. Return `prependContext` or `appendContext`. - `before_prompt_build`: receives the current prompt and session messages. Return `prependContext`, `appendContext`, `systemPrompt`, `prependSystemContext`, or `appendSystemContext`. - `heartbeat_prompt_contribution`: runs only for heartbeat turns and returns `prependContext` or `appendContext`. Intended for background monitors that need to summarize current state without changing user-initiated turns. `before_agent_start` remains for compatibility. Prefer the explicit hooks above so the plugin does not depend on a legacy combined phase. `before_agent_run` runs after prompt construction and before any model input, including prompt-local image loading and `llm_input` observation. It receives the current user input as `prompt`, plus loaded session history in `messages` and the active system prompt. Return `{ outcome: "block", reason, message? }` to stop the run before the model reads the prompt. `reason` is internal; `message` is the user-facing replacement. Only `pass` and `block` outcomes are supported; unsupported decision shapes fail closed. When a run is blocked, OpenClaw stores only the replacement text in `message.content` plus non-sensitive block metadata such as the blocking plugin id and timestamp. The original user text is not retained in transcript or future context. Internal block reasons are treated as sensitive and excluded from transcript, history, broadcast, log, and diagnostics payloads. Observability should use sanitized fields such as blocker id, outcome, timestamp, or a safe category. `before_agent_start` and `agent_end` include `event.runId` when OpenClaw can identify the active run; the same value is also on `ctx.runId`. Cron-driven runs also expose `ctx.jobId` (the originating cron job id) on the agent-turn context so hooks can scope metrics, side effects, or state to a specific scheduled job. `ctx.jobId` is not part of the `before_tool_call` tool context. For channel-originated runs, `ctx.channel` and `ctx.messageProvider` identify the provider surface such as `discord` or `telegram`, while `ctx.channelId` is the conversation target identifier when OpenClaw can derive one from the session key or delivery metadata. When sender identity is available, agent hook contexts also include: - `ctx.senderId` - channel-scoped sender ID (e.g. Feishu `open_id`, Discord user ID). Populated when the run originates from a user message with known sender metadata. - `ctx.chatId` - transport-native conversation identifier (e.g. Feishu `chat_id`, Telegram `chat_id`). Populated when the originating channel provides a native conversation ID. - `ctx.channelContext.sender.id` - the same sender ID as `ctx.senderId`, under a channel-owned object plugins can extend with channel-specific fields. - `ctx.channelContext.chat.id` - the same conversation ID as `ctx.chatId`, under a channel-owned object plugins can extend with channel-specific fields. Core only defines the nested `id` fields. Channel plugins that pass richer sender or chat metadata through the inbound helper can augment `PluginHookChannelSenderContext` or `PluginHookChannelChatContext` from `openclaw/plugin-sdk/channel-inbound`: ```ts declare module "openclaw/plugin-sdk/channel-inbound" { interface PluginHookChannelSenderContext { unionId?: string; userId?: string; } } ``` Channel plugins pass those fields through the inbound SDK helper: ```ts buildChannelInboundEventContext({ // ... channelContext: { sender: { id: senderOpenId, unionId, userId }, chat: { id: chatId }, }, }); ``` These fields are optional and absent for system-originated runs (heartbeat, cron, exec-event). `ctx.senderExternalId` remains as a deprecated source-compatibility field for older plugins. Core does not populate it; new channel-specific sender identities should live under `ctx.channelContext.sender` through module augmentation. `agent_end` is an observation hook. Gateway and persistent harness paths run it fire-and-forget after the turn, while short-lived one-shot CLI paths wait for the hook promise before process cleanup so trusted plugins can flush terminal observability or capture state. The hook runner applies a 30 second timeout so a wedged plugin or embedding endpoint cannot leave the hook promise pending forever. A timeout is logged and OpenClaw continues; it does not cancel plugin-owned network work unless the plugin also uses its own abort signal. Use `model_call_started` and `model_call_ended` for provider-call telemetry that should not receive raw prompts, history, responses, headers, request bodies, or provider request IDs. These hooks include stable metadata such as `runId`, `callId`, `provider`, `model`, optional `api`/`transport`, terminal `durationMs`/`outcome`, and `upstreamRequestIdHash` when OpenClaw can derive a bounded provider request-id hash. When the runtime has resolved context-window metadata, the hook event and context also include `contextTokenBudget`, the effective token budget after model/config/agent caps, plus `contextWindowSource` and `contextWindowReferenceTokens` when a lower cap was applied. `before_agent_finalize` runs only when a harness is about to accept a natural final assistant answer. It is not the `/stop` cancellation path and does not run when the user aborts a turn. Return `{ action: "revise", reason }` to ask the harness for one more model pass before finalization, `{ action: "finalize", reason? }` to force finalization, or omit a result to continue. Handlers have a 15s default budget; on timeout, OpenClaw logs the failure and continues with the original final answer. Codex native `Stop` hooks are relayed into this hook as OpenClaw `before_agent_finalize` decisions. When returning `action: "revise"`, plugins can include `retry` metadata to make the extra model pass bounded and replay-safe: ```typescript type BeforeAgentFinalizeRetry = { instruction: string; idempotencyKey?: string; maxAttempts?: number; }; ``` `instruction` is appended to the revision reason sent to the harness. `idempotencyKey` lets the host count retries for the same plugin request across equivalent finalize decisions, and `maxAttempts` caps how many extra passes the host will allow before continuing with the natural final answer. Non-bundled plugins that need raw conversation hooks (`before_model_resolve`, `before_agent_reply`, `llm_input`, `llm_output`, `before_agent_finalize`, `agent_end`, or `before_agent_run`) must set: ```json { "plugins": { "entries": { "my-plugin": { "hooks": { "allowConversationAccess": true } } } } } ``` Prompt-mutating hooks and durable next-turn injections can be disabled per plugin with `plugins.entries..hooks.allowPromptInjection=false`. ### Session extensions and next-turn injections Workflow plugins can persist small JSON-compatible session state with `api.session.state.registerSessionExtension(...)` and update it through the Gateway `sessions.pluginPatch` method. Session rows project registered extension state through `pluginExtensions`, letting Control UI and other clients render plugin-owned status without learning plugin internals. `api.registerSessionExtension(...)` still works but is deprecated in favor of the `api.session.state` namespace. Use `api.session.workflow.enqueueNextTurnInjection(...)` when a plugin needs durable context to reach the next model turn exactly once (the top-level `api.enqueueNextTurnInjection(...)` is a deprecated alias with the same behavior). OpenClaw drains queued injections before prompt hooks, drops expired injections, and deduplicates by `idempotencyKey` per plugin. This is the right seam for approval resumes, policy summaries, background monitor deltas, and command continuations that should be visible to the model on the next turn but should not become permanent system prompt text. Cleanup semantics are part of the contract. Session extension cleanup and runtime lifecycle cleanup callbacks receive `reset`, `delete`, `disable`, or `restart`. The host removes the owning plugin's persistent session extension state and pending next-turn injections for reset/delete/disable; restart keeps durable session state while cleanup callbacks let plugins release scheduler jobs, run context, and other out-of-band resources for the old runtime generation. ## Message hooks Use message hooks for channel-level routing and delivery policy: - `message_received`: observe inbound content, sender, `threadId`, `messageId`, `senderId`, optional run/session correlation, and metadata. - `message_sending`: rewrite `content` or return `{ cancel: true }`. - `reply_payload_sending`: rewrite normalized `ReplyPayload` objects (including `presentation`, `delivery`, media refs, and text) or return `{ cancel: true }`. - `message_sent`: observe final success or failure. For audio-only TTS replies, `content` may contain the hidden spoken transcript even when the channel payload has no visible text/caption. Rewriting that `content` updates the hook-visible transcript only; it is not rendered as a media caption. `reply_payload_sending` events may include `usageState`, a best-effort live per-turn model/usage/context snapshot. Durable delivery, recovered replay, and replies without exact run correlation omit it. Message hook contexts expose stable correlation fields when available: `ctx.sessionKey`, `ctx.runId`, `ctx.messageId`, `ctx.senderId`, `ctx.trace`, `ctx.traceId`, `ctx.spanId`, `ctx.parentSpanId`, and `ctx.callDepth`. Inbound and `before_dispatch` contexts also expose reply metadata when the channel has visibility-filtered quoted message data: `replyToId`, `replyToIdFull`, `replyToBody`, `replyToSender`, and `replyToIsQuote`. Prefer these first-class fields before reading legacy metadata. Prefer typed `threadId` and `replyToId` fields before using channel-specific metadata. Decision rules: - `message_sending` with `cancel: true` is terminal. - `message_sending` with `cancel: false` is treated as no decision. - Rewritten `content` continues to lower-priority hooks unless a later hook cancels delivery. - `reply_payload_sending` runs after payload normalization and before channel delivery, including replies routed back to the originating channel. Handlers run sequentially and each handler sees the latest payload produced by higher-priority handlers. - `reply_payload_sending` payloads do not expose runtime trust markers such as `trustedLocalMedia`; plugins can edit payload shape but cannot grant local media trust. - `message_sending` can return `cancelReason` and bounded `metadata` with a cancellation. New message lifecycle APIs expose this as a suppressed delivery outcome with reason `cancelled_by_message_sending_hook`; legacy direct delivery keeps returning an empty result array for compatibility. - `message_sent` is observation-only. Handler failures are logged and do not change the delivery result. ## Install hooks Use `security.installPolicy` for operator-owned allow/block decisions. That policy runs from OpenClaw config, covers CLI install and update paths, and fails closed when enabled but unavailable. `before_install` is a plugin-runtime lifecycle hook. It runs after `security.installPolicy` only in the OpenClaw process where plugin hooks have already been loaded, such as Gateway-backed install flows. It is useful for plugin-owned observations, warnings, and compatibility checks, but it is not the primary enterprise or host security boundary for installs. The `builtinScan` field remains in the event payload for compatibility, but OpenClaw no longer runs built-in install-time dangerous-code blocking, so it is an empty `ok` result. Return additional findings or `{ block: true, blockReason }` to stop the install in that process. `block: true` is terminal. `block: false` is treated as no decision. Handler failures block the install fail-closed. ## Gateway lifecycle Use `gateway_start` to start general plugin services and `gateway_stop` to clean up long-running resources. The cron scheduler can still be loading when `gateway_start` runs, so do not use it as the baseline signal for an external cron projection. Do not rely on the internal `gateway:startup` hook for plugin-owned runtime services. `cron_reconciled` fires after the Gateway cron scheduler and its on-exit watchers have reconciled their durable state. It fires for both initial startup and scheduler replacement during config reload. The event reports `reason` (`startup` or `reload`) and the effective `enabled` state. Disabled cron still emits with `enabled: false`, allowing an external projection to clear stale wakes. Use `ctx.getCron?.()` for the exact scheduler instance that completed reconciliation; a later reload does not retarget that callback. `ctx.abortSignal` owns that same scheduler snapshot. The Gateway aborts it as soon as a newer scheduler is armed or shutdown starts. Pass it through every durable side effect and do not accept the snapshot after it aborts. This is a scheduler lifecycle signal, not a plugin-activation signal: a plugin-only hot reload does not replay it. A newly enabled consumer receives its first baseline on the next scheduler replacement or Gateway start. Like other observation hooks, `gateway_start` and `cron_reconciled` callbacks can overlap. If both handlers share plugin initialization, coordinate them with a plugin-local readiness promise rather than depending on callback order. `cron_changed` fires for Gateway-owned cron lifecycle events with a typed event payload covering `added`, `updated`, `removed`, `started`, `finished`, and `scheduled` reasons. The event carries a `PluginHookGatewayCronJob` snapshot (including `state.nextRunAtMs`, `state.lastRunStatus`, and `state.lastError` when present) plus a `PluginHookGatewayCronDeliveryStatus` of `not-requested` | `delivered` | `not-delivered` | `unknown`. Removed events are post-commit: they fire only after durable deletion succeeds and still carry the deleted job snapshot so external schedulers can reconcile state. A `scheduled` event is post-commit: it fires only after a successful durable write changes an existing job's effective `nextRunAtMs`, excluding that job's explicit `added`, `updated`, or `removed` lifecycle event. The top-level `event.nextRunAtMs` is the committed next wake; when it is absent, the job has no next wake. Treat these events as reconciliation hints, not an ordered delta log. Use them as coalescible hints to reread the scheduler last captured by `cron_reconciled`; do not adopt the scheduler from a `cron_changed` context. Keep OpenClaw as the source of truth for due checks and execution. ### Safe external cron projection Project a complete wake snapshot instead of forwarding cron event deltas. The external adapter's `replaceAll` operation must be atomic and idempotent, and it must resolve only after the host has durably accepted the snapshot. It must also honor the supplied abort signal: if the signal aborts before durable acceptance, the adapter must not accept that snapshot. This pattern keeps one latest-state worker in flight. Only `cron_reconciled` adopts a scheduler instance; `cron_changed` merely asks that worker to reread the authoritative instance, so a late hint cannot restore an older scheduler. A newer revision aborts the active host attempt before it can accept a stale snapshot. ```typescript import { setTimeout as sleep } from "node:timers/promises"; import type { OpenClawPluginApi } from "openclaw/plugin-sdk/plugin-entry"; type ExternalWake = { jobId: string; runAtMs: number }; type ExternalWakeHost = { replaceAll(wakes: readonly ExternalWake[], options: { signal: AbortSignal }): Promise; close(): Promise; }; type CronReader = { list(options: { includeDisabled: true }): Promise< Array<{ id: string; enabled?: boolean; state?: { nextRunAtMs?: number }; }> >; }; export function registerCronProjection(api: OpenClawPluginApi, host: ExternalWakeHost) { const lifecycle = new AbortController(); let cron: CronReader | undefined; let enabled = false; let hasBaseline = false; let reconciliationSignal: AbortSignal | undefined; let requestedRevision = 0; let appliedRevision = 0; let worker = Promise.resolve(); let activeAttempt: AbortController | undefined; const projectLatest = async () => { let retryMs = 1_000; while (!lifecycle.signal.aborted && appliedRevision < requestedRevision) { const ownerSignal = reconciliationSignal; if (!ownerSignal || ownerSignal.aborted) { return; } const targetRevision = requestedRevision; const attempt = new AbortController(); const signal = AbortSignal.any([lifecycle.signal, ownerSignal, attempt.signal]); activeAttempt = attempt; try { const jobs = enabled && cron ? await cron.list({ includeDisabled: true }) : []; if (signal.aborted || targetRevision !== requestedRevision) { continue; } const wakes = jobs .flatMap((job): ExternalWake[] => { const runAtMs = job.enabled === false ? undefined : job.state?.nextRunAtMs; return runAtMs === undefined ? [] : [{ jobId: job.id, runAtMs }]; }) .sort((a, b) => a.runAtMs - b.runAtMs || a.jobId.localeCompare(b.jobId)); await host.replaceAll(wakes, { signal }); if (signal.aborted || targetRevision !== requestedRevision) { continue; } appliedRevision = targetRevision; retryMs = 1_000; } catch { if (lifecycle.signal.aborted || ownerSignal.aborted) { return; } if (attempt.signal.aborted) { continue; } api.logger.warn(`external cron projection failed; retrying in ${retryMs}ms`); try { await sleep(retryMs, undefined, { signal }); } catch { if (lifecycle.signal.aborted) { return; } if (attempt.signal.aborted) { continue; } } retryMs = Math.min(retryMs * 2, 30_000); } finally { if (activeAttempt === attempt) { activeAttempt = undefined; } } } }; const requestProjection = () => { const targetRevision = ++requestedRevision; activeAttempt?.abort(); worker = worker.then(async () => { if (!lifecycle.signal.aborted && appliedRevision < targetRevision) { await projectLatest(); } }); return worker; }; api.on("cron_reconciled", (event, ctx) => { const reconciledCron = ctx.getCron?.(); if (event.enabled && !reconciledCron) { api.logger.warn("cron reconciliation did not expose a scheduler"); return; } cron = reconciledCron; enabled = event.enabled; hasBaseline = true; reconciliationSignal = ctx.abortSignal; return requestProjection(); }); api.on("cron_changed", () => { if (hasBaseline) { return requestProjection(); } }); api.on("gateway_stop", async () => { lifecycle.abort(); await worker; await host.close(); }); } ``` When `cron_reconciled` reports `enabled: false`, the same path calls `replaceAll([])` and clears stale external wakes. Retry/backoff in this example is process-local and treats runtime adapter failures as transient; validate non-retryable configuration before registration. OpenClaw does not provide an outbox for plugin hook effects. If the process exits before durable acceptance, the next Gateway start emits a new authoritative `cron_reconciled` snapshot. `gateway_stop` aborts in-flight host work, waits for the worker to settle, then closes the adapter. ## Upcoming deprecations A few hook-adjacent surfaces are deprecated but still supported. Migrate before the next major release: - **Plaintext channel envelopes** in `inbound_claim` and `message_received` handlers. Read `BodyForAgent` and the structured user-context blocks instead of parsing flat envelope text. See [Plaintext channel envelopes → BodyForAgent](/plugins/sdk-migration#active-deprecations). - **`before_agent_start`** remains for compatibility. New plugins should use `before_model_resolve` and `before_prompt_build` instead of the combined phase. - **`subagent_spawning`** remains for compatibility with older plugins, but new plugins should not return thread routing from it. Core prepares `thread: true` subagent bindings through channel session-binding adapters before `subagent_spawned` fires. - **`deactivate`** remains as a deprecated cleanup compatibility alias until after 2026-08-16. New plugins should use `gateway_stop`. - **`onResolution` in `before_tool_call`** now uses the typed `PluginApprovalResolution` union (`allow-once` / `allow-always` / `deny` / `timeout` / `cancelled`) instead of a free-form `string`. - **`api.registerSessionExtension` / `api.enqueueNextTurnInjection`** remain as top-level compatibility aliases. New plugins should use `api.session.state.registerSessionExtension(...)` and `api.session.workflow.enqueueNextTurnInjection(...)`. For the full list - memory capability registration, provider thinking profile, external auth providers, provider discovery types, task runtime accessors, and the `command-auth` → `command-status` rename - see [Plugin SDK migration → Active deprecations](/plugins/sdk-migration#active-deprecations). ## Related - [Plugin SDK migration](/plugins/sdk-migration) - active deprecations and removal timeline - [Building plugins](/plugins/building-plugins) - [Plugin SDK overview](/plugins/sdk-overview) - [Plugin entry points](/plugins/sdk-entrypoints) - [Internal hooks](/automation/hooks) - [Plugin architecture internals](/plugins/architecture-internals)