fix(todo-continuation-enforcer): tighten post-compaction guard with session-agent fallback

Refine continuation agent resolution to prefer session-state agent fallback while keeping compaction-specific protection. Replace sticky boolean compaction flag with a short-lived timestamp guard so unresolved agents are blocked only during the immediate post-compaction window, avoiding long-lived suppression and preserving existing continuation behavior.

src/hooks/todo-continuation-enforcer/compaction-guard.ts

@@ -0,0 +1,10 @@
+import { COMPACTION_GUARD_MS } from "./constants"
+import type { SessionState } from "./types"
+
+export function isCompactionGuardActive(state: SessionState, now: number): boolean {
+  if (!state.recentCompactionAt) {
+    return false
+  }
+
+  return now - state.recentCompactionAt < COMPACTION_GUARD_MS
+}

src/hooks/todo-continuation-enforcer/constants.ts

@@ -17,6 +17,7 @@ export const TOAST_DURATION_MS = 900
 export const COUNTDOWN_GRACE_PERIOD_MS = 500
 
 export const ABORT_WINDOW_MS = 3000
+export const COMPACTION_GUARD_MS = 60_000
 export const CONTINUATION_COOLDOWN_MS = 5_000
 export const MAX_STAGNATION_COUNT = 3
 export const MAX_CONSECUTIVE_FAILURES = 5

src/hooks/todo-continuation-enforcer/continuation-injection.ts

@@ -1,6 +1,7 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 
 import type { BackgroundManager } from "../../features/background-agent"
+import { getSessionAgent } from "../../features/claude-code-session-state"
 import {
   createInternalAgentTextPart,
   normalizeSDKResponse,
@@ -20,6 +21,7 @@ import {
   DEFAULT_SKIP_AGENTS,
   HOOK_NAME,
 } from "./constants"
+import { isCompactionGuardActive } from "./compaction-guard"
 import { getMessageDir } from "./message-directory"
 import { getIncompleteCount } from "./todo"
 import type { ResolvedMessageInfo, Todo } from "./types"
@@ -88,7 +90,7 @@ export async function injectContinuation(args: {
     return
   }
 
-  let agentName = resolvedInfo?.agent
+  let agentName = resolvedInfo?.agent ?? getSessionAgent(sessionID)
   let model = resolvedInfo?.model
   let tools = resolvedInfo?.tools
 
@@ -122,7 +124,7 @@ export async function injectContinuation(args: {
 
   if (!agentName) {
     const compactionState = sessionStateStore.getExistingState(sessionID)
-    if (compactionState?.hasRecentCompaction) {
+    if (compactionState && isCompactionGuardActive(compactionState, Date.now())) {
       log(`[${HOOK_NAME}] Skipped: agent unknown after compaction`, { sessionID })
       return
     }

src/hooks/todo-continuation-enforcer/handler.ts

@@ -67,9 +67,9 @@ export function createTodoContinuationHandler(args: {
       const sessionID = (props?.sessionID ?? (props?.info as { id?: string } | undefined)?.id) as string | undefined
       if (sessionID) {
         const state = sessionStateStore.getState(sessionID)
-        state.hasRecentCompaction = true
+        state.recentCompactionAt = Date.now()
         sessionStateStore.cancelCountdown(sessionID)
-        log(`[${HOOK_NAME}] Session compacted: marked hasRecentCompaction`, { sessionID })
+        log(`[${HOOK_NAME}] Session compacted: marked recentCompactionAt`, { sessionID })
       }
       return
     }

src/hooks/todo-continuation-enforcer/idle-event.ts

@@ -1,7 +1,6 @@
 import type { PluginInput } from "@opencode-ai/plugin"
-
 import type { BackgroundManager } from "../../features/background-agent"
-import type { ToolPermission } from "../../features/hook-message-injector"
+import { getSessionAgent } from "../../features/claude-code-session-state"
 import { normalizeSDKResponse } from "../../shared"
 import { log } from "../../shared/logger"
 import { getAgentConfigKey } from "../../shared/agent-display-names"
@@ -19,6 +18,8 @@ import { hasUnansweredQuestion } from "./pending-question-detection"
 import { shouldStopForStagnation } from "./stagnation-detection"
 import { getIncompleteCount } from "./todo"
 import type { MessageInfo, ResolvedMessageInfo, Todo } from "./types"
+import { resolveLatestMessageInfo } from "./resolve-message-info"
+import { isCompactionGuardActive } from "./compaction-guard"
 import type { SessionStateStore } from "./session-state"
 import { startCountdown } from "./countdown"
 
@@ -119,10 +120,7 @@ export async function handleSessionIdle(args: {
     && Date.now() - state.lastInjectedAt >= FAILURE_RESET_WINDOW_MS
   ) {
     state.consecutiveFailures = 0
-    log(`[${HOOK_NAME}] Reset consecutive failures after recovery window`, {
-      sessionID,
-      failureResetWindowMs: FAILURE_RESET_WINDOW_MS,
-    })
+    log(`[${HOOK_NAME}] Reset consecutive failures after recovery window`, { sessionID, failureResetWindowMs: FAILURE_RESET_WINDOW_MS })
   }
 
   if (state.consecutiveFailures >= MAX_CONSECUTIVE_FAILURES) {
@@ -147,39 +145,32 @@ export async function handleSessionIdle(args: {
 
   let resolvedInfo: ResolvedMessageInfo | undefined
   try {
-    const messagesResp = await ctx.client.session.messages({
-      path: { id: sessionID },
-    })
-    const messages = normalizeSDKResponse(messagesResp, [] as Array<{ info?: MessageInfo }>)
-    for (let i = messages.length - 1; i >= 0; i--) {
-      const info = messages[i].info
-      if (info?.agent === "compaction") {
-        continue
-      }
-      if (info?.agent || info?.model || (info?.modelID && info?.providerID)) {
-        resolvedInfo = {
-          agent: info.agent,
-          model: info.model ?? (info.providerID && info.modelID ? { providerID: info.providerID, modelID: info.modelID } : undefined),
-          tools: info.tools as Record<string, ToolPermission> | undefined,
-        }
-        break
-      }
-    }
+    resolvedInfo = await resolveLatestMessageInfo(ctx, sessionID)
   } catch (error) {
     log(`[${HOOK_NAME}] Failed to fetch messages for agent check`, { sessionID, error: String(error) })
   }
 
-  log(`[${HOOK_NAME}] Agent check`, { sessionID, agentName: resolvedInfo?.agent, skipAgents, hasRecentCompaction: state.hasRecentCompaction })
+  const sessionAgent = getSessionAgent(sessionID)
+  if (!resolvedInfo?.agent && sessionAgent) {
+    resolvedInfo = { ...resolvedInfo, agent: sessionAgent }
+  }
+
+  const compactionGuardActive = isCompactionGuardActive(state, Date.now())
+
+  log(`[${HOOK_NAME}] Agent check`, { sessionID, agentName: resolvedInfo?.agent, skipAgents, compactionGuardActive })
 
   const resolvedAgentName = resolvedInfo?.agent
   if (resolvedAgentName && skipAgents.some(s => getAgentConfigKey(s) === getAgentConfigKey(resolvedAgentName))) {
     log(`[${HOOK_NAME}] Skipped: agent in skipAgents list`, { sessionID, agent: resolvedAgentName })
     return
   }
-  if (state.hasRecentCompaction && !resolvedInfo?.agent) {
+  if (compactionGuardActive && !resolvedInfo?.agent) {
     log(`[${HOOK_NAME}] Skipped: compaction occurred but no agent info resolved`, { sessionID })
     return
   }
+  if (state.recentCompactionAt && resolvedInfo?.agent) {
+    state.recentCompactionAt = undefined
+  }
 
   if (isContinuationStopped?.(sessionID)) {
     log(`[${HOOK_NAME}] Skipped: continuation stopped for session`, { sessionID })
@@ -195,7 +186,6 @@ export async function handleSessionIdle(args: {
   if (shouldStopForStagnation({ sessionID, incompleteCount, progressUpdate })) {
     return
   }
-
   startCountdown({
     ctx,
     sessionID,

src/hooks/todo-continuation-enforcer/resolve-message-info.ts

@@ -0,0 +1,31 @@
+import type { PluginInput } from "@opencode-ai/plugin"
+
+import { normalizeSDKResponse } from "../../shared"
+
+import type { MessageInfo, ResolvedMessageInfo } from "./types"
+
+export async function resolveLatestMessageInfo(
+  ctx: PluginInput,
+  sessionID: string
+): Promise<ResolvedMessageInfo | undefined> {
+  const messagesResp = await ctx.client.session.messages({
+    path: { id: sessionID },
+  })
+  const messages = normalizeSDKResponse(messagesResp, [] as Array<{ info?: MessageInfo }>)
+
+  for (let i = messages.length - 1; i >= 0; i--) {
+    const info = messages[i].info
+    if (info?.agent === "compaction") {
+      continue
+    }
+    if (info?.agent || info?.model || (info?.modelID && info?.providerID)) {
+      return {
+        agent: info.agent,
+        model: info.model ?? (info.providerID && info.modelID ? { providerID: info.providerID, modelID: info.modelID } : undefined),
+        tools: info.tools,
+      }
+    }
+  }
+
+  return undefined
+}

src/hooks/todo-continuation-enforcer/types.ts

@@ -35,7 +35,7 @@ export interface SessionState {
   inFlight?: boolean
   stagnationCount: number
   consecutiveFailures: number
-  hasRecentCompaction?: boolean
+  recentCompactionAt?: number
 }
 
 export interface MessageInfo {