fix(hooks): guard stale idle prompts

src/hooks/atlas/boulder-continuation-injector.ts

@@ -5,12 +5,18 @@ import {
 } from "../../features/claude-code-session-state"
 import { log } from "../../shared/logger"
 import { createInternalAgentContinuationTextPart, resolveInheritedPromptTools } from "../../shared"
+import { isSessionActive } from "../shared/session-idle-settle"
 import { HOOK_NAME } from "./hook-name"
 import { BOULDER_CONTINUATION_PROMPT } from "./system-reminder-templates"
 import { resolveRecentPromptContextForSession } from "./recent-model-resolver"
 import type { BackgroundTaskStatusProvider, SessionState } from "./types"
 
-export type BoulderContinuationResult = "injected" | "skipped_background_tasks" | "skipped_agent_unavailable" | "failed"
+export type BoulderContinuationResult =
+  | "injected"
+  | "skipped_active_session"
+  | "skipped_background_tasks"
+  | "skipped_agent_unavailable"
+  | "failed"
 
 const ACTIVE_BACKGROUND_TASK_STATUSES = new Set(["pending", "running"])
 
@@ -68,11 +74,16 @@ export async function injectBoulderContinuation(input: {
 			sessionID,
 			agent: continuationAgent ?? agent ?? "unknown",
 		})
-		return "skipped_agent_unavailable"
-	}
+    return "skipped_agent_unavailable"
+  }
 
-	try {
-		log(`[${HOOK_NAME}] Injecting boulder continuation`, { sessionID, planName, remaining })
+  try {
+    if (await isSessionActive(ctx.client, sessionID)) {
+      log(`[${HOOK_NAME}] Skipped injection: session is active`, { sessionID })
+      return "skipped_active_session"
+    }
+
+    log(`[${HOOK_NAME}] Injecting boulder continuation`, { sessionID, planName, remaining })
 
     const promptContext = await resolveRecentPromptContextForSession(ctx, sessionID)
     const inheritedTools = resolveInheritedPromptTools(sessionID, promptContext.tools)

src/hooks/atlas/idle-event.ts

@@ -19,7 +19,7 @@ import { isSessionInBoulderLineage } from "./boulder-session-lineage"
 import { createInternalAgentContinuationTextPart } from "../../shared"
 import { getAgentConfigKey } from "../../shared/agent-display-names"
 import { log } from "../../shared/logger"
-import { settleAfterSessionIdle } from "../shared/session-idle-settle"
+import { shouldPromptAfterSessionIdle } from "../shared/session-idle-settle"
 import { injectBoulderContinuation } from "./boulder-continuation-injector"
 import { HOOK_NAME } from "./hook-name"
 import { resolveActiveBoulderSession } from "./resolve-active-boulder-session"
@@ -283,6 +283,11 @@ export async function handleAtlasSessionIdle(input: {
       boulderState.agent ?? (isAgentRegistered("atlas") ? "atlas" : undefined),
     )
     if (atlasAgent && isAgentRegistered(atlasAgent)) {
+      if (!(await shouldPromptAfterSessionIdle(ctx.client, sessionID, options?.idleSettleMs))) {
+        log(`[${HOOK_NAME}] Boulder completion nudge skipped because session is active`, { sessionID })
+        return
+      }
+
       await ctx.client.session.promptAsync({
         path: { id: sessionID },
         body: {
@@ -379,7 +384,10 @@ export async function handleAtlasSessionIdle(input: {
     return
   }
 
-  await settleAfterSessionIdle(options?.idleSettleMs)
+  if (!(await shouldPromptAfterSessionIdle(ctx.client, sessionID, options?.idleSettleMs))) {
+    log(`[${HOOK_NAME}] Skipped: session became active during idle settle`, { sessionID })
+    return
+  }
 
   await injectContinuation({
     ctx,

src/hooks/ralph-loop/ralph-loop-event-handler.ts

@@ -1,6 +1,7 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { log } from "../../shared/logger"
 import { resolveMessageEventSessionID, resolveSessionEventID } from "../../shared/event-session-id"
+import { isSessionActive } from "../shared/session-idle-settle"
 import type { RalphLoopOptions, RalphLoopState } from "./types"
 import { HOOK_NAME } from "./constants"
 import { handleDetectedCompletion } from "./completion-handler"
@@ -327,6 +328,10 @@ export function createRalphLoopEventHandler(
 					})
 					return
 				}
+				if (await isSessionActive(ctx.client, sessionID)) {
+					log(`[${HOOK_NAME}] Skipped: session became active during settle window`, { sessionID })
+					return
+				}
 				if (stateAfterSettle.verification_pending) {
 					log(`[${HOOK_NAME}] Skipped: state entered verification_pending during settle window`, { sessionID })
 					return
@@ -484,6 +489,10 @@ export function createRalphLoopEventHandler(
 					})
 					return
 				}
+				if (await isSessionActive(ctx.client, sessionID)) {
+					log(`[${HOOK_NAME}] Skipped: session became active during settle window`, { sessionID })
+					return
+				}
 				if (stateAfterSettle.verification_pending) {
 					log(`[${HOOK_NAME}] Skipped: state entered verification_pending during settle window`, { sessionID })
 					return

src/hooks/team-session-events/team-idle-wake-hint.test.ts

@@ -184,6 +184,41 @@ describe("createTeamIdleWakeHint", () => {
     expect(promptInput.body.parts[0]?.text).not.toContain("second message body")
   })
 
+  test("#given stale idle event but member session is busy #when wake hint checks status #then it does not start an overlapping reply", async () => {
+    // given
+    const baseDir = await createTemporaryBaseDir()
+    const config = createConfig(baseDir)
+    const teamRunId = randomUUID()
+    await seedRuntimeState(createRuntimeState(teamRunId), config)
+    await seedUnreadMessage(teamRunId, config, randomUUID(), "first message body", 100)
+
+    const promptAsyncSpy = mock(async (_input: WakeHintPromptInput) => ({}))
+    const handler = createTeamIdleWakeHint({
+      directory: "/tmp/project",
+      client: {
+        session: {
+          promptAsync: promptAsyncSpy,
+          status: async () => ({
+            data: {
+              "member-session": { type: "busy" },
+            },
+          }),
+        },
+      },
+    }, config, { idleSettleMs: 0 })
+
+    // when
+    await handler({
+      event: {
+        type: "session.idle",
+        properties: { sessionID: "member-session" },
+      },
+    })
+
+    // then
+    expect(promptAsyncSpy).toHaveBeenCalledTimes(0)
+  })
+
   test("pins the recipient's resolved subagent_type and model on the wake-hint promptAsync", async () => {
     // given
     const baseDir = await createTemporaryBaseDir()

src/hooks/team-session-events/team-idle-wake-hint.ts

@@ -9,7 +9,7 @@ import {
 } from "../../features/team-mode/member-session-routing"
 import { resolveSessionEventID } from "../../shared/event-session-id"
 import { log } from "../../shared/logger"
-import { settleAfterSessionIdle } from "../shared/session-idle-settle"
+import { shouldPromptAfterSessionIdle } from "../shared/session-idle-settle"
 
 type PromptAsyncInput = {
   path: { id: string }
@@ -27,6 +27,7 @@ type TeamIdleWakeHintContext = {
   client: {
     session: {
       promptAsync?: (input: PromptAsyncInput) => Promise<unknown>
+      status?: () => Promise<unknown>
     }
   }
 }
@@ -99,7 +100,16 @@ export function createTeamIdleWakeHint(ctx: TeamIdleWakeHintContext, config: Tea
       }
 
       applyMemberSessionRouting(sessionID, memberEntry)
-      await settleAfterSessionIdle(options?.idleSettleMs)
+      if (!(await shouldPromptAfterSessionIdle(ctx.client, sessionID, options?.idleSettleMs))) {
+        log("team idle wake hint skipped because session is active", {
+          event: "team-mode-idle-wake-hint-active-session",
+          teamRunId: runtimeState.teamRunId,
+          memberName: memberEntry.name,
+          sessionID,
+          unreadCount: unreadMessages.length,
+        })
+        return
+      }
 
       await ctx.client.session.promptAsync({
         path: { id: sessionID },

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

@@ -21,6 +21,7 @@ import {
   getAgentConfigKey,
   normalizeAgentForPromptKey,
 } from "../../shared/agent-display-names"
+import { isSessionActive } from "../shared/session-idle-settle"
 
 import {
   CONTINUATION_PROMPT,
@@ -165,6 +166,11 @@ ${todoList}`
     return
   }
 
+  if (await isSessionActive(ctx.client, sessionID)) {
+    log(`[${HOOK_NAME}] Skipped injection: session is active before prompt`, { sessionID })
+    return
+  }
+
   if (injectionState) {
     injectionState.inFlight = true
   }

src/hooks/unstable-agent-babysitter/unstable-agent-babysitter-hook.ts

@@ -12,7 +12,7 @@ import {
   isUnstableTask,
   THINKING_SUMMARY_MAX_CHARS,
 } from "./task-message-analyzer"
-import { settleAfterSessionIdle } from "../shared/session-idle-settle"
+import { shouldPromptAfterSessionIdle } from "../shared/session-idle-settle"
 
 const HOOK_NAME = "unstable-agent-babysitter"
 const DEFAULT_TIMEOUT_MS = 120000
@@ -49,6 +49,7 @@ type BabysitterContext = {
         }
         query?: { directory?: string }
       }) => Promise<unknown>
+      status?: () => Promise<unknown>
     }
   }
 }
@@ -215,7 +216,10 @@ export function createUnstableAgentBabysitterHook(ctx: BabysitterContext, option
           ? { providerID: model.providerID, modelID: model.modelID }
           : undefined
         const launchVariant = model?.variant
-        await settleAfterSessionIdle(options.idleSettleMs)
+        if (!(await shouldPromptAfterSessionIdle(ctx.client, mainSessionID, options.idleSettleMs))) {
+          log(`[${HOOK_NAME}] Reminder skipped because main session is active`, { taskId: task.id, sessionID: mainSessionID })
+          continue
+        }
 
         await ctx.client.session.promptAsync({
           path: { id: mainSessionID },