fix(hooks): settle idle prompt continuations

src/hooks/unstable-agent-babysitter/index.test.ts

@@ -63,6 +63,41 @@ describe("unstable-agent-babysitter hook", () => {
     _resetForTesting()
   })
 
+  test("settles idle before injecting a reminder", async () => {
+    // #given
+    setMainSession("main-1")
+    const promptCalls: Array<{ input: unknown }> = []
+    const ctx = createMockPluginInput({
+      messagesBySession: {
+        "main-1": [
+          { info: { agent: "sisyphus", model: { providerID: "openai", modelID: "gpt-4" } } },
+        ],
+        "bg-1": [
+          { info: { role: "assistant" }, parts: [{ type: "thinking", thinking: "deep thought" }] },
+        ],
+      },
+      promptCalls,
+    })
+    const backgroundManager = createBackgroundManager([createTask()])
+    const hook = createUnstableAgentBabysitterHook(ctx, {
+      backgroundManager,
+      config: { timeout_ms: 120000 },
+      idleSettleMs: 50,
+    })
+
+    // #when
+    const startedAt = Date.now()
+    const eventPromise = hook.event({ event: { type: "session.idle", properties: { sessionID: "main-1" } } })
+    await Promise.resolve()
+
+    // #then
+    expect(promptCalls.length).toBe(0)
+
+    await eventPromise
+    expect(Date.now() - startedAt).toBeGreaterThanOrEqual(45)
+    expect(promptCalls.length).toBe(1)
+  })
+
   test("fires reminder for hung gemini task", async () => {
     // #given
     setMainSession("main-1")

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

@@ -11,6 +11,7 @@ import {
   isUnstableTask,
   THINKING_SUMMARY_MAX_CHARS,
 } from "./task-message-analyzer"
+import { settleAfterSessionIdle } from "../shared/session-idle-settle"
 
 const HOOK_NAME = "unstable-agent-babysitter"
 const DEFAULT_TIMEOUT_MS = 120000
@@ -54,6 +55,7 @@ type BabysitterContext = {
 type BabysitterOptions = {
   backgroundManager: Pick<BackgroundManager, "getTasksByParentSession">
   config?: BabysittingConfig
+  idleSettleMs?: number
 }
 
 
@@ -212,6 +214,7 @@ export function createUnstableAgentBabysitterHook(ctx: BabysitterContext, option
           ? { providerID: model.providerID, modelID: model.modelID }
           : undefined
         const launchVariant = model?.variant
+        await settleAfterSessionIdle(options.idleSettleMs)
 
         await ctx.client.session.promptAsync({
           path: { id: mainSessionID },