fix(claude): retain final usage when an API-error turn fails

Publish the converted result totals before the failure event so the
existing usage handler preserves work done earlier in the turn.

docs/android.md

@@ -174,7 +174,7 @@ REACT_NATIVE_PACKAGER_HOSTNAME=localhost \
 
 This is the Android counterpart of the iOS local-simulator flow in [development.md](development.md): on iOS the simulator shares the Mac's loopback so `localhost:<port>` works directly; on Android you need `10.0.2.2` or `adb reverse`.
 
-## Inverted timeline scrolling
+## Inverted timeline selection
 
 Android focus and selection visibility requests must not reposition inverted timelines. The
 `modules/paseo-scroll` package keeps React Native's scroll manager interface and returns zero for
@@ -183,16 +183,6 @@ Native's Android list uses `scale: -1`, which decomposes into a 180-degree rotat
 `scaleY`; checking the scale property alone misses it. Dragging and explicit scroll
 commands still work; non-inverted scroll views keep Android's default behavior.
 
-Nested panels also keep their edge overshoot and unconsumed flings inside the panel instead of
-moving the inverted timeline in the opposite direction. Nested-scroll registration and scrolling
-inside the panel are preserved. Run the native selection and nested-scroll regressions after prebuild:
-
-```bash
-cd packages/app/android
-./gradlew :paseo-scroll:connectedDebugAndroidTest \
-  --no-daemon --max-workers=2 -Dorg.gradle.parallel=false
-```
-
 Register this package before React Native's core package through its Expo config plugin. Normal
 Android builds use the prebuilt `react-android` library, so patching Java under `node_modules` does
 not change the shipped scroll view. Keep this behavior in the app's compiled native module.

packages/app/e2e/browser/composer-recall.spec.ts

@@ -3,7 +3,7 @@ import {
   composerLocator,
   expectComposerDraft,
   expectComposerVisible,
-  submitMessage,
+  fillComposerDraft,
   typeIntoFocusedComposer,
 } from "../support/helpers/composer";
 import { openAgentRoute, seedMockAgentWorkspace } from "../support/helpers/mock-agent";
@@ -12,8 +12,14 @@ function userMessages(page: Page) {
   return page.getByTestId("user-message");
 }
 
+async function sendDraftWhenReady(page: Page) {
+  await expect(page.getByRole("button", { name: "Send message", exact: true })).toBeEnabled();
+  await pressInComposer(page, "Enter");
+}
+
 async function sendAndWaitForMessage(page: Page, text: string, expectedCount: number) {
-  await submitMessage(page, text);
+  await fillComposerDraft(page, text);
+  await sendDraftWhenReady(page);
   await expect(userMessages(page)).toHaveCount(expectedCount, { timeout: 30_000 });
   await expectComposerDraft(page, "");
 }
@@ -49,7 +55,7 @@ test.describe("Composer recall", () => {
       await pressInComposer(page, "ArrowUp");
       await expectComposerDraft(page, "add tests for login");
 
-      await pressInComposer(page, "Enter");
+      await sendDraftWhenReady(page);
       await expect(userMessages(page)).toHaveCount(3, { timeout: 30_000 });
       await expect(userMessages(page).last()).toContainText("add tests for login");
     } finally {

packages/app/modules/paseo-scroll/android/src/androidTest/AndroidManifest.xml

@@ -1,5 +0,0 @@
-<manifest xmlns:android="http://schemas.android.com/apk/res/android">
-  <application>
-    <activity android:name="sh.paseo.scroll.NestedScrollActivity" android:theme="@android:style/Theme.Material.Light.NoActionBar" android:exported="false" />
-  </application>
-</manifest>

packages/app/modules/paseo-scroll/android/src/androidTest/java/sh/paseo/scroll/NestedScrollTest.kt

@@ -1,134 +0,0 @@
-package sh.paseo.scroll
-
-import android.app.Activity
-import android.content.Intent
-import android.os.SystemClock
-import android.view.View
-import android.view.ViewGroup
-import android.widget.FrameLayout
-import androidx.test.ext.junit.runners.AndroidJUnit4
-import androidx.test.platform.app.InstrumentationRegistry
-import com.facebook.react.bridge.JavaOnlyArray
-import com.facebook.react.bridge.JavaOnlyMap
-import com.facebook.react.soloader.OpenSourceMergedSoMapping
-import com.facebook.react.uimanager.DisplayMetricsHolder
-import com.facebook.react.uimanager.ReactStylesDiffMap
-import com.facebook.react.uimanager.ThemedReactContext
-import com.facebook.react.views.scroll.ReactScrollView
-import com.facebook.react.views.scroll.ReactScrollViewManager
-import com.facebook.soloader.SoLoader
-import org.junit.Assert.*
-import org.junit.Test
-import org.junit.runner.RunWith
-
-class NestedScrollActivity : Activity()
-
-@RunWith(AndroidJUnit4::class)
-class NestedScrollTest {
-  @Test fun invertedTimelineDoesNotConsumePanelOvershoot() = withNestedScroll(inverted = true) { parent, child ->
-    val before = parent.scrollY
-    assertTrue(child.startNestedScroll(View.SCROLL_AXIS_VERTICAL))
-    child.scrollTo(0, 600)
-    assertEquals(600, child.scrollY)
-    assertTrue(child.dispatchNestedScroll(0, 0, 0, 100, null))
-    assertEquals("Panel overshoot must not move the inverted timeline", before, parent.scrollY)
-    child.scrollTo(0, 0)
-    assertTrue(child.dispatchNestedScroll(0, 0, 0, -100, null))
-    assertEquals("Overshoot at either edge must stay inside the panel", before, parent.scrollY)
-    child.stopNestedScroll()
-  }
-
-  @Test fun ordinaryParentStillConsumesPanelOvershoot() = withNestedScroll(inverted = false) { parent, child ->
-    val before = parent.scrollY
-    assertTrue(child.startNestedScroll(View.SCROLL_AXIS_VERTICAL))
-    child.scrollTo(0, 600)
-    assertEquals(600, child.scrollY)
-    assertTrue(child.dispatchNestedScroll(0, 0, 0, 100, null))
-    assertEquals(before + 100, parent.scrollY)
-    child.stopNestedScroll()
-  }
-
-  @Test fun panelCanStillScrollInsideInvertedTimeline() = withNestedScroll(inverted = true) { parent, child ->
-    val before = parent.scrollY
-    assertTrue(child.startNestedScroll(View.SCROLL_AXIS_VERTICAL))
-    child.scrollTo(0, 100)
-    assertTrue(child.dispatchNestedScroll(0, 100, 0, 0, null))
-    assertEquals(100, child.scrollY)
-    assertEquals(before, parent.scrollY)
-    child.stopNestedScroll()
-    parent.scrollTo(0, before + 100)
-    assertEquals(before + 100, parent.scrollY)
-  }
-
-  @Test fun invertedTimelineAbsorbsUnconsumedPanelFling() = checkFling(inverted = true)
-
-  @Test fun ordinaryParentStillAcceptsUnconsumedPanelFling() = checkFling(inverted = false)
-
-  private fun checkFling(inverted: Boolean) = withNestedScroll(
-    inverted = inverted,
-    afterFrames = { parent ->
-      if (inverted) assertEquals("Panel fling must not move the inverted timeline", 400, parent.scrollY)
-      else assertTrue("Control fling must move an ordinary parent", parent.scrollY > 400)
-    }
-  ) { parent, child ->
-    parent.scrollTo(0, 400)
-    assertTrue(child.startNestedScroll(View.SCROLL_AXIS_VERTICAL))
-    child.scrollTo(0, 600)
-    assertEquals(600, child.scrollY)
-    assertTrue(child.dispatchNestedFling(0f, 1500f, false))
-    child.stopNestedScroll()
-  }
-
-  private fun withNestedScroll(
-    inverted: Boolean,
-    afterFrames: ((ReactScrollView) -> Unit)? = null,
-    check: (ReactScrollView, ReactScrollView) -> Unit
-  ) {
-    val instrumentation = InstrumentationRegistry.getInstrumentation()
-    val activity = instrumentation.startActivitySync(
-      Intent(instrumentation.context, NestedScrollActivity::class.java).addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
-    )
-    lateinit var parent: ReactScrollView
-    try {
-      instrumentation.runOnMainSync {
-        val appContext = instrumentation.targetContext
-        DisplayMetricsHolder.initDisplayMetricsIfNotInitialized(appContext)
-        SoLoader.init(appContext, OpenSourceMergedSoMapping)
-        val reactContext = ScrollTestContext(appContext)
-        val context = ThemedReactContext(reactContext, appContext)
-        val manager = PaseoScrollPackage().createViewManager(reactContext, ReactScrollViewManager.REACT_CLASS) as ReactScrollViewManager
-        parent = manager.createViewInstance(context)
-        val child = manager.createViewInstance(context).apply { isNestedScrollingEnabled = true }
-        val panelContent = View(context)
-        child.addView(panelContent, FrameLayout.LayoutParams(300, 800))
-        val content = FrameLayout(context)
-        content.addView(child, FrameLayout.LayoutParams(300, 200).apply { topMargin = 500 })
-        parent.addView(content, FrameLayout.LayoutParams(300, 2000))
-        panelContent.measure(exact(300), exact(800))
-        panelContent.layout(0, 0, 300, 800)
-        child.measure(exact(300), exact(200))
-        child.layout(0, 500, 300, 700)
-        content.measure(exact(300), exact(2000))
-        content.layout(0, 0, 300, 2000)
-        parent.measure(exact(300), exact(400))
-        parent.layout(0, 0, 300, 400)
-        // The same transform React Native applies to an inverted FlatList on Android.
-        manager.updateProperties(parent, ReactStylesDiffMap(JavaOnlyMap.of(
-          "transform", JavaOnlyArray.of(JavaOnlyMap.of("scale", if (inverted) -1.0 else 1.0))
-        )))
-        activity.setContentView(parent, ViewGroup.LayoutParams(300, 400))
-        parent.scrollTo(0, 400)
-        check(parent, child)
-      }
-      if (afterFrames != null) {
-        // Let the framework's real fling animation advance, with an ordinary-parent control.
-        SystemClock.sleep(500)
-        instrumentation.runOnMainSync { afterFrames(parent) }
-      }
-    } finally {
-      instrumentation.runOnMainSync { activity.finish() }
-    }
-  }
-
-  private fun exact(size: Int) = View.MeasureSpec.makeMeasureSpec(size, View.MeasureSpec.EXACTLY)
-}

packages/app/modules/paseo-scroll/android/src/androidTest/java/sh/paseo/scroll/ScrollSelectionTest.kt

@@ -8,6 +8,7 @@ import android.widget.FrameLayout
 import android.widget.TextView
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import androidx.test.platform.app.InstrumentationRegistry
+import com.facebook.react.bridge.BridgeReactContext
 import com.facebook.react.bridge.JavaOnlyArray
 import com.facebook.react.bridge.JavaOnlyMap
 import com.facebook.react.soloader.OpenSourceMergedSoMapping
@@ -69,7 +70,7 @@ class ScrollSelectionTest {
       val appContext = instrumentation.targetContext
       DisplayMetricsHolder.initDisplayMetricsIfNotInitialized(appContext)
       SoLoader.init(appContext, OpenSourceMergedSoMapping)
-      val reactContext = ScrollTestContext(appContext)
+      val reactContext = BridgeReactContext(appContext)
       val context = ThemedReactContext(reactContext, appContext)
       val manager = PaseoScrollPackage().createViewManager(reactContext, ReactScrollViewManager.REACT_CLASS) as ReactScrollViewManager
       val scroll = manager.createViewInstance(context)

packages/app/modules/paseo-scroll/android/src/androidTest/java/sh/paseo/scroll/ScrollTestContext.java

@@ -1,19 +0,0 @@
-package sh.paseo.scroll;
-
-import android.content.Context;
-import com.facebook.react.bridge.BridgeReactContext;
-import com.facebook.react.uimanager.events.BlackHoleEventDispatcher;
-import com.facebook.react.uimanager.events.EventDispatcher;
-import com.facebook.react.uimanager.events.EventDispatcherProvider;
-
-/** Native-only tests use RN's dispatcher for a context without a JS instance. */
-final class ScrollTestContext extends BridgeReactContext implements EventDispatcherProvider {
-  ScrollTestContext(Context context) {
-    super(context);
-  }
-
-  @Override
-  public EventDispatcher getEventDispatcher() {
-    return BlackHoleEventDispatcher.INSTANCE;
-  }
-}

packages/app/modules/paseo-scroll/android/src/main/java/sh/paseo/scroll/PaseoScrollPackage.kt

@@ -2,7 +2,6 @@ package sh.paseo.scroll
 
 import android.graphics.Matrix
 import android.graphics.Rect
-import android.view.View
 import com.facebook.react.ReactPackage
 import com.facebook.react.ViewManagerOnDemandReactPackage
 import com.facebook.react.bridge.NativeModule
@@ -31,30 +30,13 @@ private class PaseoScrollViewManager : ReactScrollViewManager() {
 private class PaseoScrollView(context: ThemedReactContext) : ReactScrollView(context) {
   private val transformValues = FloatArray(9)
 
-  private val isInverted: Boolean
-    get() {
-      // RN's Android scale: -1 becomes a 180-degree rotation with positive scaleY.
-      matrix.getValues(transformValues)
-      return transformValues[Matrix.MSCALE_Y] < 0
-    }
-
   // Both RN focus handling and Android selection visibility requests use this calculation.
   // Its coordinates ignore inversion. Keep focus/selection bookkeeping, but leave timeline
   // movement to user gestures and explicit scroll commands.
   override fun computeScrollDeltaToGetChildRectOnScreen(rect: Rect): Int {
-    if (isInverted) return 0
+    // RN's Android scale: -1 becomes a 180-degree rotation with positive scaleY.
+    matrix.getValues(transformValues)
+    if (transformValues[Matrix.MSCALE_Y] < 0) return 0
     return super.computeScrollDeltaToGetChildRectOnScreen(rect)
   }
-
-  // A nested panel's remaining delta uses its own visual direction. Consuming it in
-  // an inverted timeline moves the timeline the opposite way when the panel hits an edge.
-  override fun onNestedScroll(target: View, dxConsumed: Int, dyConsumed: Int, dxUnconsumed: Int, dyUnconsumed: Int) {
-    if (isInverted) return
-    super.onNestedScroll(target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed)
-  }
-
-  override fun onNestedFling(target: View, velocityX: Float, velocityY: Float, consumed: Boolean): Boolean {
-    if (isInverted && !consumed) return true
-    return super.onNestedFling(target, velocityX, velocityY, consumed)
-  }
 }

packages/server/src/server/agent/providers/claude/agent.error-result.test.ts

@@ -0,0 +1,190 @@
+import { expect, test } from "vitest";
+import { createTestLogger } from "../../../../test-utils/test-logger.js";
+import { collectSessionTurnEvents } from "../test-utils/session-stream-adapter.js";
+import { ClaudeAgentClient } from "./agent.js";
+import type { ClaudeQueryFactory } from "./query.js";
+
+const LIMIT = "You've hit your session limit · resets 5:20pm (Asia/Singapore)";
+
+interface ScriptedTurn {
+  // An API error reply as Claude Code writes it: a synthetic assistant message with `error`.
+  errorReply?: string;
+  // Assistant text the model wrote before or after it.
+  before?: string;
+  after?: string;
+  isError: boolean;
+  usage?: {
+    inputTokens: number;
+    cachedInputTokens: number;
+    outputTokens: number;
+    totalCostUsd: number;
+  };
+}
+
+// A query dependency that speaks Claude Code's stream interface, one scripted turn per prompt.
+function scriptedQuery(turns: ScriptedTurn[]): ClaudeQueryFactory {
+  return ({ prompt }) => {
+    let index = 0;
+    const assistant = (id: string, text: string, error?: string) => ({
+      type: "assistant",
+      session_id: "error-session",
+      parent_tool_use_id: null,
+      uuid: id,
+      message: {
+        id,
+        role: "assistant",
+        model: error ? "<synthetic>" : "claude-opus-5-5",
+        content: [{ type: "text", text }],
+        stop_reason: "stop_sequence",
+        usage: { input_tokens: 0, output_tokens: 0 },
+      },
+      ...(error ? { error } : {}),
+    });
+    const messages = (async function* () {
+      if (typeof prompt === "string") throw new Error("Expected streaming input");
+      for await (const _message of prompt) {
+        const turn = turns[index];
+        index += 1;
+        yield {
+          type: "system",
+          subtype: "init",
+          session_id: "error-session",
+          permissionMode: "default",
+          model: "claude-opus-5-5",
+        };
+        if (turn.before) yield assistant(`before-${index}`, turn.before);
+        if (turn.errorReply) yield assistant(`error-${index}`, turn.errorReply, "rate_limit");
+        if (turn.after) yield assistant(`after-${index}`, turn.after);
+        yield {
+          type: "result",
+          subtype: "success",
+          session_id: "error-session",
+          duration_ms: 1,
+          duration_api_ms: 0,
+          is_error: turn.isError,
+          num_turns: 1,
+          result: turn.isError ? (turn.errorReply ?? "") : (turn.after ?? turn.errorReply ?? ""),
+          stop_reason: "stop_sequence",
+          total_cost_usd: turn.usage?.totalCostUsd ?? 0,
+          usage: {
+            input_tokens: turn.usage?.inputTokens ?? 0,
+            output_tokens: turn.usage?.outputTokens ?? 0,
+            cache_read_input_tokens: turn.usage?.cachedInputTokens ?? 0,
+          },
+          modelUsage: {},
+          permission_denials: [],
+          uuid: `result-${index}`,
+        };
+      }
+    })();
+    return Object.assign(messages, {
+      close: () => {
+        void messages.return();
+      },
+      interrupt: async () => undefined,
+      setModel: async () => undefined,
+      setPermissionMode: async () => undefined,
+      supportedModels: async () => [],
+      supportedCommands: async () => [],
+    }) as ReturnType<ClaudeQueryFactory>;
+  };
+}
+
+async function runTurns(turns: ScriptedTurn[]) {
+  const client = new ClaudeAgentClient({
+    logger: createTestLogger(),
+    queryFactory: scriptedQuery(turns),
+    resolveBinary: async () => process.execPath,
+  });
+  const session = await client.createSession({
+    provider: "claude",
+    cwd: process.cwd(),
+  });
+  try {
+    const results = [];
+    for (const [index] of turns.entries()) {
+      results.push(await collectSessionTurnEvents(session, `turn ${index + 1}`));
+    }
+    return results;
+  } finally {
+    await session.close();
+  }
+}
+
+function assistantTexts(events: Awaited<ReturnType<typeof runTurns>>[number]): string[] {
+  return events.flatMap((event) =>
+    event.type === "timeline" && event.item.type === "assistant_message" ? [event.item.text] : [],
+  );
+}
+
+function terminal(events: Awaited<ReturnType<typeof runTurns>>[number]) {
+  return events.find(
+    (event) =>
+      event.type === "turn_completed" ||
+      event.type === "turn_failed" ||
+      event.type === "turn_canceled",
+  );
+}
+
+test("a turn Claude Code ends on an API error fails with the error, shown once", async () => {
+  const [limited, overloaded, next] = await runTurns([
+    { errorReply: LIMIT, isError: true },
+    {
+      before: "Checking the deploy doc.",
+      errorReply: "API Error: 529 Overloaded",
+      isError: true,
+    },
+    { after: "Done.", isError: false },
+  ]);
+
+  expect(terminal(limited)).toMatchObject({
+    type: "turn_failed",
+    error: LIMIT,
+  });
+  expect(assistantTexts(limited)).toEqual([]);
+
+  expect(terminal(overloaded)).toMatchObject({
+    type: "turn_failed",
+    error: "API Error: 529 Overloaded",
+  });
+  expect(assistantTexts(overloaded)).toEqual(["Checking the deploy doc."]);
+
+  // The session keeps working after a failed turn.
+  expect(terminal(next)).toMatchObject({ type: "turn_completed" });
+  expect(assistantTexts(next)).toEqual(["Done."]);
+});
+
+test("a failed turn retains its final token counts and cost", async () => {
+  const usage = {
+    inputTokens: 120,
+    cachedInputTokens: 80,
+    outputTokens: 30,
+    totalCostUsd: 0.012,
+  };
+  const [failed] = await runTurns([
+    { before: "Checking the deploy doc.", errorReply: LIMIT, isError: true, usage },
+  ]);
+
+  expect(failed).toContainEqual(
+    expect.objectContaining({ type: "usage_updated", usage: expect.objectContaining(usage) }),
+  );
+  expect(terminal(failed)).toMatchObject({ type: "turn_failed", error: LIMIT });
+  expect(assistantTexts(failed)).toEqual(["Checking the deploy doc."]);
+});
+
+test("an error reply the turn moves past is still shown", async () => {
+  const [recovered, completed] = await runTurns([
+    {
+      errorReply: "API Error: 529 Overloaded",
+      after: "Recovered.",
+      isError: false,
+    },
+    { errorReply: LIMIT, isError: false },
+  ]);
+
+  expect(terminal(recovered)).toMatchObject({ type: "turn_completed" });
+  expect(assistantTexts(recovered)).toEqual(["API Error: 529 Overloaded", "Recovered."]);
+
+  expect(terminal(completed)).toMatchObject({ type: "turn_completed" });
+  expect(assistantTexts(completed)).toEqual([LIMIT]);
+});

packages/server/src/server/agent/providers/claude/agent.import-titles.test.ts

@@ -1,3 +1,4 @@
+import { constants as bufferConstants } from "node:buffer";
 import * as fs from "node:fs/promises";
 import * as os from "node:os";
 import * as path from "node:path";
@@ -236,4 +237,64 @@ describe("importing a renamed Claude session", () => {
 
     await expect(importSession(sessionId)).rejects.toThrow();
   });
+
+  test("reads the rename from a transcript too large to hold as one string", async () => {
+    const sessionId = "oversized-transcript";
+    const projectDir = claudeProjectDirSync(SESSION_CWD, { configDir });
+    await fs.mkdir(projectDir, { recursive: true });
+    const transcript = path.join(projectDir, `${sessionId}.jsonl`);
+    // A hole stands in for the long session this used to fail on: the file only
+    // has to be longer than a string can be, and the rename sits at its end.
+    await fs.writeFile(transcript, "");
+    await fs.truncate(transcript, bufferConstants.MAX_STRING_LENGTH + 1);
+    await fs.appendFile(
+      transcript,
+      `\n${[
+        userRecord({ sessionId, content: "Trace the slow query" }),
+        { type: "custom-title", customTitle: "Slow query hunt", sessionId },
+      ]
+        .map((record) => JSON.stringify(record))
+        .join("\n")}\n`,
+    );
+
+    const imported = await importSession(sessionId);
+
+    expect(imported.config.title).toBe("Slow query hunt");
+  });
+
+  test("reads the rename from behind more records than one read covers", async () => {
+    const sessionId = "late-records-rename";
+    await writeSession({
+      sessionId,
+      records: [
+        userRecord({ sessionId, content: "Review this project" }),
+        { type: "custom-title", customTitle: "Scrollback review", sessionId },
+        // One record longer than a single read, then enough records to leave the
+        // rename several reads back from the end of the file.
+        userRecord({ sessionId, content: "x".repeat(128 * 1024) }),
+        ...Array.from({ length: 64 }, (_, index) =>
+          userRecord({ sessionId, content: `${"y".repeat(4 * 1024)} ${index}` }),
+        ),
+      ],
+    });
+
+    const imported = await importSession(sessionId);
+
+    expect(imported.config.title).toBe("Scrollback review");
+  });
+
+  test("imports a large record after the last rename without repeatedly copying it", async () => {
+    const sessionId = "large-record-after-rename";
+    await writeSession({
+      sessionId,
+      records: [
+        { type: "custom-title", customTitle: "Large attachment review", sessionId },
+        userRecord({ sessionId, content: "x".repeat(96 * 1024 * 1024) }),
+      ],
+    });
+
+    const imported = await importSession(sessionId);
+
+    expect(imported.config.title).toBe("Large attachment review");
+  });
 });

packages/server/src/server/agent/providers/claude/agent.ts

@@ -2389,6 +2389,12 @@ class ClaudeAgentSession implements AgentSession {
   private mainTurnInFlight = false;
   private foregroundHasVisibleActivity = false;
   private activeTurnHasAssistantText = false;
+  /**
+   * The reply Claude Code writes when a turn stops on an API error ("You've hit your session
+   * limit", "API Error: 529 ..."), held back until the result says whether the turn failed: a
+   * failed turn shows the same text as its error, so showing both would repeat it.
+   */
+  private withheldErrorReply: AgentTimelineItem[] = [];
   private readonly contextUsage: ClaudeContextUsageState;
   private userMessageIds: string[] = [];
   private readonly emittedUserMessageIds = new Set<string>();
@@ -2531,6 +2537,7 @@ class ClaudeAgentSession implements AgentSession {
     this.activeForegroundTurnId = turnId;
     this.foregroundHasVisibleActivity = false;
     this.activeTurnHasAssistantText = false;
+    this.withheldErrorReply = [];
     this.contextUsage.beginTurn();
     this.transitionTurnState("foreground", "foreground turn started");
     this.clearRecentStderr();
@@ -4419,6 +4426,21 @@ class ClaudeAgentSession implements AgentSession {
               }) satisfies AgentStreamEvent,
           );
 
+    if (!readClaudeParentToolUseId(message)) {
+      if (message.type === "assistant" && message.error) {
+        this.withheldErrorReply.push(...assistantTimelineEvents.map((event) => event.item));
+        return messageEvents;
+      }
+      if (
+        message.type === "assistant" ||
+        message.type === "user" ||
+        message.type === "stream_event"
+      ) {
+        const released: AgentStreamEvent[] = [];
+        this.releaseWithheldErrorReply(released);
+        return [...released, ...messageEvents, ...assistantTimelineEvents];
+      }
+    }
     return [...messageEvents, ...assistantTimelineEvents];
   }
 
@@ -4966,6 +4988,23 @@ class ClaudeAgentSession implements AgentSession {
     events: AgentStreamEvent[],
   ): void {
     const usage = this.convertUsage(message);
+    // Claude Code reports a turn that stopped on an API error (a usage limit, an overloaded or
+    // rejected request) as `success` with `is_error`, carrying the error text in `result`.
+    if (message.subtype === "success" && message.is_error) {
+      const withheld = this.withheldErrorReply;
+      this.withheldErrorReply = [];
+      const resultText = typeof message.result === "string" ? message.result.trim() : "";
+      const withheldText = withheld
+        .map((item) => (item.type === "assistant_message" ? item.text : ""))
+        .join("\n")
+        .trim();
+      if (usage) events.push({ type: "usage_updated", provider: "claude", usage });
+      events.push(...this.sidechainTracker.finishAll("failed"));
+      events.push(this.buildTurnFailedEvent(resultText || withheldText || "Claude run failed"));
+      return;
+    }
+    const releasedErrorReply = this.withheldErrorReply.length > 0;
+    this.releaseWithheldErrorReply(events);
     if (message.subtype === "success") {
       events.push(...this.sidechainTracker.finishAll("completed"));
       // Built-in slash commands (e.g. /voice, /usage, "Unknown command: …")
@@ -4975,7 +5014,12 @@ class ClaudeAgentSession implements AgentSession {
       // accounting from provider gateways does not duplicate streamed output.
       const resultText = typeof message.result === "string" ? message.result.trim() : "";
       const outputTokens = message.usage?.output_tokens;
-      if (resultText.length > 0 && outputTokens === 0 && !this.activeTurnHasAssistantText) {
+      if (
+        resultText.length > 0 &&
+        outputTokens === 0 &&
+        !this.activeTurnHasAssistantText &&
+        !releasedErrorReply
+      ) {
         events.push({
           type: "timeline",
           provider: "claude",
@@ -4997,6 +5041,14 @@ class ClaudeAgentSession implements AgentSession {
     events.push(this.buildTurnFailedEvent(errorMessage));
   }
 
+  private releaseWithheldErrorReply(events: AgentStreamEvent[]): void {
+    if (this.withheldErrorReply.length === 0) return;
+    for (const item of this.withheldErrorReply) {
+      events.push({ type: "timeline", item, provider: "claude" });
+    }
+    this.withheldErrorReply = [];
+  }
+
   private createClaudeSessionChangedNotice(
     oldSessionId: string,
     newSessionId: string,
@@ -6853,40 +6905,79 @@ function normalizeClaudeSessionTitle(title: string | null): string | null {
 }
 
 const CLAUDE_CUSTOM_TITLE_TYPE = "custom-title";
+const CLAUDE_CUSTOM_TITLE_NEEDLE = Buffer.from(`"${CLAUDE_CUSTOM_TITLE_TYPE}"`);
+const CLAUDE_TITLE_SCAN_CHUNK_BYTES = 64 * 1024;
+
+function readClaudeCustomTitleFromRecord(record: Buffer): string | null {
+  // The needle also matches a prompt that quotes it, so a record still has to
+  // parse as a `custom-title` entry carrying a usable name. Records without the
+  // needle are never decoded, so a long one costs a byte search and nothing more.
+  if (!record.includes(CLAUDE_CUSTOM_TITLE_NEEDLE)) {
+    return null;
+  }
+  let parsed: unknown;
+  try {
+    parsed = JSON.parse(record.toString("utf8").trim());
+  } catch {
+    return null;
+  }
+  const entry = toObjectRecord(parsed);
+  if (!entry || entry.isSidechain || entry.type !== CLAUDE_CUSTOM_TITLE_TYPE) {
+    return null;
+  }
+  return normalizeClaudeSessionTitle(
+    typeof entry.customTitle === "string" ? entry.customTitle : null,
+  );
+}
 
 /**
  * The `custom-title` record is re-emitted every time the session is saved, so
- * the current name is the last usable one in the file. Searching backwards finds it without
- * walking the transcript, which matters because sessions reach tens of
- * megabytes.
+ * the current name is the last usable one in the file. Reading backwards a chunk
+ * at a time finds it without walking the transcript, which matters because
+ * sessions reach tens of megabytes, and never holds the file as one string, so a
+ * transcript past V8's maximum string length still imports.
  */
-function readLastClaudeCustomTitle(content: string): string | null {
-  const needle = `"${CLAUDE_CUSTOM_TITLE_TYPE}"`;
-  let at = content.lastIndexOf(needle);
-  while (at >= 0) {
-    const lineStart = content.lastIndexOf("\n", at) + 1;
-    const lineEnd = content.indexOf("\n", at);
-    const line = lineEnd === -1 ? content.slice(lineStart) : content.slice(lineStart, lineEnd);
-    let parsed: unknown;
-    try {
-      parsed = JSON.parse(line.trim());
-    } catch {
-      parsed = undefined;
-    }
-    const entry = toObjectRecord(parsed);
-    if (entry && !entry.isSidechain && entry.type === CLAUDE_CUSTOM_TITLE_TYPE) {
-      const title = normalizeClaudeSessionTitle(
-        typeof entry.customTitle === "string" ? entry.customTitle : null,
+async function readLastClaudeCustomTitle(filePath: string): Promise<string | null> {
+  const handle = await fsPromises.open(filePath, "r");
+  try {
+    const stats = await handle.stat();
+    if (!stats.isFile()) {
+      // Opening a directory succeeds on Windows even though reading it does not,
+      // so reject the way reading the transcript as a file would.
+      throw Object.assign(
+        new Error(`EISDIR: illegal operation on a directory, read '${filePath}'`),
+        { code: "EISDIR", path: filePath },
       );
-      if (title) {
-        return title;
-      }
     }
-    // The needle also matches a prompt that quotes it, and a record can carry no
-    // usable name, so keep looking backwards for one that does.
-    at = at <= 0 ? -1 : content.lastIndexOf(needle, at - 1);
+    let end = stats.size;
+    // Retain unfinished record pieces in reverse file order. Assemble each
+    // complete record once, so a large tool/image record costs linear work.
+    let pieces: Buffer[] = [];
+    while (end > 0) {
+      const length = Math.min(CLAUDE_TITLE_SCAN_CHUNK_BYTES, end);
+      const chunk = Buffer.alloc(length);
+      await handle.read(chunk, 0, length, end - length);
+      let recordEnd = chunk.length;
+      for (
+        let at = chunk.lastIndexOf(10);
+        at >= 0;
+        at = at === 0 ? -1 : chunk.lastIndexOf(10, at - 1)
+      ) {
+        pieces.push(chunk.subarray(at + 1, recordEnd));
+        const record = Buffer.concat(pieces.toReversed());
+        const title = readClaudeCustomTitleFromRecord(record);
+        if (title) return title;
+        pieces = [];
+        recordEnd = at;
+      }
+      if (recordEnd > 0) pieces.push(chunk.subarray(0, recordEnd));
+      end -= length;
+    }
+    // The first record in the file has no newline in front of it.
+    return readClaudeCustomTitleFromRecord(Buffer.concat(pieces.toReversed()));
+  } finally {
+    await handle.close();
   }
-  return null;
 }
 
 function isErrnoException(error: unknown): error is NodeJS.ErrnoException {
@@ -6898,9 +6989,8 @@ async function readClaudeRenamedSessionTitle(input: {
   sessionId: string;
   configDir: string;
 }): Promise<string | null> {
-  let content: string;
   try {
-    content = await fsPromises.readFile(await claudeTranscriptPath(input), "utf8");
+    return await readLastClaudeCustomTitle(await claudeTranscriptPath(input));
   } catch (error) {
     // A session with no transcript on disk has no rename to carry over. Every
     // other read failure is a real fault and stays explicit.
@@ -6909,7 +6999,6 @@ async function readClaudeRenamedSessionTitle(input: {
     }
     throw error;
   }
-  return readLastClaudeCustomTitle(content);
 }
 
 function normalizeImportablePromptPreview(text: string): string | null {

packages/server/src/server/daemon-e2e/file-download.e2e.test.ts

@@ -102,53 +102,52 @@ describe("daemon E2E", () => {
       },
     );
 
-    test.each([
-      { fileName: "download.txt", disposition: 'attachment; filename="download.txt"' },
-      {
-        fileName: "café.txt",
-        disposition: "attachment; filename=\"caf?.txt\"; filename*=UTF-8''caf%C3%A9.txt",
-      },
-      {
-        fileName: "中文报告 (最终版).txt",
-        disposition:
-          "attachment; filename=\"???? (???).txt\"; filename*=UTF-8''%E4%B8%AD%E6%96%87%E6%8A%A5%E5%91%8A%20%28%E6%9C%80%E7%BB%88%E7%89%88%29.txt",
-      },
-      {
-        fileName: "報告書.md",
-        disposition:
-          "attachment; filename=\"???.md\"; filename*=UTF-8''%E5%A0%B1%E5%91%8A%E6%9B%B8.md",
-      },
-      {
-        fileName: "보고서.txt",
-        disposition:
-          "attachment; filename=\"???.txt\"; filename*=UTF-8''%EB%B3%B4%EA%B3%A0%EC%84%9C.txt",
-      },
-      {
-        fileName: "report-📄.txt",
-        disposition:
-          "attachment; filename=\"report-??.txt\"; filename*=UTF-8''report-%F0%9F%93%84.txt",
-      },
-    ])(
-      "issues token over WS and downloads $fileName via HTTP",
-      async ({ fileName, disposition }) => {
-        const cwd = tmpCwd();
-        try {
+    test("downloads ASCII and Unicode filenames through one workspace", async () => {
+      const cwd = tmpCwd();
+      try {
+        const agent = await ctx.client.createAgent({
+          provider: "codex",
+          model: CODEX_TEST_MODEL,
+          thinkingOptionId: CODEX_TEST_THINKING_OPTION_ID,
+          cwd,
+          title: "Download Token Test Agent",
+        });
+
+        expect(agent.id).toMatch(
+          /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/,
+        );
+
+        for (const { fileName, disposition } of [
+          { fileName: "download.txt", disposition: 'attachment; filename="download.txt"' },
+          {
+            fileName: "café.txt",
+            disposition: "attachment; filename=\"caf?.txt\"; filename*=UTF-8''caf%C3%A9.txt",
+          },
+          {
+            fileName: "中文报告 (最终版).txt",
+            disposition:
+              "attachment; filename=\"???? (???).txt\"; filename*=UTF-8''%E4%B8%AD%E6%96%87%E6%8A%A5%E5%91%8A%20%28%E6%9C%80%E7%BB%88%E7%89%88%29.txt",
+          },
+          {
+            fileName: "報告書.md",
+            disposition:
+              "attachment; filename=\"???.md\"; filename*=UTF-8''%E5%A0%B1%E5%91%8A%E6%9B%B8.md",
+          },
+          {
+            fileName: "보고서.txt",
+            disposition:
+              "attachment; filename=\"???.txt\"; filename*=UTF-8''%EB%B3%B4%EA%B3%A0%EC%84%9C.txt",
+          },
+          {
+            fileName: "report-📄.txt",
+            disposition:
+              "attachment; filename=\"report-??.txt\"; filename*=UTF-8''report-%F0%9F%93%84.txt",
+          },
+        ]) {
           const filePath = path.join(cwd, fileName);
-          const fileContents = "download test payload";
+          const fileContents = `download test payload: ${fileName}`;
           writeFileSync(filePath, fileContents, "utf-8");
 
-          const agent = await ctx.client.createAgent({
-            provider: "codex",
-            model: CODEX_TEST_MODEL,
-            thinkingOptionId: CODEX_TEST_THINKING_OPTION_ID,
-            cwd,
-            title: "Download Token Test Agent",
-          });
-
-          expect(agent.id).toMatch(
-            /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/,
-          );
-
           const tokenResponse = await ctx.client.requestDownloadToken(cwd, fileName);
 
           expect(tokenResponse.error).toBeNull();
@@ -167,12 +166,11 @@ describe("daemon E2E", () => {
 
           const body = await response.text();
           expect(body).toBe(fileContents);
-        } finally {
-          rmSync(cwd, { recursive: true, force: true });
         }
-      },
-      60000,
-    );
+      } finally {
+        rmSync(cwd, { recursive: true, force: true });
+      }
+    }, 60000);
 
     test("rejects invalid token", async () => {
       const response = await fetch(