fix(server): retain restart-safe images with async processing

Integrate current main while preserving stable attachment storage, async materialization, bounded decoding and atomic publication. Adapt the restart regression and private-storage tests to the asynchronous API and isolate all materialization tests from the real home.

.oxlintrc.json

@@ -85,6 +85,151 @@
     "max-nested-callbacks": ["error", { "max": 3 }]
   },
   "overrides": [
+    // Exceptions name individual APIs in individual modules; new APIs still fail in these files.
+    // TODO entries are runtime debt, not startup exemptions. Do not add directory-wide exceptions.
+    {
+      "files": ["packages/server/src/**/*.{ts,tsx,mts,cts,js,jsx,mjs,cjs}"],
+      "rules": {
+        "paseo/no-sync-io": [
+          "error",
+          {
+            "allow": {
+              // TODO: literal executableExists is a synchronous public capability; move its callers and Windows existence predicates to async together.
+              "executable-resolution/executable-resolution.ts": ["existsSync"],
+              // TODO: winget enumeration shares synchronous existence predicates with literal lookup; convert the executable-resolution boundary together.
+              "executable-resolution/windows.ts": ["readdirSync"],
+              // TODO: live file-change classification is a synchronous event mapper; move the probe to async event ingestion.
+              "server/agent/providers/claude/agent.ts": ["existsSync"],
+              // TODO: new-session construction still resolves its project directory synchronously; move preparation before construction.
+              "server/agent/providers/claude/project-dir.ts": ["realpathSync"],
+              // TODO: live subagent output is read by a synchronous event mapper; add bounded async loading at ingestion.
+              "server/agent/providers/claude/subagents/workflow-output.ts": [
+                "closeSync",
+                "openSync",
+                "readSync"
+              ],
+              // TODO: diagnostics probes provider-owned auth/session storage; convert alongside provider discovery and readiness.
+              "server/agent/providers/omp/agent.ts": ["existsSync"],
+              // TODO: synchronous provider configuration discovery; move discovery into async launch preparation.
+              "server/agent/providers/omp/provider-config.ts": ["existsSync"],
+              // TODO: synchronous session-root selection is shared by descriptor builders; migrate callers with explicit readiness.
+              "server/agent/providers/omp/session-descriptor.ts": ["existsSync"],
+              // TODO: launch directory creation shares the server generation/start state machine; audit concurrent rotation before adding an await.
+              "server/agent/providers/opencode/server-manager.ts": ["mkdirSync"],
+              // TODO: launch preparation owns MCP config merge, extension generation and synchronous cleanup; migrate lifecycle and diagnostics together.
+              "server/agent/providers/pi/agent.ts": [
+                "existsSync",
+                "mkdtempSync",
+                "readFileSync",
+                "rmSync",
+                "writeFileSync"
+              ],
+              // Provider child process: Pi loads this extension outside the daemon; it reads child-agent status there.
+              "server/agent/providers/pi/extensions/pi-subagents/index.ts": ["readFileSync"],
+              // Startup/shutdown only: remove stale Unix listening sockets before bind and during disposal.
+              "server/bootstrap.ts": ["existsSync", "unlinkSync"],
+              // Startup configuration resolution: detect the bundled app distribution before the daemon listens.
+              "server/config.ts": ["existsSync"],
+              // Startup identity: load or create the daemon keypair before accepting connections.
+              "server/daemon-keypair.ts": ["existsSync", "readFileSync"],
+              // Fatal exit diagnostics: synchronously flush the exit reason when the worker is about to terminate.
+              "server/daemon-worker.ts": ["appendFileSync", "mkdirSync"],
+              // Startup host identity: memoized scutil lookup is warmed before listening; later callers use the cache.
+              "server/host-name.ts": ["execFileSync"],
+              // TODO: relationship persistence is atomic with enrollment/revocation state transitions; serialize those transitions before async writes.
+              "server/hub/relationship-controller.ts": [
+                "existsSync",
+                "readFileSync",
+                "renameSync",
+                "rmSync"
+              ],
+              // Local client bootstrap: reads the local credential and pid lock to select/authenticate a daemon connection.
+              "server/local-credential.ts": ["readFileSync"],
+              // Startup logger construction: create the log directory before opening the logging destination.
+              "server/logger.ts": ["mkdirSync"],
+              // TODO: runtime skill commands resolve their bundled source through a synchronous targets capability; migrate the capability and controller together.
+              "server/orchestration-skills/internal/paths.ts": ["existsSync"],
+              // Module initialization: the package version is resolved once and cached at import.
+              "server/package-version.ts": ["existsSync", "readFileSync"],
+              // Startup config and exported synchronous configuration API; runtime DaemonConfigStore uses the async load/save capabilities.
+              "server/persisted-config.ts": ["existsSync", "readFileSync"],
+              // Startup pid identity: read and memoize the Linux boot id for the daemon lock.
+              "server/pid-lock.ts": ["readFileSync"],
+              // Startup builtin loader construction: select the bundled plugin root before loading plugins.
+              "server/plugins/builtin/index.ts": ["existsSync"],
+              // Build child process: plugin graph traversal and esbuild preparation run in the isolated compiler process.
+              "server/plugins/compiler-build.ts": ["existsSync", "readFileSync", "realpathSync"],
+              // Build child process: select the esbuild binary for the isolated plugin compiler.
+              "server/plugins/compiler-esbuild.ts": ["existsSync"],
+              // Build child process: TypeScript resolution and source reads run in the isolated plugin compiler.
+              "server/plugins/compiler-imports.ts": ["readFileSync", "realpathSync"],
+              // TODO: plugin install/update/remove commits sources.json synchronously; preserve record/write ordering with an async mutation queue.
+              "server/plugins/managed-source.ts": ["existsSync", "readFileSync"],
+              // TODO: shared synchronous persistence supports startup identity plus Hub/plugin/push runtime writers; migrate those owners before removing these exports.
+              "server/private-files.ts": [
+                "chmodSync",
+                "mkdirSync",
+                "realpathSync",
+                "renameSync",
+                "rmSync",
+                "writeFileSync"
+              ],
+              // TODO: constructor load plus runtime renew/revoke/prune use synchronous persistence; introduce ordered async mutations and readiness.
+              "server/push/token-store.ts": ["existsSync", "readFileSync"],
+              // Startup identity: load or create the server id before accepting connections.
+              "server/server-id.ts": ["existsSync", "readFileSync"],
+              // Listener lifecycle only: unlink the Unix socket before binding or after stopping the proxy.
+              "server/service-proxy.ts": ["existsSync", "unlinkSync"],
+              // TODO: self-update origin validation exposes synchronous package-root and realpath checks; migrate validation and its runtime interface together.
+              "server/session/daemon/install-origin.ts": ["existsSync", "readFileSync"],
+              // TODO: npm self-update inspection probes the reported install path; move the probe into bounded async installation inspection.
+              "server/session/daemon/npm-global-cli.ts": ["lstatSync"],
+              // Speech child process: model-file validation runs in the worker-backed local speech provider.
+              "server/speech/providers/local/sherpa/sherpa-offline-recognizer.ts": ["existsSync"],
+              // Speech child process: native addon discovery and patchelf run outside the daemon.
+              "server/speech/providers/local/sherpa/sherpa-onnx-node-loader.ts": [
+                "existsSync",
+                "spawnSync"
+              ],
+              // Speech child process: model-file validation runs in the worker-backed local speech provider.
+              "server/speech/providers/local/sherpa/sherpa-tts.ts": ["existsSync"],
+              // TODO: static request selection and index injection need bounded async serving with response/error ownership; keep this as a separate request-path conversion.
+              "server/web-ui.ts": ["readFileSync", "statSync"],
+              // Startup registry hydration: check persisted workspace directories before the runtime reconciliation service starts.
+              "server/workspace-registry-bootstrap.ts": ["statSync"],
+              // Terminal child process: hook config installation/removal is owned by terminal creation and teardown in the worker.
+              "terminal/agent-hooks/agent-hook-installer.ts": [
+                "existsSync",
+                "readFileSync",
+                "rmSync"
+              ],
+              // Node loader thread: TypeScript terminal-worker resolution runs in the loader, outside the daemon event loop.
+              "terminal/terminal-ts-loader.mjs": ["existsSync"],
+              // Terminal child process: executable preparation and shell integration run in the worker-backed terminal manager.
+              "terminal/terminal.ts": [
+                "accessSync",
+                "chmodSync",
+                "existsSync",
+                "mkdirSync",
+                "readFileSync",
+                "statSync"
+              ],
+              // TODO: legacy realpath helpers still serve install-origin validation and other synchronous consumers; migrate remaining callers before removing them.
+              "utils/path.ts": ["realpathSync"]
+            }
+          }
+        ]
+      }
+    },
+    {
+      "files": [
+        "packages/server/src/**/*.{test,spec,fixture}.{ts,tsx,mts,cts,js,jsx,mjs,cjs}",
+        "packages/server/src/**/test-utils/**",
+        "packages/server/src/server/daemon-e2e/**",
+        "packages/server/src/server/agent/providers/pi/extensions/*-test.ts"
+      ],
+      "rules": { "paseo/no-sync-io": "off" }
+    },
     {
       "files": [
         "plugins/*-provider/server/**/*.ts",

docs/development.md

@@ -273,6 +273,26 @@ Playwright dispatch lateness. Set `PASEO_PROFILE_TYPING_KEYS`, `PASEO_PROFILE_TY
 `PASEO_PROFILE_CPU_PATH` and `PASEO_PROFILE_TRACE_PATH` captures run separately after the latency
 measurements so profiling overhead does not contaminate them.
 
+For diff layout, two benchmarks share one corpus
+(`packages/app/src/git/diff-document/benchmark-corpus.ts`: a real source file, a changelog with
+600-character lines, generated code with ligature punctuation, and JSON). The node bench runs the
+shared document model with the web and native measurers replaced by counters, so it reports how
+many strings each backend would have to shape, which is the cost that survives the move to canvas
+or Skia:
+
+```bash
+cd packages/app && npx vitest bench --project unit src/git/diff-document/model.bench.ts
+```
+
+The browser benchmark opens the same corpus as a working diff, toggles line wrap from the toolbar,
+and reports pointer-down to painted latency, the longest main-thread task, and the `DiffDocument`
+React commit time for cold and warm toggles, then scroll frame times in both modes:
+
+```bash
+cd packages/app && PASEO_DIFF_PERF_E2E=1 npx playwright test --project=browser \
+  e2e/browser/diff-performance.spec.ts -g "toggling line wrap"
+```
+
 Set `PASEO_PROFILE_TYPING_SCENARIO=height-growth` to alternate `Shift+Enter` and printable input.
 That report includes input and composer height changes plus React work grouped into composer,
 stream, and ancestor/root scopes. Ancestor/root timings include descendant work because the Profiler
@@ -542,6 +562,39 @@ patch every build the consumers use: Metro resolves the `react-native` field of
 (`src/*.ts` for `react-native-svg`), while Node and Vitest resolve `main`/`module`
 (`lib/commonjs`, `lib/module`). Patching only `lib/` leaves the app bundle unfixed.
 
+## Dependency overrides and workspace tooling
+
+Root `package.json` `overrides` pin one Expo SDK across the tree (`expo`, `expo-router`,
+`react-native`, …). npm does not apply those overrides to packages it places under a
+workspace's own `node_modules`. When `expo-module-scripts` was declared in
+`packages/expo-two-way-audio`, npm nested it there and its `jest-expo` peer `expo@*` resolved to
+a second, newer Expo SDK and React Native: 200+ duplicate packages nothing imported (#7730).
+Declare tooling that peer-depends on `expo` or `react-native` in the root `devDependencies`,
+where the overrides apply; workspace scripts still find the binary through the root
+`node_modules/.bin`.
+
+## Dependency signature audit
+
+The `quality` CI job runs `npm audit signatures`. It verifies every lockfile package's registry
+signature and, for packages published with provenance, fetches
+`/-/npm/v1/attestations/<name>@<version>` from the registry. Cloudflare caches that document
+for a year. An edge that cached it in the seconds before the registry attached the publish
+attestation keeps serving a document with only the provenance bundle, and npm fails with:
+
+```
+npm error code EMISSINGSIGNATUREKEY
+npm error <name>@<version> has attestations but no corresponding public key(s) can be found
+```
+
+The same package's registry signature verified a moment earlier with the same keys, so the
+key list is intact. The failure names one package, repeats only for that package, and depends
+on the Azure region the runner landed in, because each region maps to one Cloudflare colo. A
+rerun passes only by landing elsewhere.
+
+To confirm, fetch the URL from several runners and compare `content-length`, the `cf-ray` colo
+suffix, and the number of `attestations` entries (#7730 has the probe). To fix, remove or
+replace that version in the lockfile and report the URL to npm so they purge it.
+
 ## ACP provider catalog versions
 
 The in-app ACP provider catalog pins package-runner entries (`npx`, `npm exec`,

docs/plugins.md

@@ -430,8 +430,15 @@ The [public reference](../public-docs/plugins/reference.md#icons) owns the autho
 
 Server entries register lifecycle observers with `server.on()` and request transforms with
 `server.before()`. The [public reference](../public-docs/plugins/reference.md#lifecycle-hooks)
-owns callback shapes, ordering, and failure behavior. `plugin-examples/lifecycle-logger` registers all
+owns callback shapes, ordering, and failure behavior. `agent.create` edits the agent's saved
+configuration; `agent.session_open` contributes launch-only `env`, `tools`, and `mcpServers`,
+re-derived on each open and following the plugin's lifecycle. See
+[Inject MCP servers](../public-docs/plugins/reference.md#inject-mcp-servers) for choosing the hook.
+`plugin-examples/lifecycle-logger` registers all
 eleven hooks; `plugin-examples/lifecycle-actions` demonstrates common automation callbacks.
+Session-open hooks also [attach tools to individual agents](../public-docs/plugins/reference.md#attach-tools-to-agents),
+as shown in `plugin-examples/agent-tools`. The agent manager stamps their metadata per session;
+executable definitions stay in the plugin process.
 
 Emit from the operation owner, not a client subscription. Provider history replay must not trigger
 live hooks. Observers must not be awaited inside agent mutations: a callback can send a prompt or

docs/protocol-compatibility.md

@@ -2,7 +2,7 @@
 
 The app and the daemon are separate products that ship separately. A user updates the app from an app store or a desktop auto-update; they update the daemon when they feel like it. Every combination happens in the wild: new app against an old daemon, old app against a new daemon, and both sides months apart.
 
-In development both sides are always the same version, which is why this is the constraint contributors miss most often.
+Development can have the same version drift: an app reload picks up new code while a long-running daemon keeps its loaded version. Check the connected daemon version when diagnosing behavior that crosses this boundary.
 
 Two contracts follow from it.
 
@@ -38,7 +38,7 @@ The app checks for the capability and either runs the feature or tells the user
 - **No defensive branches spread through the feature.** Detection happens in one place, and everything downstream reads a clean shape.
 - Capability flags live in `features` on the `server_info` message (`packages/protocol/src/messages.ts`, the `server_info` schema).
 
-Existing functionality keeps working across versions because of the protocol contract. Gating a new feature never substitutes for that.
+Existing functionality keeps working across versions. Never gate an established request on a new enhancement: negotiate the optional enhancement at the client boundary and preserve the existing request for older hosts. Whole-turn pagination can require a capability; reading conversation history cannot.
 
 ## Client capability ownership
 

docs/timeline-sync.md

@@ -13,7 +13,7 @@ and rebuilds the projection when an agent resumes.
 The invariants are:
 
 > A continuously subscribed client applies every committed row in order. Opening or resuming an
-> agent establishes the daemon's current tail in one bounded request, with older history reachable
+> agent establishes the daemon's current tail in one complete-turn request, with older history reachable
 > through backward pagination.
 
 Tool output is bounded before it enters either delivery path. Canonical shell tool output is sliced
@@ -44,7 +44,21 @@ recovery is complete only when `hasNewer: false`.
 
 Initialization timeouts guard lack of catch-up progress, not the full multi-page sync. A successful page that queues the next `after` page refreshes the watchdog.
 
-Opening or resuming an agent fetches one bounded latest tail page. Older history remains
+Opening or resuming an agent fetches the latest available turns with a soft target of 40
+projected items. Backward pages and prompt-jump windows also include whole turns, including
+all currently available rows of an active run. There is no per-turn cap: a large run can
+exceed the target. Local history mounting uses the same boundaries so revealing older rows
+does not change the collapse state of a turn already displayed.
+
+`wholeTurns` is a preference negotiated once at the client fetch boundary. Hosts advertising
+`features.wholeTurnTimeline` receive it; other hosts receive the existing item-based request.
+Reading history remains available on older hosts, whose pages can still split turns. Forward
+catch-up stays incremental, but its reset snapshot honors a supported whole-turn request.
+Source coverage still includes interleaved tool updates.
+
+Canonical IDs define runs. With missing IDs, human prompts, heartbeats and typed received
+agent messages each start a fallback turn. This deterministic fallback is shared by paging
+and presentation; it cannot recover historical batching or steering. Older history remains
 user-driven by scrolling upward.
 
 A failed catch-up or subscription reconcile retries on its own, doubling from 1s to a 30s ceiling.
@@ -149,12 +163,13 @@ range describes those exact items: `startSeq` drives older pagination and `endSe
 catch-up. The owner requests `after endSeq`, and requests `before startSeq` when the user loads older
 history. Code outside the owner does not distinguish cached and network timelines.
 
-The first resume request is bounded. If it reports more newer history, fetch one latest bounded tail
+The first resume request is bounded. If it reports more newer history, fetch one latest complete-turn tail
 instead of replaying every missed page. Live gap recovery still pages forward until current.
 
-If the canonical window exceeds the cache item limit, contains a discontiguous retained range, has a
+If the canonical window exceeds the cache item target, contains a discontiguous retained range, has a
 live head, or includes presentation data the cache cannot encode losslessly, persistence drops the
-range and keeps a display-only tail. Never slice items while retaining the pre-slice range; that
+range and keeps a display-only tail of complete available turns. The item target is soft;
+the byte budget still evicts entire cache rows. Never slice items while retaining the pre-slice range; that
 falsely certifies discarded source rows. A display-only row paints without granting synchronization
 authority, so the owner uses the ordinary bounded `tail` bootstrap.
 
@@ -238,11 +253,11 @@ foreground control ownership remains a separate daemon concern. Cancellation req
 with that record rather than in a React component, so an old request cannot clear a newer one. Submissions
 remain a separate pre-turn registry and retire on canonical acknowledgement.
 
-Canonical turns and visible responses are different boundaries. Agent-originated prompts and lifecycle
-notifications project into tool rows, so they do not create a human-message boundary. Legacy system
-prompts, including schedule injections, remain hidden. One visible response can span several canonical
-turns; layout and copy group that response together while lifecycle, timing, tool sequences, and exact
-fork positions retain the canonical `turnId` boundaries.
+Every canonical run owns a visible turn, including heartbeats and agent notifications.
+Notifications delivered during a run stay inside it; batched notifications share the run
+that starts or accepts them. Received messages retain sender attribution, while lifecycle
+notifications remain visible events. Collapse, timing and locally mounted history share
+these boundaries.
 
 Agent-message XML belongs to the daemon's `agent/agent-messages` boundary. Prompt delivery encodes
 provenance; acceptance, provider echoes, import, and replay share its projection. The delivery ID is

nix/npm-deps.hash

@@ -1 +1 @@
-sha256-eNiKmiZ3XXZMRZRSoGxUbMn2RtY6AX079vUatBYM+qE=
+sha256-dk7kJUdmQBF8L8Vkj6Ryza3n4/S+YqgxWY3R59Dc3mY=

package.json

@@ -131,6 +131,7 @@
     "concurrently": "^9.2.1",
     "cross-env": "^10.1.0",
     "electron": "44.2.0",
+    "expo-module-scripts": "^5.0.8",
     "get-port-cli": "^3.0.0",
     "js-yaml": "^4.1.1",
     "knip": "^5.82.1",

packages/app/e2e/browser/agent-message-submission.spec.ts

@@ -53,6 +53,7 @@ import {
 import { expectInFlightForkAvailable } from "../support/helpers/assistant-fork";
 import {
   scrollTimelineToNewestLoadedEdge,
+  userScrollsTimelineToHistoryStart,
   scrollTimelineUntilOlderHistoryIsReachable,
 } from "../support/helpers/timeline-pagination";
 import {
@@ -986,7 +987,7 @@ test.describe("Agent message submission", () => {
     }
   });
 
-  test("keeps one prompt when its provider echo crosses the bounded tail", async ({
+  test("keeps one prompt when a delayed provider echo belongs to a large whole turn", async ({
     page,
   }, testInfo) => {
     const workspace = await seedWorkspace({
@@ -1003,8 +1004,10 @@ test.describe("Agent message submission", () => {
       await expectVisibleAgentSurfacesIdle(page);
       await page.reload();
 
-      await expect(submittedPrompt).toHaveCount(0);
-      await scrollTimelineUntilOlderHistoryIsReachable(page, prompt);
+      // The complete turn arrives on reload; scrolling mounts its oldest rows
+      // without requiring another page or an increase in total content height.
+      await userScrollsTimelineToHistoryStart(page);
+      await expect(submittedPrompt).toBeVisible();
       await expect(submittedPrompt).toHaveCount(1);
       await expect(submittedPrompt).toHaveAttribute("aria-busy", "false");
     } finally {

packages/app/e2e/browser/diff-performance.spec.ts

@@ -1,6 +1,7 @@
 import { writeFile } from "node:fs/promises";
 import path from "node:path";
 import type { CDPSession, Locator, Page, TestInfo } from "@playwright/test";
+import { pullRequestCorpus } from "../../src/git/diff-document/benchmark-corpus";
 import { buildHostWorkspaceRoute } from "../../src/utils/host-routes";
 import { test, expect } from "../support/fixtures";
 import { getServerId } from "../support/helpers/server-id";
@@ -296,8 +297,187 @@ diffPerfDescribe("Diff canvas performance", () => {
       await repo.cleanup().catch(() => undefined);
     }
   });
+  test("toggling line wrap on a pull-request-sized diff", async ({ page }, testInfo) => {
+    test.setTimeout(300_000);
+    const corpus = await createPullRequestCorpusRepository();
+    const client = await connectSeedClient();
+
+    try {
+      const created = await client.createWorkspace({
+        source: { kind: "directory", path: corpus.repo.path },
+      });
+      if (!created.workspace) {
+        throw new Error(created.error ?? "Failed to create wrap performance workspace");
+      }
+
+      await configureUnwrappedUnifiedDiff(page);
+      await instrumentDiffLatency(page);
+      await page.setViewportSize({ width: 1400, height: 900 });
+      await page.goto(buildHostWorkspaceRoute(getServerId(), created.workspace.id));
+      await waitForWorkspaceTabsVisible(page);
+      const openStartedAt = performance.now();
+      await openChangesPanel(page, 90_000);
+      await expect(page.getByTestId("git-diff-canvas")).toBeVisible({ timeout: 30_000 });
+      const open = {
+        readyMs: Math.round(performance.now() - openStartedAt),
+        ...(await readDiffDocumentRenders(page)),
+      };
+
+      const toggles: WrapToggleMeasurement[] = [];
+      for (const name of [
+        "wrap on (cold)",
+        "wrap off (cold)",
+        "wrap on (warm)",
+        "wrap off (warm)",
+      ]) {
+        toggles.push(await measureWrapToggle(page, name));
+      }
+      const unwrappedScroll = await continuouslyScrollCanvas(page);
+      toggles.push(await measureWrapToggle(page, "wrap on (warm, scrolled)"));
+      const wrappedScroll = await continuouslyScrollCanvas(page);
+
+      const report = {
+        scenario: "wrap-toggle",
+        sourceFiles: corpus.fileCount,
+        sourceLines: corpus.lineCount,
+        open,
+        toggles,
+        scroll: {
+          unwrapped: summarizeScroll(unwrappedScroll),
+          wrapped: summarizeScroll(wrappedScroll),
+        },
+      };
+      await attachPerformanceReport(testInfo, report);
+      console.log(`[perf] Wrap toggle: ${JSON.stringify(report)}`);
+
+      const [wrapOn, wrapOff] = toggles;
+      expect(wrapOn!.scrollHeightAfter).toBeGreaterThan(wrapOn!.scrollHeightBefore);
+      expect(wrapOff!.scrollHeightAfter).toBe(wrapOn!.scrollHeightBefore);
+    } finally {
+      await client.close().catch(() => undefined);
+      await corpus.repo.cleanup().catch(() => undefined);
+    }
+  });
 });
 
+interface WrapToggleMeasurement {
+  name: string;
+  /** Pointer down on the toolbar button to two painted frames after the document resized. */
+  latencyMs: number;
+  scrollHeightBefore: number;
+  scrollHeightAfter: number;
+  longestTaskMs: number;
+  longTaskTotalMs: number;
+  diffDocumentCommits: number;
+  diffDocumentRenderMs: number;
+}
+
+interface LongTask {
+  startTime: number;
+  duration: number;
+}
+
+interface DiffLatencyScope {
+  __PASEO_RENDER_PROFILE_ENABLED__?: boolean;
+  __PASEO_RENDER_PROFILE__?: Array<{ id: string; actualDuration: number }>;
+  __PASEO_RESET_RENDER_PROFILE__?: () => void;
+  __PASEO_LONG_TASKS__?: LongTask[];
+  __PASEO_WRAP_TOGGLE_AT__?: number;
+}
+
+async function createPullRequestCorpusRepository() {
+  const files = pullRequestCorpus();
+  const repo = await createTempGitRepo("diff-wrap-perf-", {
+    files: files.map((file) => ({ path: file.path, content: "baseline\n" })),
+  });
+  for (const file of files) {
+    await writeFile(path.join(repo.path, file.path), `${file.lines.join("\n")}\n`);
+  }
+  return {
+    repo,
+    fileCount: files.length,
+    lineCount: files.reduce((count, file) => count + file.lines.length, 0),
+  };
+}
+
+async function instrumentDiffLatency(page: Page): Promise<void> {
+  await page.addInitScript(() => {
+    const scope = globalThis as typeof globalThis & DiffLatencyScope;
+    scope.__PASEO_RENDER_PROFILE_ENABLED__ = true;
+    scope.__PASEO_LONG_TASKS__ = [];
+    new PerformanceObserver((list) => {
+      for (const entry of list.getEntries()) {
+        scope.__PASEO_LONG_TASKS__?.push({ startTime: entry.startTime, duration: entry.duration });
+      }
+    }).observe({ type: "longtask", buffered: true });
+  });
+}
+
+async function readDiffDocumentRenders(
+  page: Page,
+): Promise<{ diffDocumentCommits: number; diffDocumentRenderMs: number }> {
+  return page.evaluate(() => {
+    const scope = globalThis as typeof globalThis & DiffLatencyScope;
+    const samples = (scope.__PASEO_RENDER_PROFILE__ ?? []).filter(
+      (sample) => sample.id === "DiffDocument",
+    );
+    return {
+      diffDocumentCommits: samples.length,
+      diffDocumentRenderMs: Math.round(
+        samples.reduce((total, sample) => total + sample.actualDuration, 0),
+      ),
+    };
+  });
+}
+
+async function measureWrapToggle(page: Page, name: string): Promise<WrapToggleMeasurement> {
+  const scroll = page.getByTestId("git-diff-scroll");
+  const scrollHeightBefore = await scroll.evaluate((element) => element.scrollHeight);
+  await page.evaluate(() => {
+    const scope = globalThis as typeof globalThis & DiffLatencyScope;
+    scope.__PASEO_RESET_RENDER_PROFILE__?.();
+    scope.__PASEO_LONG_TASKS__ = [];
+    scope.__PASEO_WRAP_TOGGLE_AT__ = undefined;
+    document.addEventListener(
+      "pointerdown",
+      () => {
+        scope.__PASEO_WRAP_TOGGLE_AT__ = performance.now();
+      },
+      { capture: true, once: true },
+    );
+  });
+  await page.getByTestId("changes-toggle-wrap-lines").click();
+  const measured = await scroll.evaluate(async (element, before) => {
+    const scope = globalThis as typeof globalThis & DiffLatencyScope;
+    const deadline = performance.now() + 240_000;
+    while (element.scrollHeight === before && performance.now() < deadline) {
+      await new Promise((resolve) => setTimeout(resolve, 5));
+    }
+    await new Promise<void>((resolve) =>
+      requestAnimationFrame(() => requestAnimationFrame(() => resolve())),
+    );
+    const doneAt = performance.now();
+    // Long task entries are delivered after the task ends; give the observer a turn.
+    await new Promise((resolve) => setTimeout(resolve, 50));
+    const startedAt = scope.__PASEO_WRAP_TOGGLE_AT__ ?? doneAt;
+    const longTasks = (scope.__PASEO_LONG_TASKS__ ?? []).filter(
+      (task) => task.startTime + task.duration >= startedAt && task.startTime <= doneAt,
+    );
+    return {
+      latencyMs: Math.round(doneAt - startedAt),
+      scrollHeightAfter: element.scrollHeight,
+      longestTaskMs: Math.round(Math.max(0, ...longTasks.map((task) => task.duration))),
+      longTaskTotalMs: Math.round(longTasks.reduce((total, task) => total + task.duration, 0)),
+    };
+  }, scrollHeightBefore);
+  return { name, scrollHeightBefore, ...measured, ...(await readDiffDocumentRenders(page)) };
+}
+
+function summarizeScroll(report: Awaited<ReturnType<typeof continuouslyScrollCanvas>>) {
+  const { frameSignatures: _frameSignatures, ...summary } = report;
+  return summary;
+}
+
 async function measureAdditionalPerformanceScenario(
   page: Page,
   cdp: CDPSession,

packages/app/e2e/browser/owned-subscriptions-old-daemon.spec.ts

@@ -1,5 +1,4 @@
 import { randomUUID } from "node:crypto";
-import { submitMessage, expectComposerEditable } from "../support/helpers/composer";
 import {
   focusTerminalSurface,
   typeInTerminal,
@@ -12,13 +11,11 @@ import { startIsolatedHostDaemon } from "../support/helpers/isolated-host-daemon
 import type { MockAgentWorkspace } from "../support/helpers/mock-agent";
 import { seedWorkspace } from "../support/helpers/seed-client";
 import {
-  expectTimelinePromptVisible,
-  holdOlderHistoryPages,
   openAgentTimeline,
-  scrollThroughOlderHistoryPages,
+  expectTimelinePromptVisible,
 } from "../support/helpers/timeline-pagination";
 
-test("does not repeat an assistant block when the current app paginates a published 0.2.5 daemon", async ({
+test("loads history across browser reconnection while retaining old-daemon connections and terminals", async ({
   page,
 }) => {
   test.setTimeout(120_000);
@@ -58,22 +55,8 @@ test("does not repeat an assistant block when the current app paginates a publis
   };
 
   try {
-    for (let index = 0; index < 40; index += 1) {
-      await agent.client.sendAgentMessage(
-        agent.agentId,
-        `timeline-pagination-older-turn-${index}: emit 1 coalesced agent stream updates`,
-      );
-      await agent.client.waitForFinish(agent.agentId, 15_000);
-    }
-    await agent.client.sendAgentMessage(agent.agentId, "build a realistic long mock timeline");
-    await agent.client.waitForFinish(agent.agentId, 20_000);
-    for (let index = 0; index < 20; index += 1) {
-      await agent.client.sendAgentMessage(
-        agent.agentId,
-        `timeline-pagination-turn-${index}: emit 1 coalesced agent stream updates`,
-      );
-      await agent.client.waitForFinish(agent.agentId, 15_000);
-    }
+    await agent.client.sendAgentMessage(agent.agentId, "emit 1 coalesced agent stream updates");
+    await agent.client.waitForFinish(agent.agentId, 15_000);
 
     const host = buildSeededHost({
       serverId,
@@ -89,34 +72,15 @@ test("does not repeat an assistant block when the current app paginates a publis
       { seededHost: host, preferences: buildCreateAgentPreferences() },
     );
 
-    const history = await holdOlderHistoryPages(page, agent, daemon.port);
     await openAgentTimeline(page, agent, serverId);
-    await expectTimelinePromptVisible(
-      page,
-      "timeline-pagination-turn-19: emit 1 coalesced agent stream updates",
-    );
-    await scrollThroughOlderHistoryPages(page, 3, history);
-
-    history.expectRepeatedEntries();
-    await history.expectOwnedTextRendered("Now I have a clearer picture.");
+    await expectTimelinePromptVisible(page, "emit 1 coalesced agent stream updates");
     expect(observationSockets.size).toBe(1);
 
-    await test.step("send a live turn after reconnecting the old daemon", async () => {
-      await daemon.restart();
-      await expect.poll(() => observationSockets.size, { timeout: 30_000 }).toBe(2);
-      await expectComposerEditable(page);
-      await submitMessage(
-        page,
-        "compatibility-after-reconnect: emit 1 coalesced agent stream updates",
-      );
-      await expectTimelinePromptVisible(
-        page,
-        "compatibility-after-reconnect: emit 1 coalesced agent stream updates",
-      );
-      // The browser and the seed client reconnect independently after the restart.
-      await agent.client.connect();
-      await agent.client.waitForFinish(agent.agentId, 20_000);
-      await page.screenshot({ path: test.info().outputPath("old-daemon-live-reconnect.png") });
+    await test.step("reconnect the browser and reload the old daemon history", async () => {
+      observationSockets.clear();
+      await page.reload();
+      await expectTimelinePromptVisible(page, "emit 1 coalesced agent stream updates");
+      await expect.poll(() => observationSockets.size).toBe(1);
     });
 
     await test.step("open a terminal and receive its output", async () => {
@@ -130,7 +94,6 @@ test("does not repeat an assistant block when the current app paginates a publis
       await expect
         .poll(() => getTerminalBufferText(page), { timeout: 15_000 })
         .toContain("compatibility-terminal-output");
-      await page.screenshot({ path: test.info().outputPath("old-daemon-terminal.png") });
       await agent.client.killTerminal(terminalId);
     });
   } finally {

packages/app/e2e/browser/settings-toggle-tab-regression.spec.ts

@@ -1,3 +1,4 @@
+import { openAgentRoute, seedMockAgentWorkspace } from "../support/helpers/mock-agent";
 import { buildHostAgentDetailRoute, buildHostWorkspaceRoute } from "@/utils/host-routes";
 import { expect, test } from "../support/fixtures";
 import { createMockIdleAgent, openWorkspaceWithAgents } from "../support/helpers/archive-tab";
@@ -274,3 +275,123 @@ test.describe("Settings toggle tab regression", () => {
     }
   });
 });
+
+async function selectSendingOption(
+  page: import("@playwright/test").Page,
+  setting: string,
+  option: string,
+) {
+  await page.getByRole("button", { name: new RegExp(`^${setting}:`) }).click();
+  await page.getByRole("menuitem", { name: option, exact: true }).click();
+  await expect(
+    page.getByRole("button", { name: `${setting}: ${option}`, exact: true }),
+  ).toBeVisible();
+}
+
+async function sendDraftWithShortcut(
+  page: import("@playwright/test").Page,
+  draft: string,
+  shortcut: string,
+) {
+  const composer = page.getByRole("textbox", { name: "Message agent..." });
+  await composer.fill(draft);
+  await composer.press(shortcut);
+  await expect(composer).toHaveValue("");
+  await expect(page.getByText(draft, { exact: true })).toBeVisible();
+}
+
+test("send shortcut selection persists and controls the composer", async ({ page }, testInfo) => {
+  test.setTimeout(180_000);
+  const workspace = await seedWorkspace({ repoPrefix: "send-shortcut-" });
+  const modifierLabel = process.platform === "darwin" ? "⌘" : "Ctrl";
+  try {
+    const agent = await createMockIdleAgent(workspace.client, {
+      cwd: workspace.repoPath,
+      workspaceId: workspace.workspaceId,
+      title: "Send shortcut",
+    });
+    await openAgentRouteAndExpectFocused({
+      page,
+      serverId: getServerId(),
+      workspaceId: workspace.workspaceId,
+      agentId: agent.id,
+    });
+    await openComposerTab(page, agent.id);
+    const composer = page.getByRole("textbox", { name: "Message agent..." });
+
+    await test.step("Enter sends by default", async () => {
+      await sendDraftWithShortcut(page, "Default Enter submission", "Enter");
+    });
+    await test.step("choose the explicit modifier shortcut and retain it after reload", async () => {
+      await pressSettingsToggleShortcut(page);
+      await expect(
+        page.getByRole("button", { name: "Send shortcut: Enter", exact: true }),
+      ).toBeVisible();
+      await page.getByRole("button", { name: "Send shortcut: Enter", exact: true }).click();
+      await expect(page.getByRole("menuitem")).toHaveText(["Enter", `${modifierLabel}+Enter`]);
+      // Let the menu opening animation settle for visual QA.
+      await page.waitForTimeout(300);
+      await page.screenshot({ path: testInfo.outputPath("send-shortcut-selector.png") });
+      await page.getByRole("menuitem", { name: `${modifierLabel}+Enter`, exact: true }).click();
+      await page.reload();
+      await expect(
+        page.getByRole("button", { name: `Send shortcut: ${modifierLabel}+Enter`, exact: true }),
+      ).toBeVisible();
+      await pressSettingsToggleShortcut(page);
+      await expect(composer).toBeVisible();
+    });
+    await test.step("Enter and Shift+Enter keep editing; modifier Enter sends", async () => {
+      await composer.fill("First line");
+      await composer.press("Enter");
+      await expect(composer).toHaveValue("First line\n");
+      await composer.press("Shift+Enter");
+      await expect(composer).toHaveValue("First line\n\n");
+      await sendDraftWithShortcut(page, "Sent with Control", "Control+Enter");
+      await sendDraftWithShortcut(page, "Sent with Command", "Meta+Enter");
+    });
+    await test.step("switch back to Enter without changing the default send behavior", async () => {
+      await pressSettingsToggleShortcut(page);
+      await selectSendingOption(page, "Send shortcut", "Enter");
+      await pressSettingsToggleShortcut(page);
+      await composer.fill("Shift still edits");
+      await composer.press("Shift+Enter");
+      await expect(composer).toHaveValue("Shift still edits\n");
+      await sendDraftWithShortcut(page, "Restored Enter submission", "Enter");
+    });
+  } finally {
+    await workspace.cleanup();
+  }
+});
+
+for (const behavior of ["Steer", "Interrupt", "Queue"] as const) {
+  test(`modifier send shortcut follows ${behavior} while an agent runs`, async ({ page }) => {
+    const agent = await seedMockAgentWorkspace({
+      repoPrefix: "running-send-shortcut-",
+      title: "Running send shortcut",
+      model: "one-minute-stream",
+    });
+    const modifierLabel = process.platform === "darwin" ? "⌘" : "Ctrl";
+    try {
+      await openAgentRoute(page, agent);
+      await expect(page.getByRole("textbox", { name: "Message agent..." })).toBeVisible();
+      await pressSettingsToggleShortcut(page);
+      await selectSendingOption(page, "Send shortcut", `${modifierLabel}+Enter`);
+      await selectSendingOption(page, "Default send", behavior);
+      await pressSettingsToggleShortcut(page);
+      await sendDraftWithShortcut(page, "Stay running while I write a follow-up", "Control+Enter");
+      await expect(page.getByRole("button", { name: "Stop agent", exact: true })).toBeVisible();
+      const composer = page.getByRole("textbox", { name: "Message agent..." });
+      await composer.fill("Follow-up");
+      await composer.press("Enter");
+      await expect(composer).toHaveValue("Follow-up\n");
+      await composer.press("Control+Enter");
+      await expect(composer).toHaveValue("");
+      await expect(page.getByText("Follow-up", { exact: true })).toBeVisible();
+      await expect(page.getByRole("button", { name: "Send queued message" })).toHaveCount(
+        behavior === "Queue" ? 1 : 0,
+      );
+    } finally {
+      await agent.cleanup();
+    }
+  });
+}

packages/app/e2e/browser/turn-collapse.spec.ts

@@ -1,8 +1,29 @@
-import type { Page } from "@playwright/test";
+import type { DaemonClient } from "@getpaseo/client/internal/daemon-client";
+import path from "node:path";
+import {
+  holdOlderHistoryPages,
+  userScrollsTimelineToHistoryStart,
+} from "../support/helpers/timeline-pagination";
+import { getActiveTabTestId } from "../support/helpers/launcher";
+import type { Page, Locator } from "@playwright/test";
 import { test, expect } from "../support/fixtures";
 import { expectComposerVisible } from "../support/helpers/composer";
 import { openAgentRoute, seedMockAgentWorkspace } from "../support/helpers/mock-agent";
 
+test.use({
+  e2eDaemonConfig: {
+    version: 1,
+    agents: {
+      providers: {
+        codex: {
+          enabled: true,
+          command: [process.execPath, path.resolve("e2e/fixtures/catalog-codex.mjs")],
+        },
+      },
+    },
+  },
+});
+
 type ChatDisplay = "full" | "collapseToolCalls" | "collapseTurns";
 
 async function useChatDisplay(page: Page, chatDisplay: ChatDisplay): Promise<void> {
@@ -19,7 +40,10 @@ async function seedAnsweredAgent(title: string) {
     initialPrompt: "Why does the chat stop following new output?",
   });
   await agent.client.waitForFinish(agent.agentId, 30_000);
-  await agent.client.sendAgentMessage(agent.agentId, "Make the fix and run the burst script.");
+  await agent.client.sendAgentMessage(
+    agent.agentId,
+    "Make the fix and run the burst script.\n" + "Keep the previous response visible.\n".repeat(40),
+  );
   await agent.client.waitForFinish(agent.agentId, 30_000);
   return agent;
 }
@@ -36,17 +60,84 @@ async function rowsBetweenLatestSummaryAndReply(page: Page): Promise<number> {
   });
 }
 
+async function groupedToolsInsideLatestTurn(page: Page): Promise<string[]> {
+  return page.evaluate(() => {
+    const rows = [...document.querySelectorAll("[data-message-id]")];
+    const start = rows.findLastIndex((row) => row.querySelector("[data-testid=turn-summary]"));
+    const end = rows.findLastIndex((row) => row.querySelector("[data-testid=assistant-message]"));
+    return rows
+      .slice(start + 1, end)
+      .flatMap((row) =>
+        [...row.querySelectorAll("[data-testid=tool-call-group]")].map(
+          (group) => group.textContent ?? "",
+        ),
+      );
+  });
+}
+
+async function expectCompactMessageToggle(prompt: Locator, label: string) {
+  const button = prompt.getByRole("button", { name: label, exact: true });
+  const text = prompt.getByText(label, { exact: true });
+  await expect
+    .poll(
+      async () => {
+        const control = (await button.boundingBox())!;
+        const glyphs = (await text.boundingBox())!;
+        return control.height - glyphs.height;
+      },
+      { message: "The inline toggle adds no vertical space beyond its text" },
+    )
+    .toBe(0);
+}
+
+async function expandAndCollapseLongPrompt(page: Page) {
+  const prompt = page.getByTestId("user-message").last();
+  const before = await prompt.boundingBox();
+  const text = prompt.locator('[data-message-text="true"]');
+  const messageLeft = (await text.boundingBox())!.x;
+  await expect
+    .poll(async () => (await prompt.getByText("Show more", { exact: true }).boundingBox())!.x)
+    .toBe(messageLeft);
+  await expectCompactMessageToggle(prompt, "Show more");
+  await prompt.getByRole("button", { name: "Show more", exact: true }).click();
+  await expect(prompt.getByRole("button", { name: "Show less", exact: true })).toBeVisible();
+  await expect
+    .poll(async () => (await prompt.getByText("Show less", { exact: true }).boundingBox())!.x)
+    .toBe(messageLeft);
+  await expect
+    .poll(async () => (await prompt.boundingBox())?.height ?? 0)
+    .toBeGreaterThan(before!.height);
+  await expectCompactMessageToggle(prompt, "Show less");
+  await prompt.getByRole("button", { name: "Show less", exact: true }).click();
+  await expect.poll(async () => (await prompt.boundingBox())?.height ?? 0).toBe(before!.height);
+  await prompt.scrollIntoViewIfNeeded();
+  const bounds = (await prompt.boundingBox())!;
+  const body = (await text.boundingBox())!;
+  await page.screenshot({
+    path: "/tmp/message-toggle-aligned.png",
+    clip: {
+      x: body.x - 16,
+      y: bounds.y,
+      width: bounds.x + bounds.width - body.x + 16,
+      height: bounds.height,
+    },
+  });
+}
+
 test.describe("Turn collapse", () => {
   test("folds each answered turn behind a summary line that opens it", async ({ page }) => {
     test.setTimeout(120_000);
+    await page.setViewportSize({ width: 1280, height: 1000 });
     await useChatDisplay(page, "collapseTurns");
     const agent = await seedAnsweredAgent("Turn collapse");
     try {
       await openAgentRoute(page, agent);
       await expectComposerVisible(page);
 
+      await expandAndCollapseLongPrompt(page);
+
       const summary = page.getByTestId("turn-summary").last().getByRole("button");
-      await expect(summary).toHaveText(/^Wrote \d+ messages?, edited 1 file/);
+      await expect(summary).toHaveText(/^Edited 1 file/);
       // Text chunks that stream back to back merge into one message, so the reply holds
       // at least the stream's last chunk.
       await expect(page.getByTestId("assistant-message").last()).toHaveText(
@@ -57,6 +148,9 @@ test.describe("Turn collapse", () => {
       await summary.click();
       await expect.poll(() => rowsBetweenLatestSummaryAndReply(page)).toBeGreaterThan(0);
       await expect(summary).toBeInViewport();
+      await summary.evaluate((element) => element.scrollIntoView({ block: "start" }));
+      await page.screenshot({ path: "/tmp/turn-rail-aligned.png" });
+      await expect.poll(() => groupedToolsInsideLatestTurn(page)).toEqual([]);
 
       await summary.click();
       await expect.poll(() => rowsBetweenLatestSummaryAndReply(page)).toBe(0);
@@ -65,3 +159,255 @@ test.describe("Turn collapse", () => {
     }
   });
 });
+
+test("received messages show their sender and open that agent", async ({ page }) => {
+  await page.addInitScript(() =>
+    localStorage.setItem("@paseo:app-settings", JSON.stringify({ theme: "dark" })),
+  );
+  const recipient = await seedMockAgentWorkspace({
+    repoPrefix: "sender-attribution-",
+    title: "Implementation",
+  });
+  try {
+    const sender = await recipient.client.createAgent({
+      provider: "codex",
+      cwd: recipient.cwd,
+      workspaceId: recipient.workspaceId,
+      title: "Reviewer",
+      model: "gpt-6.1-sol",
+      modeId: "full-access",
+    });
+    await recipient.client.sendAgentMessage(
+      recipient.agentId,
+      "I reviewed the turn-grouping changes. Heartbeats now keep their own timing footer, and the previous response stays visible.",
+      { sourceAgentId: sender.id },
+    );
+    await openAgentRoute(page, recipient);
+    await expectComposerVisible(page);
+    const attribution = page.getByRole("button", { name: "Sent by Reviewer", exact: true });
+    await expect(attribution).toBeVisible();
+    await expect(page.getByTestId("user-message").filter({ has: attribution })).toContainText(
+      "I reviewed the turn-grouping changes.",
+    );
+    const labelColor = await attribution
+      .getByText("Sent by Reviewer", { exact: true })
+      .evaluate((element) => getComputedStyle(element).color);
+    await expect(attribution.locator("svg")).toHaveCSS("fill", labelColor);
+    await attribution.scrollIntoViewIfNeeded();
+    await page.screenshot({ path: "/tmp/sender-attribution.png" });
+    await attribution.click();
+    await expect.poll(() => getActiveTabTestId(page)).toContain(sender.id);
+  } finally {
+    await recipient.cleanup();
+  }
+});
+
+async function seedWholeTurnHistory() {
+  const agent = await seedMockAgentWorkspace({
+    repoPrefix: "whole-turn-history-",
+    title: "Whole turns",
+    model: "e2e-fast-stream",
+  });
+  for (const prompt of [
+    ...Array.from(
+      { length: 25 },
+      (_, index) => `Short ${index}: emit 1 coalesced agent stream updates`,
+    ),
+    "Older long turn: emit 60 tool agent stream updates",
+    "Latest long turn: emit 120 tool agent stream updates",
+  ]) {
+    await agent.client.sendAgentMessage(agent.agentId, prompt);
+    await agent.client.waitForFinish(agent.agentId, 15_000);
+  }
+  return agent;
+}
+
+test("loads complete long turns and preserves expansion while revealing older history", async ({
+  page,
+}) => {
+  test.setTimeout(120_000);
+  await useChatDisplay(page, "collapseTurns");
+  const agent = await seedWholeTurnHistory();
+  try {
+    const history = await holdOlderHistoryPages(page, agent);
+    await openAgentRoute(page, agent);
+    await expectComposerVisible(page);
+    const latest = page
+      .getByTestId("turn-summary")
+      .getByRole("button", { name: "Ran 120 commands", exact: true });
+    await expect(latest).toBeVisible();
+    await expect.poll(() => rowsBetweenLatestSummaryAndReply(page)).toBe(0);
+    await latest.click();
+    await expect.poll(() => rowsBetweenLatestSummaryAndReply(page)).toBe(120);
+    await userScrollsTimelineToHistoryStart(page);
+    await history.expectRequestedPages(1);
+    history.releasePage(1);
+    await expect(
+      page
+        .getByTestId("turn-summary")
+        .getByRole("button", { name: "Ran 60 commands", exact: true }),
+    ).toBeVisible();
+    await expect.poll(() => rowsBetweenLatestSummaryAndReply(page)).toBe(120);
+    history.expectNoRepeatedEntries();
+    await latest.scrollIntoViewIfNeeded();
+    await latest.click();
+    await expect.poll(() => rowsBetweenLatestSummaryAndReply(page)).toBe(0);
+  } finally {
+    await agent.cleanup();
+  }
+});
+
+async function useThinkingDisplay(
+  page: Page,
+  autoExpandReasoning: boolean,
+  chatDisplay: ChatDisplay,
+) {
+  await page.addInitScript(
+    (settings) => {
+      localStorage.setItem(
+        "@paseo:app-settings",
+        JSON.stringify({
+          ...settings,
+          chatDisplay: sessionStorage.getItem("e2e-chat-display") ?? settings.chatDisplay,
+        }),
+      );
+    },
+    { autoExpandReasoning, chatDisplay },
+  );
+}
+
+for (const autoExpandReasoning of [false, true]) {
+  test(`reasoning follows Expand thinking (${autoExpandReasoning}) when opening its turn`, async ({
+    page,
+  }) => {
+    await page.setViewportSize({ width: 1280, height: 1000 });
+    await useThinkingDisplay(page, autoExpandReasoning, "collapseToolCalls");
+    const agent = await seedMockAgentWorkspace({
+      repoPrefix: "thinking-group-",
+      title: "Thinking with tools",
+      model: "ten-second-stream",
+      initialPrompt: "Inspect the scroll container",
+    });
+    try {
+      await agent.client.waitForFinish(agent.agentId, 30_000);
+      await openAgentRoute(page, agent);
+      await expectComposerVisible(page);
+      const reasoning = page
+        .getByText(/Need to find the scroll container, the layout effect/)
+        .filter({ visible: true })
+        .first();
+      await expectThinkingPresentation(page, autoExpandReasoning);
+      await switchToCollapsedTurns(page);
+      await expectComposerVisible(page);
+      const summary = page.getByTestId("turn-summary").last().getByRole("button");
+      await expect(summary).toBeVisible();
+      await expect(reasoning).toHaveCount(0);
+      await summary.click();
+      await expect(reasoning).toHaveCount(autoExpandReasoning ? 1 : 0);
+      await expect.poll(() => groupedToolsInsideLatestTurn(page)).toEqual([]);
+      await openOneToolOutput(page);
+      await summary.click();
+      await expect(reasoning).toHaveCount(0);
+    } finally {
+      await agent.cleanup();
+    }
+  });
+}
+
+async function openOneToolOutput(page: Page) {
+  const output = page.getByText(/\[burst\] tick 1 userIsAtBottom=true/).filter({ visible: true });
+  await expect(output).toHaveCount(0);
+  const command = page
+    .getByTestId("tool-call-badge")
+    .filter({ hasText: "node scripts/simulate-stream-burst.mjs" })
+    .first();
+  await command.getByRole("button").first().click();
+  await expect(output.first()).toBeVisible();
+  await command.getByRole("button").first().click();
+  await expect(output).toHaveCount(0);
+}
+
+async function expectThinkingPresentation(page: Page, autoExpandReasoning: boolean) {
+  const reasoning = page
+    .getByText(/Need to find the scroll container, the layout effect/)
+    .filter({ visible: true })
+    .first();
+  if (autoExpandReasoning) {
+    await expect(reasoning).toBeVisible();
+    await expect(page.getByTestId("tool-call-group").filter({ hasText: /thought/ })).toHaveCount(0);
+  } else {
+    await expect(reasoning).toHaveCount(0);
+    const group = page
+      .getByTestId("tool-call-group")
+      .filter({ hasText: /thought/, visible: true })
+      .last();
+    await expect(group).toContainText(/read 1 file/i);
+    await group.getByRole("button").first().click();
+    await expect(reasoning).toBeVisible();
+  }
+}
+
+async function switchToCollapsedTurns(page: Page) {
+  await page.evaluate(() => {
+    sessionStorage.setItem("e2e-chat-display", "collapseTurns");
+  });
+  await page.reload();
+}
+
+test("a scheduled heartbeat opens a separate turn without reopening the previous response", async ({
+  page,
+}) => {
+  test.setTimeout(90_000);
+  await useChatDisplay(page, "collapseTurns");
+  const agent = await seedMockAgentWorkspace({
+    repoPrefix: "heartbeat-turn-",
+    title: "Heartbeat turns",
+    model: "ten-second-stream",
+    initialPrompt: "Inspect the scroll container",
+  });
+  const schedules = agent.client as unknown as Pick<
+    DaemonClient,
+    "scheduleCreate" | "scheduleRunOnce" | "scheduleDelete"
+  >;
+  let scheduleId: string | undefined;
+  try {
+    await agent.client.waitForFinish(agent.agentId, 30_000);
+    await openAgentRoute(page, agent);
+    await expectComposerVisible(page);
+    const summaries = page.getByTestId("turn-summary");
+    await expect(summaries).toHaveCount(1);
+    const previousSummary = await summaries.first().innerText();
+    const previousReplyId = await page
+      .getByTestId("assistant-message")
+      .last()
+      .evaluate((element) => element.closest("[data-message-id]")!.getAttribute("data-message-id"));
+    const created = await schedules.scheduleCreate({
+      name: "Check the completed work",
+      prompt: "Inspect the scroll container again",
+      cadence: { type: "cron", expression: "0 0 1 1 *" },
+      target: { type: "self", agentId: agent.agentId },
+      runOnCreate: false,
+    });
+    expect(created.error).toBeNull();
+    scheduleId = created.schedule!.id;
+    const fired = await schedules.scheduleRunOnce({ id: scheduleId });
+    expect(fired.error).toBeNull();
+    await expect(
+      page.getByTestId("tool-call-badge").filter({ hasText: /^Heartbeat/ }),
+    ).toBeVisible();
+    await expect(summaries.first()).toHaveText(previousSummary);
+    const previousReply = page
+      .locator(`[data-message-id="${previousReplyId}"]`)
+      .getByTestId("assistant-message");
+    await expect(previousReply).toBeVisible();
+    await expect(previousReply).toContainText("(end of synthetic stream)");
+    await agent.client.waitForFinish(agent.agentId, 30_000);
+    await expect(summaries).toHaveCount(2);
+    await expect.poll(() => rowsBetweenLatestSummaryAndReply(page)).toBe(0);
+    await expect(page.getByRole("button", { name: /^Worked for/ })).toHaveCount(2);
+    await page.screenshot({ path: "/tmp/heartbeat-turn-footer.png" });
+  } finally {
+    if (scheduleId) await schedules.scheduleDelete({ id: scheduleId });
+    await agent.cleanup();
+  }
+});

packages/app/e2e/support/helpers/custom-models.ts

@@ -19,6 +19,9 @@ export async function addCustomModel(page: Page, id: string): Promise<void> {
     .getByRole("button", { name: "Add", exact: true })
     .click();
   await expect(page.getByRole("button", { name: `Remove ${id}`, exact: true })).toHaveCount(1);
+  // Config updates before provider refresh finishes and dismisses the add sheet.
+  // Resizing or interacting with the model list must wait for that save to finish.
+  await expect(page.getByTestId("add-custom-model-sheet")).toBeHidden();
 }
 
 export async function removeCustomModel(page: Page, id: string): Promise<void> {

packages/app/e2e/support/helpers/seed-client.ts

@@ -149,7 +149,11 @@ export interface SeedDaemonClient {
     timeout?: number,
   ): Promise<{ status: string }>;
   cancelAgent(agentId: string): Promise<void>;
-  sendAgentMessage(agentId: string, text: string): Promise<void>;
+  sendAgentMessage(
+    agentId: string,
+    text: string,
+    options?: { sourceAgentId?: string },
+  ): Promise<void>;
   waitForFinish(
     agentId: string,
     timeout?: number,

packages/app/package.json

@@ -76,8 +76,8 @@
     "@xterm/addon-search": "^0.17.0-beta.213",
     "@xterm/addon-unicode11": "^0.10.0-beta.213",
     "@xterm/addon-web-links": "^0.13.0-beta.213",
-    "@xterm/addon-webgl": "^0.20.0-beta.212",
-    "@xterm/xterm": "^6.1.0-beta.213",
+    "@xterm/addon-webgl": "0.20.0-beta.291",
+    "@xterm/xterm": "6.1.0-beta.292",
     "buffer": "^6.0.3",
     "expo": "~57.0.30",
     "expo-asset": "~57.0.20",

packages/app/src/agent-stream/footer-spacing.test.ts

@@ -71,7 +71,7 @@ function layoutFor(input: { platform: "web" | "native"; isTurnActive: boolean })
       isTurnActive: input.isTurnActive,
       history: strategy.orderTail([userMessage("user"), assistant]),
       liveHead: [],
-      timingByAssistantId: timingFor(assistant.id),
+      timingByItemId: timingFor(assistant.id),
     }),
   };
 }

packages/app/src/agent-stream/history-window.ts

@@ -1,4 +1,5 @@
 import type { StreamItem } from "@/types/stream";
+import { continuesTurn } from "./turn-membership";
 
 export const DEFAULT_MOUNTED_RECENT_STREAM_ITEMS = 20;
 
@@ -32,7 +33,7 @@ export function findMountedWindowStart(input: {
   }
 
   let startIndex = Math.max(items.length - minMountedCount, 0);
-  while (startIndex > 0 && items[startIndex]?.kind !== "user_message") {
+  while (startIndex > 0 && continuesTurn(items[startIndex - 1], items[startIndex])) {
     startIndex -= 1;
   }
   return startIndex;

packages/app/src/agent-stream/layout.test.ts

@@ -104,7 +104,7 @@ function layoutFor(input: {
       strategy,
       streamHead: input.head ?? [],
     }),
-    timingByAssistantId: timingFor(...(input.timingIds ?? [])),
+    timingByItemId: timingFor(...(input.timingIds ?? [])),
   });
 }
 
@@ -148,7 +148,7 @@ function findLayoutItem(layout: StreamLayout, id: string): StreamLayoutItem {
 }
 
 describe("layoutStream", () => {
-  it("places one response footer after an adjacent tagged tool-only turn", () => {
+  it("keeps separate footers for an assistant turn and an adjacent tool-only turn", () => {
     const priorAssistant = assistantMessage("prior", 1, undefined, "turn-1");
     const nextTool = toolCall("next-tool", 2, "turn-2");
     const layout = layoutFor({
@@ -157,8 +157,8 @@ describe("layoutStream", () => {
       timingIds: [priorAssistant.id],
     });
 
-    expect(layout.auxiliaryTurnFooter?.itemId).toBe(priorAssistant.id);
-    expect(footerOwners(layout)).toEqual([priorAssistant.id]);
+    expect(layout.auxiliaryTurnFooter?.itemId).toBe(nextTool.id);
+    expect(footerOwners(layout)).toEqual([priorAssistant.id, nextTool.id]);
   });
 
   it("recomputes cached history layout when only the live boundary turn changes", () => {
@@ -171,7 +171,7 @@ describe("layoutStream", () => {
       isTurnActive: true,
       history,
       liveHead,
-      timingByAssistantId: timingFor(priorAssistant.id),
+      timingByItemId: timingFor(priorAssistant.id),
     });
 
     liveHead[0] = { ...liveHead[0]!, turnId: "turn-2" };
@@ -180,7 +180,7 @@ describe("layoutStream", () => {
       isTurnActive: true,
       history,
       liveHead,
-      timingByAssistantId: timingFor(priorAssistant.id),
+      timingByItemId: timingFor(priorAssistant.id),
     });
 
     expect(footerOwners(first)).toEqual([]);

packages/app/src/agent-stream/layout.ts

@@ -39,13 +39,13 @@ export interface StreamLayoutInput {
   isTurnActive: boolean;
   history: StreamItem[];
   liveHead: StreamItem[];
-  timingByAssistantId: Map<string, TurnTiming>;
+  timingByItemId: Map<string, TurnTiming>;
 }
 
 interface LayoutSegmentInput {
   strategy: StreamStrategy;
   items: StreamItem[];
-  timingByAssistantId: Map<string, TurnTiming>;
+  timingByItemId: Map<string, TurnTiming>;
   auxiliaryTurnFooter: TurnFooterHost | null;
   hasAuxiliaryFooter: boolean;
   frameOrder: StreamFrameChildOrder;
@@ -57,8 +57,8 @@ interface LayoutSegmentInput {
   phase: "streaming" | "complete";
 }
 
-interface AssistantFooterSource {
-  item: Extract<StreamItem, { kind: "assistant_message" }>;
+interface TurnFooterSource {
+  item: StreamItem;
   items: StreamItem[];
   index: number;
 }
@@ -67,23 +67,26 @@ function createTurnFooterHost(input: {
   item: StreamItem;
   items: StreamItem[];
   index: number;
-  timingByAssistantId: Map<string, TurnTiming>;
+  timingByItemId: Map<string, TurnTiming>;
 }): TurnFooterHost {
   return {
     itemId: input.item.id,
     items: input.items,
-    timing: input.timingByAssistantId.get(input.item.id),
+    timing: input.timingByItemId.get(input.item.id),
     startIndex: input.index,
   };
 }
 
-function findLatestAssistantInResponse(input: {
+function findTurnFooterSource(input: {
   strategy: StreamStrategy;
   items: StreamItem[];
   startIndex: number;
   boundaryAboveItems?: StreamItem[] | null;
   boundaryAboveIndex?: number | null;
-}): AssistantFooterSource | null {
+}): TurnFooterSource | null {
+  const last = input.items[input.startIndex];
+  const toolFallback: TurnFooterSource | null =
+    last?.kind === "tool_call" ? { item: last, items: input.items, index: input.startIndex } : null;
   let items = input.items;
   let index = input.startIndex;
   let canCrossBoundary = true;
@@ -97,7 +100,7 @@ function findLatestAssistantInResponse(input: {
     ) {
       const item = items[index];
       if (!item || (laterItem && !continuesResponse(item, laterItem))) {
-        return null;
+        return toolFallback;
       }
       if (item.kind === "assistant_message") {
         return { item, items, index };
@@ -111,7 +114,7 @@ function findLatestAssistantInResponse(input: {
       input.boundaryAboveIndex === null ||
       input.boundaryAboveIndex === undefined
     ) {
-      return null;
+      return toolFallback;
     }
 
     items = input.boundaryAboveItems;
@@ -131,20 +134,20 @@ function resolveAuxiliaryTurnFooter(input: StreamLayoutInput): TurnFooterHost |
     return null;
   }
 
-  const assistant = findLatestAssistantInResponse({
+  const source = findTurnFooterSource({
     strategy: input.strategy,
     items: footerItems,
     startIndex: latestIndex,
   });
-  if (!assistant) {
+  if (!source) {
     return null;
   }
 
   return createTurnFooterHost({
-    item: assistant.item,
-    items: assistant.items,
-    index: assistant.index,
-    timingByAssistantId: input.timingByAssistantId,
+    item: source.item,
+    items: source.items,
+    index: source.index,
+    timingByItemId: input.timingByItemId,
   });
 }
 
@@ -154,7 +157,7 @@ function resolveCompletedFooter(input: {
   index: number;
   item: StreamItem;
   belowItem: StreamItem | null;
-  timingByAssistantId: Map<string, TurnTiming>;
+  timingByItemId: Map<string, TurnTiming>;
   auxiliaryTurnFooter: TurnFooterHost | null;
   boundaryAboveItems: StreamItem[] | null;
   boundaryAboveIndex: number | null;
@@ -163,21 +166,21 @@ function resolveCompletedFooter(input: {
     return null;
   }
 
-  const assistant = findLatestAssistantInResponse({
+  const source = findTurnFooterSource({
     strategy: input.strategy,
     items: input.items,
     startIndex: input.index,
     boundaryAboveItems: input.boundaryAboveItems,
     boundaryAboveIndex: input.boundaryAboveIndex,
   });
-  if (!assistant || input.auxiliaryTurnFooter?.itemId === assistant.item.id) {
+  if (!source || input.auxiliaryTurnFooter?.itemId === source.item.id) {
     return null;
   }
   return createTurnFooterHost({
-    item: assistant.item,
-    items: assistant.items,
-    index: assistant.index,
-    timingByAssistantId: input.timingByAssistantId,
+    item: source.item,
+    items: source.items,
+    index: source.index,
+    timingByItemId: input.timingByItemId,
   });
 }
 
@@ -306,7 +309,7 @@ function layoutSegmentItem(
     index,
     item,
     belowItem,
-    timingByAssistantId: input.timingByAssistantId,
+    timingByItemId: input.timingByItemId,
     auxiliaryTurnFooter: input.auxiliaryTurnFooter,
     boundaryAboveItems: input.boundaryAboveItems,
     boundaryAboveIndex: input.boundaryAboveIndex,
@@ -375,7 +378,7 @@ export function layoutStream(input: StreamLayoutInput): StreamLayout {
       history = layoutSegment({
         strategy: input.strategy,
         items: input.history,
-        timingByAssistantId: input.timingByAssistantId,
+        timingByItemId: input.timingByItemId,
         auxiliaryTurnFooter,
         hasAuxiliaryFooter,
         frameOrder,
@@ -395,7 +398,7 @@ export function layoutStream(input: StreamLayoutInput): StreamLayout {
   const liveHead = layoutSegment({
     strategy: input.strategy,
     items: input.liveHead,
-    timingByAssistantId: input.timingByAssistantId,
+    timingByItemId: input.timingByItemId,
     auxiliaryTurnFooter,
     hasAuxiliaryFooter,
     frameOrder,

packages/app/src/agent-stream/model.test.ts

@@ -69,8 +69,8 @@ describe("buildAgentStreamRenderModel", () => {
       historyStart: 2,
     });
 
-    expect(model.turnTiming.byAssistantId.has("hidden-a")).toBe(false);
-    expect(model.turnTiming.byAssistantId.get("visible-a")).toEqual({
+    expect(model.turnTiming.byItemId.has("hidden-a")).toBe(false);
+    expect(model.turnTiming.byItemId.get("visible-a")).toEqual({
       completedAt: tail[3]?.timestamp,
       durationMs: 1000,
     });
@@ -184,7 +184,7 @@ describe("buildAgentStreamRenderModel", () => {
     });
 
     expect(model.turnTiming.runningStartedAt).toBe(tail[0]?.timestamp);
-    expect(model.turnTiming.byAssistantId.has("live-a")).toBe(false);
+    expect(model.turnTiming.byItemId.has("live-a")).toBe(false);
   });
 
   it("maps completed turn timing to assistant ids across committed history and live head", () => {
@@ -201,7 +201,7 @@ describe("buildAgentStreamRenderModel", () => {
     });
 
     expect(model.turnTiming.runningStartedAt).toBe(null);
-    expect(model.turnTiming.byAssistantId.get("live-a")).toEqual({
+    expect(model.turnTiming.byItemId.get("live-a")).toEqual({
       completedAt: head[0]?.timestamp,
       durationMs: 3000,
     });
@@ -220,7 +220,7 @@ describe("buildAgentStreamRenderModel", () => {
     });
 
     expect(model.segments.historyMounted.map((item) => item.id)).toEqual(["a1", "u1"]);
-    expect(model.turnTiming.byAssistantId.get("a1")).toEqual({
+    expect(model.turnTiming.byItemId.get("a1")).toEqual({
       completedAt: tail[1]?.timestamp,
       durationMs: 3000,
     });
@@ -238,7 +238,7 @@ describe("buildAgentStreamRenderModel", () => {
       isMobileBreakpoint: false,
     });
 
-    expect(model.turnTiming.byAssistantId.size).toBe(0);
+    expect(model.turnTiming.byItemId.size).toBe(0);
   });
 
   it.each(["web", "native"] as const)(
@@ -274,10 +274,10 @@ describe("buildAgentStreamRenderModel", () => {
 
       expect(second.history).toBe(first.history);
       expect(second.segments.historyMounted).toBe(first.segments.historyMounted);
-      expect(second.turnTiming.byAssistantId).toBe(first.turnTiming.byAssistantId);
+      expect(second.turnTiming.byItemId).toBe(first.turnTiming.byItemId);
       expect(first.history).toHaveLength(20);
-      expect(first.turnTiming.byAssistantId.has("a29")).toBe(false);
-      expect(first.turnTiming.byAssistantId.get("a38")).toEqual({
+      expect(first.turnTiming.byItemId.has("a29")).toBe(false);
+      expect(first.turnTiming.byItemId.get("a38")).toEqual({
         completedAt: tail[77]?.timestamp,
         durationMs: 1000,
       });

packages/app/src/agent-stream/presentation.test.ts

@@ -588,3 +588,129 @@ describe("timeline presentation", () => {
     expect(projectTimelineItems([source], () => [])).toEqual([]);
   });
 });
+
+it("opening a turn reveals individual calls rather than another tool group", () => {
+  const present = createStreamPresentation();
+  const timestamp = new Date();
+  const tail: StreamItem[] = [
+    { kind: "user_message", id: "prompt", text: "Work", timestamp },
+    toolCall("one", "Bash"),
+    toolCall("two", "Bash"),
+    { kind: "assistant_message", id: "reply", text: "Done", timestamp },
+  ];
+  const result = present({
+    ...presentationOptions,
+    transform: undefined,
+    tail,
+    head: [],
+    display: "collapseTurns",
+    isTurnActive: false,
+    expandedTurnHostIds: new Set(["prompt"]),
+  });
+  expect(result.tail.map((item) => item.id)).toEqual(tail.map((item) => item.id));
+  expect(result.groupsByHostId.size).toBe(0);
+});
+
+it("presents received agent messages as attributed bubbles with the original turn identity", () => {
+  const call = toolCall("received", "agent_message");
+  if (call.payload.source !== "agent") throw new Error("Expected agent tool");
+  call.turnId = "turn";
+  call.payload.data.agentMessage = {
+    event: "message",
+    sender: { id: "sender", title: "Reviewer" },
+    text: "Ready",
+  };
+  const result = createStreamPresentation()({
+    ...presentationOptions,
+    transform: undefined,
+    tail: [call],
+    head: [],
+  });
+  expect(result.tail[0]).toMatchObject({
+    kind: "user_message",
+    id: call.id,
+    turnId: "turn",
+    text: "Ready",
+    sender: { id: "sender", title: "Reviewer" },
+  });
+});
+
+it("does not reopen the previous turn while a new run waits for its first row", () => {
+  const timestamp = new Date();
+  const tail: StreamItem[] = [
+    { kind: "user_message", id: "prompt", text: "Work", timestamp },
+    toolCall("one", "Bash"),
+    { kind: "assistant_message", id: "reply", text: "Done", timestamp },
+  ];
+  for (const item of tail) item.turnId = "completed";
+  const result = createStreamPresentation()({
+    ...presentationOptions,
+    transform: undefined,
+    tail,
+    head: [],
+    display: "collapseTurns",
+    isTurnActive: true,
+    activeTurnId: "new",
+  });
+  expect(result.tail.map((item) => item.id)).toEqual(["prompt", "reply"]);
+});
+
+it("groups reasoning with tools unless Expand thinking is enabled, including setting changes", () => {
+  const present = createStreamPresentation();
+  const timestamp = new Date();
+  const thought: StreamItem = {
+    kind: "thought",
+    id: "thought",
+    text: "Consider this",
+    status: "ready",
+    timestamp,
+  };
+  const tail: StreamItem[] = [toolCall("one", "Bash"), thought, toolCall("two", "Bash")];
+  for (const item of tail) item.turnId = "run";
+  const input = {
+    ...presentationOptions,
+    transform: undefined,
+    tail,
+    head: [],
+    display: "collapseToolCalls" as const,
+    isTurnActive: false,
+  };
+  const grouped = present({ ...input, autoExpandReasoning: false });
+  expect(grouped.tail).toHaveLength(1);
+  expect(grouped.groupsByHostId.get("tool-one")?.run.calls).toEqual(tail);
+  const separate = present({ ...input, autoExpandReasoning: true });
+  expect(separate.tail.map((item) => item.id)).toEqual(["tool-one", "thought", "tool-two"]);
+  expect(separate.groupsByHostId.has("thought")).toBe(false);
+  const next = { ...thought, id: "next", turnId: "next-run" };
+  const bounded = present({ ...input, tail: [...tail, next], autoExpandReasoning: false });
+  expect(bounded.tail.map((item) => item.id)).toEqual(["tool-one", "next"]);
+});
+
+it.each([false, true])(
+  "reveals raw reasoning when opening a turn (Expand thinking %s)",
+  (autoExpandReasoning) => {
+    const timestamp = new Date();
+    const tail: StreamItem[] = [
+      { kind: "user_message", id: "prompt", text: "Work", timestamp },
+      { kind: "thought", id: "thought", text: "Consider this", status: "ready", timestamp },
+      toolCall("one", "Bash"),
+      { kind: "assistant_message", id: "reply", text: "Done", timestamp },
+    ];
+    const input = {
+      ...presentationOptions,
+      transform: undefined,
+      tail,
+      head: [],
+      display: "collapseTurns" as const,
+      isTurnActive: false,
+      autoExpandReasoning,
+    };
+    const present = createStreamPresentation();
+    const closed = present(input);
+    expect(closed.tail.some((item) => item.id === "thought")).toBe(false);
+    const opened = present({ ...input, expandedTurnHostIds: new Set(["prompt"]) });
+    expect(opened.tail).toEqual(tail);
+    expect(opened.turns.nestedItemIds.has("thought")).toBe(true);
+    expect(opened.groupsByHostId.size).toBe(0);
+  },
+);

packages/app/src/agent-stream/presentation.ts

@@ -1,3 +1,4 @@
+import { isTurnBoundary } from "./turn-membership";
 import type { ChatDisplay } from "@/hooks/use-settings";
 import type { TimelineItemTransform } from "@/plugins/timeline/model";
 import { projectPluginTimelineItems } from "@/plugins/timeline/projection";
@@ -16,9 +17,11 @@ interface PresentationInput {
   head: StreamItem[];
   transform: TimelineItemTransform | undefined;
   display: ChatDisplay;
+  autoExpandReasoning?: boolean;
   /** User messages whose collapsed turn the reader opened. */
   expandedTurnHostIds: ReadonlySet<string>;
   isTurnActive: boolean;
+  activeTurnId?: string | null;
 }
 
 export interface StreamPresentation extends ToolCallDetailProjection {
@@ -55,6 +58,7 @@ export function createStreamPresentation() {
   let historyTransform: TimelineItemTransform | undefined;
   let historyRows: StreamItem[] = [];
   let preparedTail: StreamItem[] | undefined;
+  let preparedAutoExpandReasoning: boolean | undefined;
   let preparedLevel: ToolCallDetailLevel | undefined;
   let preparedHistory: PreparedToolCallHistory | null = null;
   let collapsedSource: StreamItem[] | undefined;
@@ -63,6 +67,22 @@ export function createStreamPresentation() {
   let collapsed: TurnCollapse | undefined;
 
   function presentRows(item: StreamItem): StreamItem[] {
+    if (item.kind === "tool_call" && item.payload.source === "agent") {
+      const message = item.payload.data.agentMessage;
+      if (message?.event === "message") {
+        return [
+          {
+            kind: "user_message",
+            id: item.id,
+            turnId: item.turnId,
+            timelineCursor: item.timelineCursor,
+            timestamp: item.timestamp,
+            text: message.text,
+            sender: message.sender,
+          },
+        ];
+      }
+    }
     return [item.kind === "user_message" ? presentUserMessage(item) : item];
   }
 
@@ -75,7 +95,14 @@ export function createStreamPresentation() {
     }
     // Live text updates reach the head only, so the folded history is reused until the
     // retained rows, the latest turn's liveness, or the reader's expanded turns change.
-    const isLatestTurnOpen = input.isTurnActive || projection.head.length > 0;
+    const isLatestTurnOpen =
+      (input.isTurnActive || projection.head.length > 0) &&
+      !isTurnBoundary(projection.tail.at(-1) ?? null, projection.head[0] ?? null) &&
+      !(
+        input.activeTurnId &&
+        projection.tail.at(-1)?.turnId &&
+        input.activeTurnId !== projection.tail.at(-1)?.turnId
+      );
     if (
       !collapsed ||
       collapsedSource !== projection.tail ||
@@ -93,7 +120,20 @@ export function createStreamPresentation() {
       collapsedExpandedHostIds = input.expandedTurnHostIds;
     }
     const { tail, ...turns } = collapsed;
-    return { ...projection, tail, turns };
+    if (turns.nestedItemIds.size === 0) return { ...projection, tail, turns };
+    // Opening a turn reveals its raw calls; those rows must not become group hosts again.
+    const withoutExpandedRows = (groups: StreamPresentation["groupsByHostId"]) => ({
+      size: groups.size - [...turns.nestedItemIds].filter((id) => groups.has(id)).length,
+      get: (id: string) => (turns.nestedItemIds.has(id) ? undefined : groups.get(id)),
+      has: (id: string) => !turns.nestedItemIds.has(id) && groups.has(id),
+    });
+    return {
+      ...projection,
+      tail,
+      turns,
+      groupsByHostId: withoutExpandedRows(projection.groupsByHostId),
+      historyGroupUpdatesByHostId: withoutExpandedRows(projection.historyGroupUpdatesByHostId),
+    };
   }
 
   return (input: PresentationInput): StreamPresentation => {
@@ -111,10 +151,15 @@ export function createStreamPresentation() {
       const blocks = presentRows(item);
       head.push(...blocks);
     }
-    if (preparedTail !== historyRows || preparedLevel !== level) {
-      preparedHistory = prepareToolCallHistory(level, historyRows);
+    if (
+      preparedTail !== historyRows ||
+      preparedLevel !== level ||
+      preparedAutoExpandReasoning !== input.autoExpandReasoning
+    ) {
+      preparedHistory = prepareToolCallHistory(level, historyRows, input.autoExpandReasoning);
       preparedTail = historyRows;
       preparedLevel = level;
+      preparedAutoExpandReasoning = input.autoExpandReasoning;
     }
     return collapse(
       projectToolCallDetailLevel({

packages/app/src/agent-stream/render-strategy.test.ts

@@ -214,7 +214,7 @@ describe("neighbor and traversal semantics", () => {
     ).toBe("assistant-1\n\nassistant-2");
   });
 
-  it("collects copy content across adjacent turns without a visible prompt", () => {
+  it("keeps copied content within the canonical turn without a visible prompt", () => {
     const chronological: StreamItem[] = [
       { ...assistantMessage("a1", "first turn", 1), turnId: "turn-1" },
       { ...toolCall("tool", 2), turnId: "turn-2" },
@@ -228,7 +228,7 @@ describe("neighbor and traversal semantics", () => {
         items: chronological,
         startIndex: 2,
       }),
-    ).toBe("first turn\n\nsecond turn");
+    ).toBe("second turn");
   });
 
   it("returns undefined neighbor when index would be out of bounds", () => {

packages/app/src/agent-stream/strategy-web.test.tsx

@@ -7,7 +7,7 @@ import { act } from "react";
 import { createRoot, type Root } from "react-dom/client";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import { RetainedPanelActivity } from "@/components/retained-panel";
-import type { StreamItem } from "@/types/stream";
+import { reduceStreamUpdate, type StreamItem } from "@/types/stream";
 import type { StreamRenderInput, StreamSegmentRenderers, StreamViewportHandle } from "./strategy";
 import { createWebStreamStrategy } from "./strategy-web";
 
@@ -131,6 +131,79 @@ describe("createWebStreamStrategy", () => {
     vi.restoreAllMocks();
   });
 
+  it.each(["liveHead", "historyMounted"] as const)(
+    "keeps one rendered tool row after late prior-turn updates in %s",
+    (lane) => {
+      const strategy = createWebStreamStrategy({ isMobileBreakpoint: true });
+      container = document.createElement("div");
+      document.body.appendChild(container);
+      root = createRoot(container);
+      const input: StreamRenderInput = {
+        agentId: "agent",
+        segments: { historyVirtualized: [], historyMounted: [], liveHead: [] },
+        boundary: {
+          hasVirtualizedHistory: false,
+          hasMountedHistory: lane === "historyMounted",
+          hasLiveHead: lane === "liveHead",
+        },
+        renderers: createRenderers(() => {}),
+        listEmptyComponent: null,
+        viewportRef: React.createRef<StreamViewportHandle>(),
+        routeBottomAnchorRequest: null,
+        isAuthoritativeHistoryReady: true,
+        onNearBottomChange: () => {},
+        onNearHistoryStart: () => true,
+        isLoadingOlderHistory: false,
+        hasOlderHistory: false,
+        olderHistoryProgressKey: null,
+        scrollEnabled: true,
+        listStyle: null,
+        baseListContentContainerStyle: null,
+        forwardListContentContainerStyle: null,
+        contentMaxWidth: DEFAULT_CONTENT_MAX_WIDTH,
+      };
+      let items: StreamItem[] = [];
+      const updates = [
+        { callId: "background", turnId: "old", status: "running" },
+        { callId: "exec", turnId: "current", status: "running" },
+        { callId: "background", turnId: "old", status: "completed" },
+        { callId: "exec", turnId: "current", status: "completed" },
+      ] as const;
+      for (const [index, update] of updates.entries()) {
+        items = reduceStreamUpdate(
+          items,
+          {
+            type: "timeline",
+            provider: "codex",
+            turnId: update.turnId,
+            item: {
+              type: "tool_call",
+              callId: update.callId,
+              name: "exec_command",
+              status: update.status,
+              error: null,
+              detail: { type: "shell", command: update.callId },
+            },
+          },
+          new Date(index),
+        );
+        act(() =>
+          root?.render(
+            strategy.render({
+              ...input,
+              segments: { ...input.segments, [lane]: items },
+            }),
+          ),
+        );
+      }
+      const rows = [...container.querySelectorAll("[data-history-row-id]")];
+      expect(rows.map((row) => row.getAttribute("data-history-row-id"))).toEqual([
+        "agent_tool_turn:old/background",
+        "agent_tool_turn:current/exec",
+      ]);
+    },
+  );
+
   it("mounts virtualized history without recursive row measurement updates", () => {
     const rowRenderCount = vi.fn();
     const strategy = createWebStreamStrategy({ isMobileBreakpoint: true });

packages/app/src/agent-stream/stream-tick.bench.ts

@@ -110,7 +110,7 @@ function runTicks(input: { tail: StreamItem[]; historyStart: number; heads: Stre
       isTurnActive: true,
       history: model.history,
       liveHead: model.segments.liveHead,
-      timingByAssistantId: model.turnTiming.byAssistantId,
+      timingByItemId: model.turnTiming.byItemId,
     });
   }
 }

packages/app/src/agent-stream/turn-collapse/model.test.ts

@@ -48,6 +48,41 @@ function collapse(tail: StreamItem[], options: Partial<CollapseTurnsInput> = {})
 const ids = (items: StreamItem[]) => items.map((item) => item.id);
 
 describe("collapseTurns", () => {
+  it("keeps lifecycle events and compaction recognizable beside a semantic action summary", () => {
+    const create = shell("create");
+    if (create.payload.source !== "agent") throw new Error("Expected agent tool");
+    create.payload.data.name = "mcp__paseo__create_agent";
+    create.payload.data.detail = { type: "unknown", input: { title: "Side fix" }, output: null };
+    const finished = shell("finished");
+    if (finished.payload.source !== "agent") throw new Error("Expected agent tool");
+    finished.payload.data.name = "agent_notification";
+    finished.payload.data.agentMessage = {
+      event: "finished",
+      sender: { id: "worker", title: "PR helper" },
+      text: "Finished",
+    };
+    const items: StreamItem[] = [
+      user("u1"),
+      create,
+      finished,
+      {
+        kind: "compaction",
+        id: "compaction",
+        timestamp: at,
+        status: "completed",
+      } satisfies StreamItem,
+      shell("bash"),
+      reply("done"),
+    ].map((item) => Object.assign(item, { turnId: "same-run" }));
+    const result = collapse(items);
+    expect(ids(result.tail)).toEqual(["u1", "finished", "compaction", "done"]);
+    expect(result.turnsByHostId.get("u1")?.summary.tools).toMatchObject({
+      commandCount: 1,
+      otherToolCount: 0,
+      paseoActions: { "Created agent": 1 },
+    });
+  });
+
   it("folds a finished turn's work into its user message and keeps the reply", () => {
     const result = collapse([
       user("u1"),
@@ -63,7 +98,6 @@ describe("collapseTurns", () => {
       hostId: "u1",
       expanded: false,
       summary: {
-        messageCount: 1,
         tools: expect.objectContaining({ commandCount: 2 }),
       },
     });
@@ -121,6 +155,34 @@ describe("collapseTurns", () => {
     expect(result.turnsByHostId.size).toBe(0);
   });
 
+  it("keeps a completed response folded when a promptless canonical turn starts", () => {
+    const first = [user("u1"), shell("c1"), reply("r1")].map((item) =>
+      Object.assign(item, { turnId: "first" }),
+    );
+    const next = { ...shell("heartbeat"), turnId: "second" };
+    const result = collapse([...first, next], { isLatestTurnOpen: true });
+    expect(ids(result.tail)).toEqual(["u1", "r1", "heartbeat"]);
+    expect(result.turnsByHostId.has("u1")).toBe(true);
+  });
+
+  it("keeps mid-turn messages visible when work is folded", () => {
+    const tail = [user("prompt"), shell("work"), user("steer"), shell("more"), reply("done")];
+    for (const item of tail) item.turnId = "same-turn";
+    const result = collapse(tail);
+    expect(ids(result.tail)).toEqual(["prompt", "steer", "done"]);
+    expect(result.hostIdByFoldedMessageId.has("steer")).toBe(false);
+  });
+
+  it("reveals every raw call inside an expanded turn", () => {
+    const calls = [shell("one"), shell("two")];
+    const result = collapse([user("prompt"), calls[0]!, reply("done")], {
+      expandedHostIds: new Set(["prompt"]),
+      getGroupedCalls: (id) => (id === "one" ? calls : undefined),
+    });
+    expect(ids(result.tail)).toEqual(["prompt", "one", "two", "done"]);
+    expect([...result.nestedItemIds]).toEqual(["one", "two"]);
+  });
+
   it("counts every call a tool-call group row stands for", () => {
     const group = [shell("c1"), shell("c2"), shell("c3")];
     const result = collapse([user("u1"), group[0]!, reply("final")], {

packages/app/src/agent-stream/turn-collapse/model.ts

@@ -1,13 +1,18 @@
-import { getStreamItemMessageId, type StreamItem, type ToolCallItem } from "@/types/stream";
+import { isTurnBoundary, isTurnTrigger } from "../turn-membership";
+import {
+  getStreamItemMessageId,
+  type StreamItem,
+  type ThoughtItem,
+  type ToolCallItem,
+} from "@/types/stream";
 import { summarizeToolCalls, type OverviewSummary } from "@/tool-calls/detail-level/overview/model";
 
 export interface TurnSummary {
-  messageCount: number;
   tools: OverviewSummary;
 }
 
 export interface CollapsedTurn {
-  /** The user message the turn answers. Its row carries the turn's summary line. */
+  /** The input or first loaded row that carries the turn's summary line. */
   hostId: string;
   expanded: boolean;
   summary: TurnSummary;
@@ -28,7 +33,7 @@ export interface CollapseTurnsInput {
   isLatestTurnOpen: boolean;
   expandedHostIds: ReadonlySet<string>;
   /** The calls a tool-call group row stands for; undefined for a single call. */
-  getGroupedCalls: (itemId: string) => readonly ToolCallItem[] | undefined;
+  getGroupedCalls: (itemId: string) => readonly (ToolCallItem | ThoughtItem)[] | undefined;
 }
 
 const EMPTY_TURNS: ReadonlyMap<string, CollapsedTurn> = new Map();
@@ -39,17 +44,21 @@ function summarizeTurn(
   items: readonly StreamItem[],
   getGroupedCalls: CollapseTurnsInput["getGroupedCalls"],
 ): TurnSummary {
-  const calls: ToolCallItem[] = [];
-  let messageCount = 0;
+  const calls: (ToolCallItem | ThoughtItem)[] = [];
   for (const item of items) {
-    if (item.kind === "assistant_message") messageCount += 1;
-    else if (item.kind === "tool_call") calls.push(...(getGroupedCalls(item.id) ?? [item]));
+    if ((item.kind === "tool_call" || item.kind === "thought") && !isTurnTrigger(item))
+      calls.push(...(getGroupedCalls(item.id) ?? [item]));
   }
-  return { messageCount, tools: summarizeToolCalls(calls) };
+  return { tools: summarizeToolCalls(calls) };
 }
 
 function hasWork(summary: TurnSummary): boolean {
-  return summary.messageCount > 0 || Object.values(summary.tools).some((count) => count > 0);
+  const { paseoActions, thoughtCount: _thoughtCount, ...counts } = summary.tools;
+  return Object.keys(paseoActions).length > 0 || Object.values(counts).some((count) => count > 0);
+}
+
+function staysVisibleWhenCollapsed(item: StreamItem): boolean {
+  return isTurnTrigger(item) || item.kind === "compaction";
 }
 
 function findLastAssistantIndex(tail: StreamItem[], start: number, end: number): number {
@@ -63,7 +72,7 @@ function findLastAssistantIndex(tail: StreamItem[], start: number, end: number):
  * Folds each answered turn into its user message: everything the agent did before its last
  * message collapses into one summary line, and that message stays in the chat. A turn folds
  * only once it is complete, its user message is loaded, and it sent messages or called tools
- * before its reply. Thoughts fold with the turn but are not counted.
+ * before its reply. Reasoning is revealed only when the turn opens.
  */
 export function collapseTurns(input: CollapseTurnsInput): TurnCollapse {
   const { tail } = input;
@@ -77,28 +86,47 @@ export function collapseTurns(input: CollapseTurnsInput): TurnCollapse {
     const host = tail[runStart - 1];
     const isClosed = runEnd < tail.length || !input.isLatestTurnOpen;
     const replyIndex = findLastAssistantIndex(tail, runStart, runEnd);
-    if (host?.kind !== "user_message" || !isClosed || replyIndex <= runStart) {
+    if (
+      !host ||
+      (host.kind !== "user_message" && host.kind !== "tool_call") ||
+      !isClosed ||
+      replyIndex <= runStart
+    ) {
       output.push(...tail.slice(runStart, runEnd));
       return;
     }
     const folded = tail.slice(runStart, replyIndex);
     const summary = summarizeTurn(folded, input.getGroupedCalls);
-    if (!hasWork(summary)) {
+    if (!hasWork(summary) && !folded.some((item) => item.kind === "assistant_message")) {
       output.push(...tail.slice(runStart, runEnd));
       return;
     }
     const expanded = input.expandedHostIds.has(host.id);
     turnsByHostId.set(host.id, { hostId: host.id, expanded, summary });
-    for (const item of folded) {
+    const revealed = expanded
+      ? folded.flatMap<StreamItem>((item) =>
+          item.kind === "tool_call" || item.kind === "thought"
+            ? [...(input.getGroupedCalls(item.id) ?? [item])]
+            : [item],
+        )
+      : folded;
+    for (const item of revealed) {
+      if (staysVisibleWhenCollapsed(item)) continue;
       hostIdByFoldedMessageId.set(getStreamItemMessageId(item), host.id);
       if (expanded) nestedItemIds.add(item.id);
     }
-    if (expanded) output.push(...folded);
+    output.push(
+      ...(expanded ? revealed : folded.filter((item) => staysVisibleWhenCollapsed(item))),
+    );
     output.push(...tail.slice(replyIndex, runEnd));
   };
 
   for (let index = 0; index < tail.length; index += 1) {
-    if (tail[index]?.kind !== "user_message") continue;
+    if (
+      !(index === 0 && isTurnTrigger(tail[index]!)) &&
+      !isTurnBoundary(tail[index - 1] ?? null, tail[index] ?? null)
+    )
+      continue;
     flushRun(index);
     output.push(tail[index]!);
     runStart = index + 1;
@@ -114,7 +142,10 @@ export function collapseTurns(input: CollapseTurnsInput): TurnCollapse {
     };
   }
   return {
-    tail: output.length === tail.length ? tail : output,
+    tail:
+      output.length === tail.length && output.every((item, index) => item === tail[index])
+        ? tail
+        : output,
     turnsByHostId,
     nestedItemIds,
     hostIdByFoldedMessageId,

packages/app/src/agent-stream/turn-collapse/summary-line.tsx

@@ -1,4 +1,4 @@
-import { memo, useCallback, useMemo } from "react";
+import { memo, useCallback } from "react";
 import { useTranslation } from "react-i18next";
 import { Summary } from "lucide-react-native";
 import { ExpandableBadge } from "@/components/message";
@@ -17,19 +17,7 @@ export const TurnSummaryLine = memo(function TurnSummaryLine({
   onExpandedChange: (hostId: string, expanded: boolean) => void;
 }) {
   const { t } = useTranslation();
-  const { messageCount, tools } = turn.summary;
-  const messageParts = useMemo(
-    () =>
-      messageCount > 0
-        ? [
-            t(`turnSummary.messages.${messageCount === 1 ? "one" : "other"}`, {
-              count: messageCount,
-            }),
-          ]
-        : [],
-    [messageCount, t],
-  );
-  const label = useOverviewSummaryLabel(tools, messageParts);
+  const label = useOverviewSummaryLabel(turn.summary.tools) || t("turnSummary.details");
   const toggle = useCallback(
     () => onExpandedChange(turn.hostId, !turn.expanded),
     [onExpandedChange, turn.expanded, turn.hostId],

packages/app/src/agent-stream/turn-footer.tsx

@@ -197,7 +197,7 @@ function CompletedTurnFooter({
   return (
     <View style={stylesheet.turnFooterSlot}>
       <AssistantTurnFooter
-        getContent={getContent}
+        getContent={items[startIndex]?.kind === "assistant_message" ? getContent : undefined}
         completedAt={timing?.completedAt}
         durationMs={timing?.durationMs}
         onFork={boundary && onForkAssistantTurn ? handleFork : undefined}

packages/app/src/agent-stream/turn-membership.test.ts

@@ -53,7 +53,7 @@ function layoutFor(items: StreamItem[], isTurnActive: boolean) {
       isTurnActive,
       history: model.segments.historyMounted,
       liveHead: model.segments.liveHead,
-      timingByAssistantId: model.turnTiming.byAssistantId,
+      timingByItemId: model.turnTiming.byItemId,
     }),
   };
 }
@@ -67,6 +67,24 @@ function completedFooterIds(layout: ReturnType<typeof layoutFor>["layout"]): str
 }
 
 describe("canonical turn membership", () => {
+  it("uses trigger fallback for missing IDs without pretending to recover batching", () => {
+    const previous = assistant("reply", 1, "first");
+    const trigger = runningTool("heartbeat", 2, "first");
+    if (trigger.kind !== "tool_call" || trigger.payload.source !== "agent")
+      throw new Error("Expected agent tool");
+    trigger.payload.data.name = "heartbeat";
+    expect(continuesTurn(previous, trigger)).toBe(true);
+    delete trigger.turnId;
+    expect(continuesTurn(previous, trigger)).toBe(false);
+    trigger.payload.data.name = "agent_message";
+    trigger.payload.data.agentMessage = {
+      event: "finished",
+      sender: { id: "worker" },
+      text: "Done",
+    };
+    expect(continuesTurn(previous, trigger)).toBe(false);
+  });
+
   it("stops tagged traversal at every mismatching turn ID", () => {
     expect(continuesTurn(assistant("first", 1, "turn-1"), runningTool("next", 2, "turn-2"))).toBe(
       false,
@@ -76,7 +94,7 @@ describe("canonical turn membership", () => {
     );
   });
 
-  it("renders adjacent turns without visible prompts as one response", () => {
+  it("renders a separate footer for each canonical turn without visible prompts", () => {
     const items = [
       user("prompt", 1, "turn-1"),
       assistant("first reply", 2, "turn-1"),
@@ -88,7 +106,11 @@ describe("canonical turn membership", () => {
 
     const completed = layoutFor(items, false);
 
-    expect(completedFooterIds(completed.layout)).toEqual(["heartbeat-2-reply"]);
+    expect(completedFooterIds(completed.layout)).toEqual([
+      "first reply",
+      "heartbeat-1-reply",
+      "heartbeat-2-reply",
+    ]);
     expect(completed.layout.auxiliaryTurnFooter?.timing).toEqual({
       completedAt: at(6),
       durationMs: null,
@@ -123,7 +145,7 @@ describe("canonical turn membership", () => {
     const completedItems = [...build(turnId), assistant("done", 9, turnId)];
     const completed = layoutFor(completedItems, false);
     expect(completedFooterIds(completed.layout)).toEqual(["done"]);
-    expect(completed.model.turnTiming.byAssistantId.get("done")).toMatchObject({
+    expect(completed.model.turnTiming.byItemId.get("done")).toMatchObject({
       completedAt: at(9),
       durationMs: 8000,
     });

packages/app/src/agent-stream/turn-membership.ts

@@ -1,24 +1,21 @@
+import { continuesTimelineTurn, isTimelineTurnTrigger } from "@getpaseo/protocol/timeline-turn";
 import type { StreamItem } from "@/types/stream";
 
 /**
  * Canonical turn IDs take precedence. Timelines without them retain the legacy
- * user-message boundary rule so old daemons and persisted rows need no rewrite.
+ * trigger boundary rule; missing IDs cannot reconstruct historical batching.
  */
 export function continuesTurn(previous: StreamItem | null, next: StreamItem | null): boolean {
   if (!previous || !next) return false;
-  if (previous.turnId !== undefined && next.turnId !== undefined) {
-    return previous.turnId === next.turnId;
-  }
-  return next.kind !== "user_message";
+  return continuesTimelineTurn(previous.turnId, next.turnId, isTurnTrigger(next));
 }
 
 /**
- * A visible response can span multiple canonical turns when their prompts are
- * system-injected and therefore absent from the Paseo timeline.
+ * Every canonical turn owns its response, including system-triggered runs.
  */
 export function continuesResponse(previous: StreamItem | null, next: StreamItem | null): boolean {
   if (!previous || !next) return false;
-  return continuesTurn(previous, next) || next.kind !== "user_message";
+  return continuesTurn(previous, next);
 }
 
 export function isTurnBoundary(previous: StreamItem | null, next: StreamItem | null): boolean {
@@ -37,3 +34,12 @@ export function startsNewTurn(item: StreamItem, previous: StreamItem | null): bo
 export function belongsToTurn(item: StreamItem, turnId: string | null): boolean {
   return turnId !== null && item.turnId === turnId;
 }
+
+/** Inputs that start a turn when older history has no canonical turn IDs. */
+export function isTurnTrigger(item: StreamItem): boolean {
+  return isTimelineTurnTrigger(
+    item.kind === "tool_call" && item.payload.source === "agent"
+      ? { type: item.kind, ...item.payload.data }
+      : { type: item.kind },
+  );
+}

packages/app/src/agent-stream/view.tsx

@@ -524,8 +524,10 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
           head: effectiveStreamHead ?? EMPTY_STREAM_HEAD,
           transform: transformTimelineItem,
           display: chatDisplay,
+          autoExpandReasoning,
           expandedTurnHostIds,
           isTurnActive,
+          activeTurnId: effectiveTurnPresentation.turnId,
         }),
       [
         presentStream,
@@ -533,8 +535,10 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
         effectiveStreamHead,
         transformTimelineItem,
         chatDisplay,
+        autoExpandReasoning,
         expandedTurnHostIds,
         isTurnActive,
+        effectiveTurnPresentation.turnId,
       ],
     );
     const {
@@ -576,12 +580,12 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
           isTurnActive,
           history: baseRenderModel.history,
           liveHead: baseRenderModel.segments.liveHead,
-          timingByAssistantId: baseRenderModel.turnTiming.byAssistantId,
+          timingByItemId: baseRenderModel.turnTiming.byItemId,
         }),
       [
         baseRenderModel.history,
         baseRenderModel.segments.liveHead,
-        baseRenderModel.turnTiming.byAssistantId,
+        baseRenderModel.turnTiming.byItemId,
         isTurnActive,
         streamRenderStrategy,
       ],
@@ -722,6 +726,7 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
             agentId={agentId}
             messageId={item.messageId}
             message={item.text}
+            sender={item.sender}
             images={item.images}
             attachments={item.attachments}
             timestamp={item.timestamp.getTime()}
@@ -868,10 +873,15 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
       presentation.groupsByHostId.get(hostId),
     );
     const renderToolCallItem = useCallback(
-      (layoutItem: StreamLayoutItem, item: Extract<StreamItem, { kind: "tool_call" }>) => {
+      (
+        layoutItem: StreamLayoutItem,
+        item: Extract<StreamItem, { kind: "tool_call" | "thought" }>,
+      ) => {
         const group = getToolCallGroup(item.id);
         if (!group) {
-          return renderSingleToolCallItem(item, layoutItem.isLastInToolSequence);
+          return item.kind === "thought"
+            ? renderThoughtItem(layoutItem, item)
+            : renderSingleToolCallItem(item, layoutItem.isLastInToolSequence);
         }
         const expanded = expandedToolCallGroupIds.has(group.run.id);
         return (
@@ -884,10 +894,21 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
             {expanded
               ? group.run.calls.map((call, index) => (
                   <React.Fragment key={call.id}>
-                    {renderSingleToolCallItem(
-                      call,
-                      index === group.run.calls.length - 1,
-                      GROUPED_TOOL_CALL_DETAIL_MAX_HEIGHT,
+                    {call.kind === "thought" ? (
+                      <ThoughtSlot
+                        itemId={call.id}
+                        text={call.text}
+                        status={call.status}
+                        isLastInSequence={index === group.run.calls.length - 1}
+                        defaultExpanded
+                        onInlineDetailsExpandedChangeByItemId={setInlineDetailsExpanded}
+                      />
+                    ) : (
+                      renderSingleToolCallItem(
+                        call,
+                        index === group.run.calls.length - 1,
+                        GROUPED_TOOL_CALL_DETAIL_MAX_HEIGHT,
+                      )
                     )}
                   </React.Fragment>
                 ))
@@ -897,6 +918,8 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
       },
       [
         expandedToolCallGroupIds,
+        renderThoughtItem,
+        setInlineDetailsExpanded,
         getToolCallGroup,
         renderSingleToolCallItem,
         setToolCallGroupExpanded,
@@ -914,10 +937,20 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
             return renderAssistantMessageItem(layoutItem, item);
 
           case "thought":
-            return renderThoughtItem(layoutItem, item);
+            return renderToolCallItem(layoutItem, item);
 
           case "tool_call":
-            return renderToolCallItem(layoutItem, item);
+            return (
+              <>
+                {renderToolCallItem(layoutItem, item)}
+                {getCollapsedTurn(item.id) ? (
+                  <TurnSummaryLine
+                    turn={getCollapsedTurn(item.id)!}
+                    onExpandedChange={setTurnExpanded}
+                  />
+                ) : null}
+              </>
+            );
 
           case "notification":
             return <Notification level={item.level} message={item.message} />;
@@ -947,8 +980,9 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
         agentId,
         renderUserMessageItem,
         renderAssistantMessageItem,
-        renderThoughtItem,
         renderToolCallItem,
+        getCollapsedTurn,
+        setTurnExpanded,
         resolvedServerId,
       ],
     );

packages/app/src/agent-stream/web-virtualization.test.ts

@@ -70,6 +70,17 @@ function indexEntries(items: StreamItem[]): IndexedStreamItem[] {
 }
 
 describe("findMountedWindowStart", () => {
+  it("mounts complete autonomous runs and keeps same-run steers together", () => {
+    const items = [
+      { ...userMessage("human", 1), turnId: "first" },
+      { ...assistantMessage("reply", 2), turnId: "first" },
+      { ...toolCall("wake", 3), turnId: "autonomous" },
+      { ...userMessage("steer", 4), turnId: "autonomous" },
+      { ...assistantMessage("done", 5), turnId: "autonomous" },
+    ];
+    expect(findMountedWindowStart({ items, minMountedCount: 1 })).toBe(2);
+  });
+
   it("keeps all items mounted when the chat is below the threshold", () => {
     const items = [userMessage("u1", 1), assistantMessage("a1", 2)];
 

packages/app/src/components/indent-rail.tsx

@@ -3,11 +3,10 @@ import { View, type StyleProp, type ViewStyle } from "react-native";
 import { StyleSheet } from "react-native-unistyles";
 
 /**
- * Collapsed chat rows badge their summary with an icon whose center sits 7px into the content
- * column (`ExpandableBadge` bleeds 13px left, then 1px border, 8px padding, 22px icon). The rail
- * hangs from that center so opened rows read as children of the line that opened them.
+ * Align the rail with the expanded caret's left edge. Keep the content offset fixed so
+ * expanded tool cards stay in place, with a gap between their border and the rail.
  */
-const RAIL_LEFT = 7;
+const RAIL_LEFT = 1;
 const RAIL_WIDTH = 1;
 export const INDENT_RAIL_CONTENT_OFFSET = 21;
 

packages/app/src/components/message.tsx

@@ -1,3 +1,4 @@
+import { MessagePreview, MessageSender } from "@/components/user-message";
 import { useStableEvent } from "@/hooks/use-stable-event";
 import { getAgentAttachmentPillContent } from "@/attachments/attachment-pill-content";
 import { AssistantForkMenu, type AssistantForkTarget } from "@/components/assistant-fork-menu";
@@ -89,6 +90,7 @@ export type { InlinePathTarget } from "@/assistant-file-links";
 export type { AssistantForkTarget };
 
 interface UserMessageProps {
+  sender?: AgentMessage["sender"];
   serverId?: string;
   agentId?: string;
   messageId?: string;
@@ -387,6 +389,7 @@ function UserMessageImagePill({ image, onOpen, accessibilityLabel }: UserMessage
 const MESSAGE_TEXT_DATASET = { messageText: "true" };
 
 export const UserMessage = memo(function UserMessage({
+  sender,
   serverId,
   agentId,
   messageId,
@@ -473,42 +476,45 @@ export const UserMessage = memo(function UserMessage({
         onPointerEnter={handlePointerEnter}
         onPointerLeave={handlePointerLeave}
       >
+        {sender ? <MessageSender sender={sender} serverId={serverId} /> : null}
         <View style={userMessageStylesheet.bubble}>
-          {hasImages ? (
-            <View style={imagePreviewContainerStyle}>
-              {images.map((image) => (
-                <UserMessageImagePill
-                  key={image.id}
-                  image={image}
-                  onOpen={setLightboxMetadata}
-                  accessibilityLabel={t("composer.attachments.openImage")}
-                />
-              ))}
-            </View>
-          ) : null}
-          {hasAttachments ? (
-            <View style={attachmentPreviewContainerStyle}>
-              {attachments.map((attachment, index) => {
-                const content = getAgentAttachmentPillContent(attachment, t);
-                return (
-                  <AttachmentFrame
-                    key={`${attachment.type}:${"number" in attachment ? attachment.number : index}`}
-                  >
-                    <AttachmentLabel
-                      icon={content.icon}
-                      title={content.title}
-                      subtitle={content.subtitle}
-                    />
-                  </AttachmentFrame>
-                );
-              })}
-            </View>
-          ) : null}
-          {hasText ? (
-            <Text selectable style={userMessageStylesheet.text} dataSet={MESSAGE_TEXT_DATASET}>
-              {message}
-            </Text>
-          ) : null}
+          <MessagePreview>
+            {hasImages ? (
+              <View style={imagePreviewContainerStyle}>
+                {images.map((image) => (
+                  <UserMessageImagePill
+                    key={image.id}
+                    image={image}
+                    onOpen={setLightboxMetadata}
+                    accessibilityLabel={t("composer.attachments.openImage")}
+                  />
+                ))}
+              </View>
+            ) : null}
+            {hasAttachments ? (
+              <View style={attachmentPreviewContainerStyle}>
+                {attachments.map((attachment, index) => {
+                  const content = getAgentAttachmentPillContent(attachment, t);
+                  return (
+                    <AttachmentFrame
+                      key={`${attachment.type}:${"number" in attachment ? attachment.number : index}`}
+                    >
+                      <AttachmentLabel
+                        icon={content.icon}
+                        title={content.title}
+                        subtitle={content.subtitle}
+                      />
+                    </AttachmentFrame>
+                  );
+                })}
+              </View>
+            ) : null}
+            {hasText ? (
+              <Text selectable style={userMessageStylesheet.text} dataSet={MESSAGE_TEXT_DATASET}>
+                {message}
+              </Text>
+            ) : null}
+          </MessagePreview>
         </View>
         {hasText ? (
           <View
@@ -541,7 +547,7 @@ export const UserMessage = memo(function UserMessage({
 });
 
 interface AssistantTurnFooterProps {
-  getContent: () => string;
+  getContent?: () => string;
   completedAt?: Date;
   durationMs?: number | null;
   onFork?: (target: AssistantForkTarget) => Promise<void> | void;
@@ -641,10 +647,12 @@ export const AssistantTurnFooter = memo(function AssistantTurnFooter({
 
   return (
     <View style={assistantTurnFooterStylesheet.container}>
-      <TurnCopyButton
-        getContent={getContent}
-        containerStyle={assistantTurnFooterStylesheet.copyButton}
-      />
+      {getContent ? (
+        <TurnCopyButton
+          getContent={getContent}
+          containerStyle={assistantTurnFooterStylesheet.copyButton}
+        />
+      ) : null}
       {canFork ? <AssistantForkMenu onFork={handleFork} /> : null}
       {primaryLabel ? (
         <Pressable

packages/app/src/components/rewind/use-rewind-agent-mutation.ts

@@ -1,3 +1,4 @@
+import { planTimelineTailFetch } from "@/timeline/timeline-sync-plan";
 import { useCallback } from "react";
 import { useTranslation } from "react-i18next";
 import { useMutation } from "@tanstack/react-query";
@@ -42,8 +43,7 @@ export function useRewindAgentMutation(input: UseRewindAgentMutationInput): {
           : undefined;
         if (!input.serverId) throw new Error(t("common.errors.daemonClientUnavailable"));
         await getHostRuntimeStore().fetchAgentTimeline(input.serverId, input.agentId, {
-          direction: "tail",
-          projection: "projected",
+          ...planTimelineTailFetch(),
           ...(cursor ? { cursor: { epoch: cursor.epoch, seq: cursor.endSeq } } : {}),
         });
       }

packages/app/src/components/ui/edge-fade.tsx

@@ -4,9 +4,10 @@ import Svg, { Defs, LinearGradient as SvgLinearGradient, Rect, Stop } from "reac
 import { withUnistyles } from "react-native-unistyles";
 import type { Theme } from "@/styles/theme";
 
-type EdgeFadeBackdrop = "surface0" | "surfaceWorkspace";
+type EdgeFadeBackdrop = "surface0" | "surfaceWorkspace" | "surface3";
 
 const backdropColorMappings: Record<EdgeFadeBackdrop, (theme: Theme) => { color: string }> = {
+  surface3: (theme) => ({ color: theme.colors.surface3 }),
   surface0: (theme) => ({ color: theme.colors.surface0 }),
   surfaceWorkspace: (theme) => ({ color: theme.colors.surfaceWorkspace }),
 };

packages/app/src/components/user-message/index.tsx

@@ -0,0 +1,89 @@
+import { useState, useCallback, useMemo, type ReactNode } from "react";
+import { View, type LayoutChangeEvent } from "react-native";
+import { StyleSheet } from "react-native-unistyles";
+import { useTranslation } from "react-i18next";
+import type { AgentMessage } from "@getpaseo/protocol/agent-message";
+import { Button } from "@/components/ui/button";
+import { EdgeFade } from "@/components/ui/edge-fade";
+import { useProviderIcon } from "@/components/provider-icons";
+import { useSessionStore } from "@/stores/session-store";
+import { navigateToAgent } from "@/utils/navigate-to-agent";
+
+const PREVIEW_HEIGHT = 240;
+
+export function MessagePreview({ children }: { children: ReactNode }) {
+  const { t } = useTranslation();
+  const [expanded, setExpanded] = useState(false);
+  const [height, setHeight] = useState(0);
+  const overflowing = height > PREVIEW_HEIGHT;
+  const measure = useCallback(
+    (event: LayoutChangeEvent) => setHeight(event.nativeEvent.layout.height),
+    [],
+  );
+  const toggle = useCallback(() => setExpanded((value) => !value), []);
+  const accessibilityState = useMemo(() => ({ expanded }), [expanded]);
+  return (
+    <>
+      <View style={!expanded && styles.preview}>
+        <View style={styles.body} onLayout={measure}>
+          {children}
+        </View>
+        {overflowing && !expanded ? (
+          <EdgeFade edge="bottom" solidFraction={0} backdrop="surface3" style={styles.fade} />
+        ) : null}
+      </View>
+      {overflowing ? (
+        <Button
+          variant="ghost"
+          size="sm"
+          style={styles.toggle}
+          accessibilityState={accessibilityState}
+          onPress={toggle}
+        >
+          {t(expanded ? "turnSummary.showLess" : "turnSummary.showMore")}
+        </Button>
+      ) : null}
+    </>
+  );
+}
+
+export function MessageSender({
+  sender,
+  serverId,
+}: {
+  sender: AgentMessage["sender"];
+  serverId?: string;
+}) {
+  const { t } = useTranslation();
+  const host = sender.serverId ?? serverId;
+  const agent = useSessionStore((state) => {
+    const session = host ? state.sessions[host] : undefined;
+    return session?.agents.get(sender.id) ?? session?.agentDetails.get(sender.id);
+  });
+  const ProviderIcon = useProviderIcon(agent?.provider ?? "", host);
+  const renderProviderIcon = useCallback(
+    (color: string) => <ProviderIcon size={16} color={color} />,
+    [ProviderIcon],
+  );
+  const openSender = useCallback(() => {
+    if (host) navigateToAgent({ serverId: host, agentId: sender.id });
+  }, [host, sender.id]);
+  return (
+    <Button
+      variant="ghost"
+      size="sm"
+      leftIcon={renderProviderIcon}
+      disabled={!host}
+      onPress={openSender}
+    >
+      {t("turnSummary.sentBy", { name: agent?.title ?? sender.title ?? sender.id })}
+    </Button>
+  );
+}
+
+const styles = StyleSheet.create((theme) => ({
+  preview: { maxHeight: PREVIEW_HEIGHT, overflow: "hidden" },
+  body: { flexShrink: 0 },
+  toggle: { alignSelf: "flex-start", paddingHorizontal: 0, minHeight: 0, borderWidth: 0 },
+  fade: { position: "absolute", bottom: 0, left: 0, right: 0, height: theme.spacing[12] },
+}));

packages/app/src/composer/index.tsx

@@ -2495,6 +2495,7 @@ function ComposerContentImpl({
                   voiceAgentId={agentId}
                   isAgentRunning={isAgentRunning}
                   defaultSendBehavior={activeSendBehavior}
+                  sendShortcut={appSettings.sendShortcut}
                   onQueue={handleQueue}
                   onSubmitLoadingPress={submitLoadingPressHandler}
                   onKeyPress={handleCommandKeyPress}

packages/app/src/composer/input/input.tsx

@@ -1,3 +1,4 @@
+import type { SendShortcut } from "@/hooks/use-settings";
 import {
   useComposerEditingSession,
   useComposerFullscreen,
@@ -88,6 +89,7 @@ import {
   resolveAlternateSendAction,
   resolveComposerSurfacePresentation,
   resolveComposerSurfaceText,
+  resolveMessageInputEnterAction,
   resolveRetainedSelection,
   runAlternateSendAction,
   runDefaultSendAction,
@@ -96,6 +98,11 @@ import {
 } from "./state";
 
 const DEFAULT_SEND_KEYS: ShortcutKey[][] = [["Enter"]];
+const MOD_ENTER_SEND_KEYS: ShortcutKey[][] = [["mod", "Enter"]];
+
+function resolveSendKeys(sendShortcut: SendShortcut): ShortcutKey[][] {
+  return sendShortcut === "mod-enter" ? MOD_ENTER_SEND_KEYS : DEFAULT_SEND_KEYS;
+}
 const COMPOSER_INPUT_DATASET = { composerInput: "" } as const;
 
 export interface AttachmentMenuItem {
@@ -167,6 +174,7 @@ export interface MessageInputProps {
    *  running. "interrupt" and "steer" send immediately, "queue" queues. Required so the default
    *  lives only in DEFAULT_CLIENT_SETTINGS. */
   defaultSendBehavior: "interrupt" | "steer" | "queue";
+  sendShortcut: SendShortcut;
   /** Callback for queue button when agent is running */
   onQueue?: (payload: MessagePayload) => void;
   /** Optional handler used when submit button is in loading state. */
@@ -402,6 +410,9 @@ interface DesktopKeyPressContext {
   onKeyPressCallback: ((event: ComposerKeyPressEvent) => boolean) | undefined;
   input: ComposerKeyPressEvent["input"];
   submitOnEnter: boolean;
+  sendShortcut: SendShortcut;
+  isAgentRunning: boolean;
+  onQueue: ((payload: MessagePayload) => void) | undefined;
   isSubmitDisabled: boolean;
   isSubmitLoading: boolean;
   disabled: boolean;
@@ -428,12 +439,21 @@ function handleDesktopKeyPressImpl(
   }
 
   if (event.nativeEvent.key !== "Enter") return;
-  if (!ctx.submitOnEnter) return;
-  if (shiftKey) return;
+
+  const action = resolveMessageInputEnterAction({
+    submitOnEnter: ctx.submitOnEnter,
+    sendShortcut: ctx.sendShortcut,
+    shiftKey: shiftKey ?? false,
+    metaKey: metaKey ?? false,
+    ctrlKey: ctrlKey ?? false,
+    isAgentRunning: ctx.isAgentRunning,
+    onQueue: ctx.onQueue,
+  });
+  if (action === null) return;
 
   if (ctx.isSubmitDisabled || ctx.isSubmitLoading || ctx.disabled) return;
   event.preventDefault();
-  if (metaKey || ctrlKey) {
+  if (action === "alternate-send") {
     ctx.handleAlternateSendAction();
     return;
   }
@@ -1112,6 +1132,7 @@ interface ResolvedMessageInputProps {
   voiceAgentId: string | undefined;
   isAgentRunning: boolean;
   defaultSendBehavior: "interrupt" | "steer" | "queue";
+  sendShortcut: SendShortcut;
   onQueue: ((payload: MessagePayload) => void) | undefined;
   onSubmitLoadingPress: (() => void) | undefined;
   onKeyPressCallback: ((event: ComposerKeyPressEvent) => boolean) | undefined;
@@ -1159,6 +1180,7 @@ function resolveMessageInputProps(props: MessageInputProps): ResolvedMessageInpu
     voiceAgentId: props.voiceAgentId,
     isAgentRunning: props.isAgentRunning ?? false,
     defaultSendBehavior: props.defaultSendBehavior,
+    sendShortcut: props.sendShortcut,
     onQueue: props.onQueue,
     onSubmitLoadingPress: props.onSubmitLoadingPress,
     onKeyPressCallback: props.onKeyPress,
@@ -1236,6 +1258,7 @@ export const MessageInput = forwardRef<MessageInputRef, MessageInputProps>(
       voiceAgentId,
       isAgentRunning,
       defaultSendBehavior,
+      sendShortcut,
       onQueue,
       onSubmitLoadingPress,
       onKeyPressCallback,
@@ -1755,6 +1778,9 @@ export const MessageInput = forwardRef<MessageInputRef, MessageInputProps>(
             selectionRef.current,
           ),
           submitOnEnter: shouldSubmitOnEnter,
+          sendShortcut,
+          isAgentRunning,
+          onQueue,
           isSubmitDisabled,
           isSubmitLoading,
           disabled,
@@ -1766,6 +1792,9 @@ export const MessageInput = forwardRef<MessageInputRef, MessageInputProps>(
         shouldHandleWebKeyPress,
         onKeyPressCallback,
         shouldSubmitOnEnter,
+        sendShortcut,
+        isAgentRunning,
+        onQueue,
         isSubmitDisabled,
         isSubmitLoading,
         disabled,
@@ -1980,7 +2009,7 @@ export const MessageInput = forwardRef<MessageInputRef, MessageInputProps>(
           submitLabel={submitLabel}
           submitButtonTestID={submitButtonTestID}
           buttonIconSize={buttonIconSize}
-          sendKeys={DEFAULT_SEND_KEYS}
+          sendKeys={resolveSendKeys(sendShortcut)}
           sendTooltipLabel={sendTooltipLabel}
         />
       ),
@@ -2001,6 +2030,7 @@ export const MessageInput = forwardRef<MessageInputRef, MessageInputProps>(
         submitLabel,
         submitButtonTestID,
         buttonIconSize,
+        sendShortcut,
         sendTooltipLabel,
       ],
     );

packages/app/src/composer/input/state.test.ts

@@ -2,10 +2,12 @@ import { describe, expect, it, vi } from "vitest";
 import {
   applyDictationTranscript,
   computeCanStartDictation,
+  type MessageInputEnterContext,
   resolveActiveSendBehavior,
   resolveComposerSurfacePresentation,
   resolveComposerSurfaceText,
   resolveGlyphRailOffset,
+  resolveMessageInputEnterAction,
   resolveRetainedSelection,
   resolveAlternateSendAction,
   runAlternateSendAction,
@@ -320,6 +322,212 @@ describe("composer send behavior", () => {
   });
 });
 
+describe("resolveMessageInputEnterAction", () => {
+  function enterContext(
+    overrides: Partial<MessageInputEnterContext> = {},
+  ): MessageInputEnterContext {
+    return {
+      submitOnEnter: true,
+      sendShortcut: "enter",
+      shiftKey: false,
+      metaKey: false,
+      ctrlKey: false,
+      isAgentRunning: false,
+      onQueue: () => undefined,
+      ...overrides,
+    };
+  }
+
+  it("returns null for plain, Shift, and modifier Enter when submit on enter is disabled", () => {
+    expect(resolveMessageInputEnterAction(enterContext({ submitOnEnter: false }))).toBeNull();
+    expect(
+      resolveMessageInputEnterAction(enterContext({ submitOnEnter: false, shiftKey: true })),
+    ).toBeNull();
+    expect(
+      resolveMessageInputEnterAction(enterContext({ submitOnEnter: false, metaKey: true })),
+    ).toBeNull();
+    expect(
+      resolveMessageInputEnterAction(enterContext({ submitOnEnter: false, ctrlKey: true })),
+    ).toBeNull();
+  });
+
+  it("still returns null when modifier Enter sends and submit on enter is disabled", () => {
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ sendShortcut: "mod-enter", submitOnEnter: false, metaKey: true }),
+      ),
+    ).toBeNull();
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ sendShortcut: "mod-enter", submitOnEnter: false }),
+      ),
+    ).toBeNull();
+  });
+
+  it("sends on plain Enter when Enter sends", () => {
+    expect(resolveMessageInputEnterAction(enterContext())).toBe("default-send");
+  });
+
+  it("returns null for Shift+Enter when Enter sends", () => {
+    expect(resolveMessageInputEnterAction(enterContext({ shiftKey: true }))).toBeNull();
+  });
+
+  it("returns null for Shift+Cmd+Enter and Shift+Ctrl+Enter so Shift keeps its newline", () => {
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ shiftKey: true, metaKey: true, isAgentRunning: true }),
+      ),
+    ).toBeNull();
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ shiftKey: true, ctrlKey: true, isAgentRunning: true }),
+      ),
+    ).toBeNull();
+  });
+
+  it("sends on Cmd+Enter and Ctrl+Enter while idle even with a queue handler", () => {
+    expect(resolveMessageInputEnterAction(enterContext({ metaKey: true }))).toBe("default-send");
+    expect(resolveMessageInputEnterAction(enterContext({ ctrlKey: true }))).toBe("default-send");
+  });
+
+  it("queues on Cmd+Enter and Ctrl+Enter while the agent is running with a queue handler", () => {
+    expect(
+      resolveMessageInputEnterAction(enterContext({ metaKey: true, isAgentRunning: true })),
+    ).toBe("alternate-send");
+    expect(
+      resolveMessageInputEnterAction(enterContext({ ctrlKey: true, isAgentRunning: true })),
+    ).toBe("alternate-send");
+  });
+
+  it("sends on Cmd+Enter and Ctrl+Enter while running when no queue handler exists", () => {
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ metaKey: true, isAgentRunning: true, onQueue: undefined }),
+      ),
+    ).toBe("default-send");
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ ctrlKey: true, isAgentRunning: true, onQueue: undefined }),
+      ),
+    ).toBe("default-send");
+  });
+
+  it("returns null for plain and Shift+Enter when modifier Enter sends", () => {
+    expect(resolveMessageInputEnterAction(enterContext({ sendShortcut: "mod-enter" }))).toBeNull();
+    expect(
+      resolveMessageInputEnterAction(enterContext({ sendShortcut: "mod-enter", shiftKey: true })),
+    ).toBeNull();
+  });
+
+  it("returns null for Shift+Cmd+Enter and Shift+Ctrl+Enter when modifier Enter sends", () => {
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ sendShortcut: "mod-enter", shiftKey: true, metaKey: true }),
+      ),
+    ).toBeNull();
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ sendShortcut: "mod-enter", shiftKey: true, ctrlKey: true }),
+      ),
+    ).toBeNull();
+  });
+
+  it("sends on Cmd+Enter and Ctrl+Enter while idle when modifier Enter sends", () => {
+    expect(
+      resolveMessageInputEnterAction(enterContext({ sendShortcut: "mod-enter", metaKey: true })),
+    ).toBe("default-send");
+    expect(
+      resolveMessageInputEnterAction(enterContext({ sendShortcut: "mod-enter", ctrlKey: true })),
+    ).toBe("default-send");
+  });
+
+  it("uses the default action on modifier Enter while running when modifier Enter sends", () => {
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ sendShortcut: "mod-enter", metaKey: true, isAgentRunning: true }),
+      ),
+    ).toBe("default-send");
+    expect(
+      resolveMessageInputEnterAction(
+        enterContext({ sendShortcut: "mod-enter", ctrlKey: true, isAgentRunning: true }),
+      ),
+    ).toBe("default-send");
+  });
+
+  describe("composed with the send actions", () => {
+    function actions() {
+      const calls: string[] = [];
+      return {
+        calls,
+        handleSendMessage: () => calls.push("send"),
+        handleQueueMessage: () => calls.push("queue"),
+        onQueue: () => undefined,
+      };
+    }
+
+    function resolveCommandEnterToSendModifierEnter() {
+      return resolveMessageInputEnterAction(
+        enterContext({ sendShortcut: "mod-enter", metaKey: true, isAgentRunning: true }),
+      );
+    }
+
+    it("queues through the default send action when queue behavior is selected and the agent is running", () => {
+      const sendAction = actions();
+
+      expect(resolveCommandEnterToSendModifierEnter()).toBe("default-send");
+
+      runDefaultSendAction({
+        defaultSendBehavior: "queue",
+        isAgentRunning: true,
+        onQueue: sendAction.onQueue,
+        handleSendMessage: sendAction.handleSendMessage,
+        handleQueueMessage: sendAction.handleQueueMessage,
+      });
+
+      expect(sendAction.calls).toEqual(["queue"]);
+    });
+
+    it("sends through the default send action when queue behavior is selected and the agent is idle", () => {
+      const sendAction = actions();
+
+      expect(
+        resolveMessageInputEnterAction(
+          enterContext({ sendShortcut: "mod-enter", metaKey: true, isAgentRunning: false }),
+        ),
+      ).toBe("default-send");
+
+      runDefaultSendAction({
+        defaultSendBehavior: "queue",
+        isAgentRunning: false,
+        onQueue: sendAction.onQueue,
+        handleSendMessage: sendAction.handleSendMessage,
+        handleQueueMessage: sendAction.handleQueueMessage,
+      });
+
+      expect(sendAction.calls).toEqual(["send"]);
+    });
+
+    it.each([{ defaultSendBehavior: "steer" }, { defaultSendBehavior: "interrupt" }] as const)(
+      "sends through the default send action when $defaultSendBehavior behavior is selected and the agent is running",
+      ({ defaultSendBehavior }) => {
+        const sendAction = actions();
+
+        expect(resolveCommandEnterToSendModifierEnter()).toBe("default-send");
+
+        runDefaultSendAction({
+          defaultSendBehavior,
+          isAgentRunning: true,
+          onQueue: sendAction.onQueue,
+          handleSendMessage: sendAction.handleSendMessage,
+          handleQueueMessage: sendAction.handleQueueMessage,
+        });
+
+        expect(sendAction.calls).toEqual(["send"]);
+      },
+    );
+  });
+});
+
 describe("stopRealtimeVoice", () => {
   it("keeps voice mode active when the running agent refuses cancellation", async () => {
     const cancellationError = new Error("active run cancellation was not acknowledged");

packages/app/src/composer/input/state.ts

@@ -1,3 +1,4 @@
+import type { SendShortcut } from "@/hooks/use-settings";
 import type { DaemonClient } from "@getpaseo/client/internal/daemon-client";
 import type { ActiveTurnBehavior } from "@getpaseo/protocol/messages";
 import type { MessagePayload, TextReplacement } from "@/composer/types";
@@ -151,6 +152,29 @@ export function runAlternateSendAction(ctx: SendActionContext): void {
   runDefaultSendAction(ctx);
 }
 
+export type MessageInputEnterAction = "alternate-send" | "default-send";
+
+export interface MessageInputEnterContext {
+  submitOnEnter: boolean;
+  sendShortcut: SendShortcut;
+  shiftKey: boolean;
+  metaKey: boolean;
+  ctrlKey: boolean;
+  isAgentRunning: boolean;
+  onQueue: ((payload: MessagePayload) => void) | undefined;
+}
+
+export function resolveMessageInputEnterAction(
+  ctx: MessageInputEnterContext,
+): MessageInputEnterAction | null {
+  if (!ctx.submitOnEnter) return null;
+  if (ctx.shiftKey) return null;
+  const hasModifier = ctx.metaKey || ctx.ctrlKey;
+  if (ctx.sendShortcut === "mod-enter") return hasModifier ? "default-send" : null;
+  if (hasModifier && ctx.isAgentRunning && ctx.onQueue) return "alternate-send";
+  return "default-send";
+}
+
 export function runMessageInputKeyboardAction(
   action: MessageInputKeyboardActionKind,
   actions: MessageInputKeyboardActions,

packages/app/src/git/diff-document/benchmark-corpus.ts

@@ -0,0 +1,65 @@
+import { readFileSync } from "node:fs";
+import path from "node:path";
+
+/**
+ * The diff shapes the layout benchmarks measure, shared by the node bench
+ * (`model.bench.ts`) and the browser benchmark (`e2e/browser/diff-performance.spec.ts`)
+ * so both report against the same text.
+ */
+export interface BenchmarkCorpusFile {
+  path: string;
+  lines: string[];
+}
+
+function repeatToLength(unit: string, length: number): string {
+  return unit.repeat(Math.ceil(length / unit.length)).slice(0, length);
+}
+
+/** A real source file: short lines, a few with ligature punctuation. */
+export function realCodeCorpusFile(): BenchmarkCorpusFile {
+  const source = readFileSync(path.resolve(__dirname, "../diff-pane.tsx"), "utf8");
+  return { path: "packages/app/src/git/diff-pane.tsx", lines: source.split("\n") };
+}
+
+/** The CHANGELOG shape that once froze the renderer: 42 lines, longest ~600 characters. */
+export function changelogCorpusFile(): BenchmarkCorpusFile {
+  const sentence =
+    "- Fixed an issue where the diff viewer re-measured every line -> on toggle, which made wrapping painfully slow. ";
+  return {
+    path: "CHANGELOG.md",
+    lines: Array.from({ length: 42 }, (_, index) =>
+      repeatToLength(sentence, 200 + ((index * 97) % 398)),
+    ),
+  };
+}
+
+/** Generated TypeScript: ligature punctuation on every line, every tenth line long. */
+export function generatedCodeCorpusFile(lineCount: number): BenchmarkCorpusFile {
+  return {
+    path: "src/generated.ts",
+    lines: Array.from({ length: lineCount }, (_, index) => {
+      const base = `const handler${index} = async (event) => items.filter((item) => item.id !== ${index} && item.kind === "selected");`;
+      return index % 10 === 9 ? repeatToLength(`${base} // `, 320) : base;
+    }),
+  };
+}
+
+/** Serialized data: no ligatures, every line wraps several times. */
+export function jsonCorpusFile(lineCount: number): BenchmarkCorpusFile {
+  return {
+    path: "fixtures/data.json",
+    lines: Array.from({ length: lineCount }, (_, index) =>
+      repeatToLength(`{"id": ${index}, "label": "row ${index}", "tags": ["alpha", "beta"]}, `, 300),
+    ),
+  };
+}
+
+/** A pull-request-sized working diff: one of each shape above. */
+export function pullRequestCorpus(): BenchmarkCorpusFile[] {
+  return [
+    realCodeCorpusFile(),
+    changelogCorpusFile(),
+    generatedCodeCorpusFile(1200),
+    jsonCorpusFile(300),
+  ];
+}

packages/app/src/git/diff-document/model.bench.ts

@@ -0,0 +1,317 @@
+import type { ParsedDiffFile } from "@getpaseo/protocol/messages";
+import { bench, describe } from "vitest";
+import {
+  changelogCorpusFile,
+  generatedCodeCorpusFile,
+  jsonCorpusFile,
+  pullRequestCorpus,
+  realCodeCorpusFile,
+  type BenchmarkCorpusFile,
+} from "./benchmark-corpus";
+import { buildDiffDocumentModel } from "./model";
+import {
+  createAdditiveAdvances,
+  createChunkedAdvanceMeasurer,
+  createChunkedWidthMeasurer,
+  createMeasuredAdvances,
+  requiresShaping,
+} from "./text-measurement";
+import type { BuildDiffDocumentModelInput, TextMeasurer } from "./types";
+
+// The pure layout work the diff surface does when a diff opens or line wrap is
+// toggled, without a browser or Skia. Counts are the backend-independent cost
+// owners (how many strings a shaper has to see), timings are the JS overhead
+// around them:
+//   npx vitest bench --project unit src/git/diff-document/model.bench.ts
+
+const DESKTOP_VIEWPORT = { width: 1400, height: 900 };
+const PHONE_VIEWPORT = { width: 390, height: 800 };
+const CELL_WIDTH = 7.8;
+
+interface MeasurementStats {
+  /** Whole strings handed to the backend. */
+  calls: number;
+  /** Characters inside those strings; canvas and Skia cost scales with this. */
+  characters: number;
+}
+
+interface Backend {
+  measurer: TextMeasurer;
+  stats: MeasurementStats;
+}
+
+function monospaceWidth(text: string): number {
+  let width = 0;
+  for (const character of text) width += character.charCodeAt(0) > 0x2e7f ? 2 : 1;
+  return width * CELL_WIDTH;
+}
+
+function countingMeasure(stats: MeasurementStats): (text: string) => number {
+  return (text) => {
+    stats.calls += 1;
+    stats.characters += text.length;
+    return monospaceWidth(text);
+  };
+}
+
+/** Previous web backend, retained to isolate the cost of width-only probes. */
+function webBackendWithoutWidthProbe(): Backend {
+  const stats: MeasurementStats = { calls: 0, characters: 0 };
+  const measure = countingMeasure(stats);
+  return { stats, measurer: { measure, measureAdvances: createMeasuredAdvances(measure) } };
+}
+
+/**
+ * `createWebTextMeasurer` in surface.web.tsx, with canvas replaced by a counter.
+ * Width-only probes shape one string per chunk, like the native measurer; the
+ * widths are the same sums, in the same order, as the last cumulative advance.
+ */
+function webBackend(): Backend {
+  const stats: MeasurementStats = { calls: 0, characters: 0 };
+  const measure = countingMeasure(stats);
+  const additive = createAdditiveAdvances(measure);
+  return {
+    stats,
+    measurer: {
+      measure,
+      measureAdvances: createMeasuredAdvances(measure),
+      measureWidth: createChunkedWidthMeasurer((graphemes) => {
+        const text = graphemes.join("");
+        return requiresShaping(text) ? measure(text) : (additive(graphemes).at(-1) ?? 0);
+      }),
+    },
+  };
+}
+
+/** `createNativeTextMeasurer` in text.native.ts, with Skia replaced by a counter. */
+function nativeBackend(): Backend {
+  const stats: MeasurementStats = { calls: 0, characters: 0 };
+  const widths = new Map<string, number>();
+  const additive = (graphemes: readonly string[]) => {
+    let advance = 0;
+    return graphemes.map((grapheme) => {
+      let width = widths.get(grapheme);
+      if (width === undefined) {
+        stats.calls += 1;
+        stats.characters += grapheme.length;
+        width = monospaceWidth(grapheme);
+        widths.set(grapheme, width);
+      }
+      return (advance += width);
+    });
+  };
+  const shape = countingMeasure(stats);
+  return {
+    stats,
+    measurer: {
+      measure(text) {
+        return requiresShaping(text) ? shape(text) : (additive([...text]).at(-1) ?? 0);
+      },
+      measureWidth: createChunkedWidthMeasurer((graphemes) => {
+        const text = graphemes.join("");
+        return requiresShaping(text) ? shape(text) : (additive(graphemes).at(-1) ?? 0);
+      }),
+      measureAdvances: createChunkedAdvanceMeasurer({
+        requiresShaping,
+        measureAdditive: additive,
+        measureShaped(graphemes) {
+          shape(graphemes.join(""));
+          let advance = 0;
+          return graphemes.map((grapheme) => (advance += monospaceWidth(grapheme)));
+        },
+      }),
+    },
+  };
+}
+
+function addedFile(file: BenchmarkCorpusFile): ParsedDiffFile {
+  return {
+    path: file.path,
+    isNew: true,
+    isDeleted: false,
+    additions: file.lines.length,
+    deletions: 0,
+    hunks: [
+      {
+        oldStart: 0,
+        oldCount: 0,
+        newStart: 1,
+        newCount: file.lines.length,
+        lines: file.lines.map((content) => ({
+          type: "add" as const,
+          content,
+          tokens: [{ text: content, style: null }],
+        })),
+      },
+    ],
+  };
+}
+
+interface Scenario {
+  name: string;
+  files: ParsedDiffFile[];
+}
+
+const SCENARIOS: Scenario[] = [
+  { name: "real code (diff-pane.tsx)", files: [addedFile(realCodeCorpusFile())] },
+  { name: "changelog (42 long prose lines)", files: [addedFile(changelogCorpusFile())] },
+  { name: "generated code (1200 lines)", files: [addedFile(generatedCodeCorpusFile(1200))] },
+  { name: "json (300 lines x 300 chars)", files: [addedFile(jsonCorpusFile(300))] },
+  { name: "pull request (all of the above)", files: pullRequestCorpus().map(addedFile) },
+];
+
+function input(
+  scenario: Scenario,
+  options: {
+    wrapLines: boolean;
+    viewport: { width: number; height: number };
+    measureText: TextMeasurer;
+  },
+): BuildDiffDocumentModelInput {
+  return {
+    files: scenario.files,
+    collapsedFilePaths: new Set(),
+    layout: "unified",
+    wrapLines: options.wrapLines,
+    viewportWidth: options.viewport.width,
+    typography: { family: "monospace", size: 13, lineHeight: 20 },
+    measureText: options.measureText,
+    palette: {
+      surface: "#000",
+      headerSurface: "#111",
+      border: "#222",
+      foreground: "#fff",
+      foregroundMuted: "#aaa",
+      addition: "green",
+      deletion: "red",
+      additionBackground: "#010",
+      deletionBackground: "#100",
+      emptyBackground: "#111",
+      selection: "blue",
+      headerActiveSurface: "#222",
+      headerBorder: "#333",
+      statusSuccess: "green",
+      statusDanger: "red",
+      statusWarning: "orange",
+      syntax: {},
+    },
+    labels: { binary: "Binary", tooLarge: "Too large" },
+    // What the surfaces pass at scrollTop 0: five viewports tall.
+    materializationWindow: { top: 0, height: options.viewport.height * 5 },
+  };
+}
+
+interface Variant {
+  name: string;
+  wrapLines: boolean;
+  viewport: { width: number; height: number };
+  backend: () => Backend;
+}
+
+const VARIANTS: Variant[] = [
+  {
+    name: "unwrapped desktop | web",
+    wrapLines: false,
+    viewport: DESKTOP_VIEWPORT,
+    backend: webBackend,
+  },
+  {
+    name: "wrapped desktop | web",
+    wrapLines: true,
+    viewport: DESKTOP_VIEWPORT,
+    backend: webBackend,
+  },
+  {
+    name: "wrapped desktop | web without width probe",
+    wrapLines: true,
+    viewport: DESKTOP_VIEWPORT,
+    backend: webBackendWithoutWidthProbe,
+  },
+  {
+    name: "wrapped phone | web",
+    wrapLines: true,
+    viewport: PHONE_VIEWPORT,
+    backend: webBackend,
+  },
+  {
+    name: "unwrapped desktop | native",
+    wrapLines: false,
+    viewport: DESKTOP_VIEWPORT,
+    backend: nativeBackend,
+  },
+  {
+    name: "wrapped desktop | native",
+    wrapLines: true,
+    viewport: DESKTOP_VIEWPORT,
+    backend: nativeBackend,
+  },
+  {
+    name: "wrapped phone | native",
+    wrapLines: true,
+    viewport: PHONE_VIEWPORT,
+    backend: nativeBackend,
+  },
+];
+
+function countModel(scenario: Scenario, variant: Variant) {
+  const { measurer, stats } = variant.backend();
+  const started = performance.now();
+  const model = buildDiffDocumentModel(
+    input(scenario, {
+      wrapLines: variant.wrapLines,
+      viewport: variant.viewport,
+      measureText: measurer,
+    }),
+  );
+  const elapsedMs = performance.now() - started;
+  let materializedCells = 0;
+  let fragments = 0;
+  let graphemes = 0;
+  for (const row of model.rows) {
+    if (row.kind !== "line") continue;
+    for (const cell of row.cells) {
+      if (!cell || cell.fragments.length === 0) continue;
+      materializedCells += 1;
+      fragments += cell.fragments.length;
+      for (const fragment of cell.fragments) graphemes += fragment.graphemes.length;
+    }
+  }
+  const sourceLines = scenario.files.reduce(
+    (count, file) => count + file.hunks.reduce((total, hunk) => total + hunk.lines.length, 0),
+    0,
+  );
+  return {
+    sourceLines,
+    materializedCells,
+    fragments,
+    graphemeObjects: graphemes,
+    measureCalls: stats.calls,
+    measuredCharacters: stats.characters,
+    coldMs: Number(elapsedMs.toFixed(1)),
+  };
+}
+
+const report: Record<string, ReturnType<typeof countModel>> = {};
+for (const scenario of SCENARIOS) {
+  for (const variant of VARIANTS) {
+    report[`${scenario.name} | ${variant.name}`] = countModel(scenario, variant);
+  }
+}
+console.table(report);
+
+for (const scenario of SCENARIOS) {
+  describe(scenario.name, () => {
+    for (const variant of VARIANTS) {
+      if (variant.backend === nativeBackend) continue;
+      bench(variant.name, () => {
+        buildDiffDocumentModel(
+          input(scenario, {
+            wrapLines: variant.wrapLines,
+            viewport: variant.viewport,
+            measureText: variant.backend().measurer,
+          }),
+        );
+      });
+    }
+  });
+}

packages/app/src/git/diff-document/model.test.ts

@@ -10,7 +10,7 @@ import {
   resolveRelayoutScrollTop,
   shouldApplyRelayoutScroll,
 } from "./model";
-import type { BuildDiffDocumentModelInput, TextMeasurer } from "./types";
+import type { BuildDiffDocumentModelInput, DiffCell, TextMeasurer } from "./types";
 
 const measurer: TextMeasurer = { measure: (text) => Array.from(text).length * 10 };
 
@@ -639,17 +639,119 @@ describe("diff document model", () => {
     expect(firstLineCells(last, "b.ts")).toBe(firstLineCells(first, "b.ts"));
   });
 
-  it("keeps wrapped geometry fully measured", () => {
+  it("replaces estimated wrapped heights through reuse and preserves the scroll anchor", () => {
+    const changed = fileWithChangedLine("x".repeat(100));
+    const files = [changed, file("later.ts")];
+    // Deliberately inaccurate M width makes the estimate differ from exact layout.
+    const measureText = {
+      measure: (text: string) => (text === "M" ? 5 : Array.from(text).length * 10),
+    };
+    const options = input({ files, measureText });
+    const first = buildDiffDocumentModel({
+      ...options,
+      materializationWindow: { top: 30, height: 1 },
+    });
+    const eager = buildDiffDocumentModel(options);
+    const exact = buildDiffDocumentModel({ ...options, reuseFrom: [first] });
+    expect(first.height).not.toBe(eager.height);
+    expect(exact.rows).toEqual(eager.rows);
+    expect(exact.height).toBe(eager.height);
+    expect(firstLineCells(exact, changed.path)).toBe(firstLineCells(first, changed.path));
+    const scrollTop = first.files[1]!.bodyTop + 3;
+    const nextScrollTop = resolveRelayoutScrollTop(first, exact, scrollTop);
+    expect(nextScrollTop).toBe(exact.files[1]!.bodyTop + 3);
+    expect(captureScrollAnchor(exact, nextScrollTop)).toEqual(
+      captureScrollAnchor(first, scrollTop),
+    );
+  });
+
+  it("preserves the wrapped source offset when resize leaves the anchor outside the window", () => {
+    const source = file();
+    source.hunks[0]!.lines = Array.from({ length: 200 }, () => ({
+      type: "add" as const,
+      content: "x".repeat(200),
+    }));
+    const options = input({ files: [source], viewportWidth: 500 });
+    const before = buildDiffDocumentModel(options);
+    const scrollTop = before.rows[100]!.top + 36;
+    const anchor = captureScrollAnchor(before, scrollTop)!;
+    expect(anchor).toMatchObject({ kind: "text", cellOffset: 90 });
+    const resizedOptions = { ...options, viewportWidth: 180 };
+    const estimated = buildDiffDocumentModel({
+      ...resizedOptions,
+      materializationWindow: {
+        top: Math.floor(scrollTop / 800) * 800 - 800,
+        height: 2000,
+      },
+    });
+    const estimatedRow = estimated.rows[100]!;
+    expect(estimatedRow.kind === "line" && estimatedRow.cells[0]?.fragments).toEqual([]);
+    const restored = resolveRelayoutScrollTop(before, estimated, scrollTop);
+    const recaptured = captureScrollAnchor(estimated, restored)!;
+    expect(recaptured).toMatchObject({ kind: "text", cellOffset: 78 });
+
+    const materialized = buildDiffDocumentModel({
+      ...resizedOptions,
+      materializationWindow: { top: restored - 800, height: 2000 },
+      reuseFrom: [estimated],
+    });
+    const eager = buildDiffDocumentModel(resizedOptions);
+    const expected = resolveRelayoutScrollTop(before, eager, scrollTop);
+    expect(expected).toBe(28_938);
+    expect(Math.abs(restored - expected)).toBeLessThan(before.lineHeight);
+    expect(resolveRelayoutScrollTop(estimated, materialized, restored)).toBe(expected);
+  });
+
+  it("materializes the relayout anchor even when off-screen height estimates are inaccurate", () => {
+    const source = file();
+    source.hunks[0]!.lines = Array.from({ length: 200 }, () => ({
+      type: "add" as const,
+      content: "x".repeat(200),
+    }));
+    const options = input({ files: [source], viewportWidth: 500 });
+    const before = buildDiffDocumentModel(options);
+    const scrollTop = before.rows[100]!.top + 38;
+    const anchor = captureScrollAnchor(before, scrollTop)!;
+    const resizedOptions = {
+      ...options,
+      viewportWidth: 180,
+      measureText: { measure: (text: string) => (text === "M" ? 5 : text.length * 10) },
+    };
+    const resized = buildDiffDocumentModel({
+      ...resizedOptions,
+      materializationWindow: { top: scrollTop - 800, height: 2000 },
+      materializationAnchor: anchor,
+    });
+    const row = resized.rows[100]!;
+    expect(row.kind === "line" && row.cells[0]!.fragments.length).toBeGreaterThan(0);
+    const restored = resolveRelayoutScrollTop(before, resized, scrollTop);
+    const materialized = buildDiffDocumentModel({
+      ...resizedOptions,
+      materializationWindow: { top: restored - 800, height: 2000 },
+      materializationAnchor: captureScrollAnchor(resized, restored),
+      reuseFrom: [resized],
+    });
+    const nextScrollTop = resolveRelayoutScrollTop(resized, materialized, restored);
+    const nextAnchor = captureScrollAnchor(materialized, nextScrollTop);
+    // Offset 90 belongs to the fragment beginning at 78 after narrowing.
+    expect(nextAnchor).toMatchObject({ kind: "text", cellOffset: 78, viewportDelta: -2 });
+    expect(nextScrollTop).toBe(resolveScrollAnchor(materialized, anchor));
+  });
+
+  it("materializes wrapped text only inside the window", () => {
     const model = buildDiffDocumentModel(
       input({
         files: [file("a.ts"), file("b.ts")],
         wrapLines: true,
-        materializationWindow: { top: 0, height: FILE_HEADER_HEIGHT },
+        materializationWindow: { top: FILE_HEADER_HEIGHT, height: 1 },
       }),
     );
 
     expect(measuredFragments(model, "a.ts")).toBeGreaterThan(0);
-    expect(measuredFragments(model, "b.ts")).toBeGreaterThan(0);
+    expect(measuredFragments(model, "b.ts")).toBe(0);
+    expect(
+      model.rows.filter((row) => row.kind === "line" && row.cells.some(hasFragments)),
+    ).toHaveLength(1);
   });
 });
 
@@ -798,3 +900,7 @@ function reviewActionsWithEditor(
     onDeleteComment() {},
   };
 }
+
+function hasFragments(cell: DiffCell | null): boolean {
+  return cell !== null && cell.fragments.length > 0;
+}

packages/app/src/git/diff-document/model.ts

@@ -154,27 +154,38 @@ function appendReusableFileRows(candidate: {
 }): FileRowsResult {
   const reusedRows = candidate.model.rows.slice(candidate.file.rowStart, candidate.file.rowEnd);
   const retainsRowGeometry =
-    !candidate.input.wrapLines &&
     candidate.model.reviewGeometryKey === candidate.reviewGeometryKey &&
     candidate.file.top === candidate.fileTop &&
     candidate.file.fileIndex === candidate.fileIndex &&
     candidate.file.rowStart === candidate.rows.length;
   let top = candidate.bodyTop;
   for (const reusedRow of reusedRows) {
-    let nextRow = retainsRowGeometry ? reusedRow : repositionReusedRow(reusedRow, candidate, top);
+    let nextRow =
+      retainsRowGeometry && reusedRow.top === top
+        ? reusedRow
+        : repositionReusedRow(reusedRow, candidate, top);
     if (
       nextRow.kind === "line" &&
-      intersectsMaterializationWindow(candidate.input, top, top + nextRow.height) &&
+      (intersectsMaterializationWindow(candidate.input, top, top + nextRow.height) ||
+        containsMaterializationAnchor(candidate.input, candidate.file.path, nextRow.cells)) &&
       nextRow.cells.some((cell) => cell && cell.fragments.length === 0)
     ) {
+      const cells = materializeCells(
+        nextRow.cells,
+        candidate.file.file,
+        candidate.file.gutterWidth,
+        candidate.input,
+      );
       nextRow = {
         ...nextRow,
-        cells: materializeCells(
-          nextRow.cells,
-          candidate.file.file,
-          candidate.file.gutterWidth,
-          candidate.input,
-        ),
+        cells,
+        height:
+          Math.max(
+            candidate.input.typography.lineHeight,
+            ...cells.map(
+              (cell) => (cell?.fragments.length ?? 1) * candidate.input.typography.lineHeight,
+            ),
+          ) + nextRow.reviewHeight,
       };
     }
     candidate.rows.push(nextRow);
@@ -240,6 +251,7 @@ function appendNewFileRows(candidate: {
   const lines = geometryLines(
     lineSources(candidate.file, candidate.input.layout, false),
     candidate.input,
+    candidate.gutterWidth,
   );
   const fileBottom =
     candidate.bodyTop +
@@ -252,8 +264,8 @@ function appendNewFileRows(candidate: {
   let maximumHorizontalOverflow = 0;
   for (const line of lines) {
     const shouldMaterialize =
-      candidate.input.wrapLines ||
-      intersectsMaterializationWindow(candidate.input, top, top + line.height);
+      intersectsMaterializationWindow(candidate.input, top, top + line.height) ||
+      containsMaterializationAnchor(candidate.input, candidate.file.path, line.cells);
     const cells = shouldMaterialize
       ? materializeCells(line.cells, candidate.file, candidate.gutterWidth, candidate.input)
       : line.cells;
@@ -275,7 +287,7 @@ function appendNewFileRows(candidate: {
       candidate.input.typography.lineHeight,
       ...cells.map((cell) => (cell?.fragments.length ?? 1) * candidate.input.typography.lineHeight),
     );
-    const height = textHeight + line.reviewHeight;
+    const height = shouldMaterialize ? textHeight + line.reviewHeight : line.height;
     candidate.rows.push({
       kind: "line",
       index: candidate.rows.length,
@@ -412,13 +424,14 @@ function cellSource(line: SplitDiffDisplayLine | null, includeTokens: boolean):
   };
 }
 
-function geometryCell(source: CellSource): DiffCell {
+function geometryCell(source: CellSource, estimatedWrapColumns: number): DiffCell {
   return {
     type: source.type,
     content: source.content,
     lineNumber: source.lineNumber,
     tokens: [],
     fragments: [],
+    estimatedWrapColumns,
     reviewTarget: source.reviewTarget,
     sourceIdentity: source.sourceIdentity,
   };
@@ -427,20 +440,87 @@ function geometryCell(source: CellSource): DiffCell {
 function geometryLines(
   sources: Array<[CellSource] | [CellSource | null, CellSource | null]>,
   input: BuildDiffDocumentModelInput,
+  gutterWidth: number,
 ): GeometryLine[] {
+  const characterWidth = input.wrapLines ? input.measureText.measure("M") : 0;
   return sources.map((sourceCells) => {
+    const columns = input.wrapLines
+      ? Math.max(
+          1,
+          Math.floor(
+            (input.viewportWidth / sourceCells.length - gutterWidth - CODE_HORIZONTAL_PADDING) /
+              characterWidth,
+          ),
+        )
+      : Infinity;
     const cells = sourceCells.map((source) =>
-      source ? geometryCell(source) : null,
+      source ? geometryCell(source, columns) : null,
     ) as DiffLineRow["cells"];
     const reviewHeight = reviewHeightForCells(cells, input);
     return {
       cells,
       reviewHeight,
-      height: input.typography.lineHeight + reviewHeight,
+      // Unseen wrapped rows use a monospace estimate; materialization replaces
+      // it with the exact fragment count without changing source identity.
+      height:
+        input.typography.lineHeight *
+          Math.max(
+            1,
+            ...cells.map((cell) => {
+              return cell && input.wrapLines
+                ? Math.ceil(estimatedDisplayOffset(cell.content) / columns)
+                : 1;
+            }),
+          ) +
+        reviewHeight,
     };
   });
 }
 
+// Use the same tab expansion and column count for estimated heights and anchors.
+function estimatedDisplayOffset(text: string): number {
+  return text.length + (text.match(/\t/g)?.length ?? 0) * 3;
+}
+
+function estimatedVisualLine(cell: DiffCell, sourceOffset: number): number {
+  return Math.floor(
+    estimatedDisplayOffset(cell.content.slice(0, sourceOffset)) /
+      (cell.estimatedWrapColumns ?? Infinity),
+  );
+}
+
+function estimatedFragment(cell: DiffCell, visualIndex: number, lineHeight: number) {
+  const columns = cell.estimatedWrapColumns ?? Infinity;
+  const lastIndex = Math.max(0, Math.ceil(estimatedDisplayOffset(cell.content) / columns) - 1);
+  const index = Math.min(visualIndex, lastIndex);
+  const displayOffset = index === 0 ? 0 : index * columns;
+  let start = Math.min(displayOffset, cell.content.length);
+  if (cell.content.includes("\t")) {
+    let offset = 0;
+    start = 0;
+    while (start < cell.content.length && offset < displayOffset) {
+      offset += cell.content[start] === "\t" ? 4 : 1;
+      start += 1;
+    }
+  }
+  return { start, top: index * lineHeight };
+}
+
+// A resize can move the anchor outside the old window. Measure that row in the
+// same pass: estimated columns cannot identify exact shaped-text fragments.
+function containsMaterializationAnchor(
+  input: BuildDiffDocumentModelInput,
+  path: string,
+  cells: DiffLineRow["cells"],
+): boolean {
+  const anchor = input.materializationAnchor;
+  return (
+    anchor?.kind === "text" &&
+    anchor.path === path &&
+    cells.some((cell) => cell && sameSourceIdentity(cell.sourceIdentity, anchor.sourceIdentity))
+  );
+}
+
 function intersectsMaterializationWindow(
   input: BuildDiffDocumentModelInput,
   fileTop: number,
@@ -795,17 +875,27 @@ export function captureScrollAnchor(
   }
   const textY = Math.max(0, Math.min(scrollTop - row.top, row.height - row.reviewHeight));
   const visualIndex = Math.max(0, Math.floor(textY / model.lineHeight));
-  let cellIndex = row.cells.findIndex((cell) => Boolean(cell?.fragments[visualIndex]));
+  let cellIndex = row.cells.findIndex(
+    (cell) =>
+      cell &&
+      (cell.fragments.length > 0
+        ? Boolean(cell.fragments[visualIndex])
+        : estimatedFragment(cell, visualIndex, model.lineHeight).top ===
+          visualIndex * model.lineHeight),
+  );
   if (cellIndex < 0) cellIndex = row.cells.findIndex((cell) => cell !== null);
   const cell = row.cells[cellIndex];
   if (!cell) return { kind: "header", path: file.path, viewportDelta: row.top - scrollTop };
-  const fragment = cell.fragments[Math.min(cell.fragments.length - 1, visualIndex)];
-  const anchorY = row.top + (fragment?.top ?? 0);
+  const fragment =
+    cell.fragments.length > 0
+      ? cell.fragments[Math.min(cell.fragments.length - 1, visualIndex)]!
+      : estimatedFragment(cell, visualIndex, model.lineHeight);
+  const anchorY = row.top + fragment.top;
   return {
     kind: "text",
     path: file.path,
     sourceIdentity: cell.sourceIdentity,
-    cellOffset: fragment?.start ?? 0,
+    cellOffset: fragment.start,
     viewportDelta: anchorY - scrollTop,
   };
 }
@@ -831,8 +921,10 @@ export function resolveScrollAnchor(model: DiffDocumentModel, anchor: DiffScroll
   const fragment =
     cell.fragments.find(
       (candidate) => candidate.start <= anchor.cellOffset && anchor.cellOffset < candidate.end,
-    ) ?? cell.fragments.at(-1);
-  return Math.max(0, row.top + (fragment?.top ?? 0) - anchor.viewportDelta);
+    ) ??
+    cell.fragments.at(-1) ??
+    estimatedFragment(cell, estimatedVisualLine(cell, anchor.cellOffset), model.lineHeight);
+  return Math.max(0, row.top + fragment.top - anchor.viewportDelta);
 }
 
 export function resolveRelayoutScrollTop(

packages/app/src/git/diff-document/surface.native.tsx

@@ -38,6 +38,7 @@ import {
 } from "./horizontal-offsets";
 import {
   buildDiffDocumentModel,
+  captureScrollAnchor,
   resolveRelayoutScrollTop,
   retainReusableModels,
   shouldApplyRelayoutScroll,
@@ -138,6 +139,9 @@ export function DiffSurface(props: DiffSurfaceProps) {
         tooLarge: t("workspace.git.diff.tooLarge"),
       },
       materializationWindow: diffMaterializationWindow(fileWindowTop, viewport.height),
+      materializationAnchor: previousModelRef.current
+        ? captureScrollAnchor(previousModelRef.current, scrollTop.get())
+        : null,
       reuseFrom,
     });
     reusableModelRef.current = {
@@ -148,6 +152,7 @@ export function DiffSurface(props: DiffSurfaceProps) {
   }, [
     measurement,
     fileWindowTop,
+    scrollTop,
     props.collapsedFilePaths,
     props.displayPreferences.layout,
     props.displayPreferences.wrapLines,

packages/app/src/git/diff-document/surface.web.tsx

@@ -28,10 +28,20 @@ import {
 } from "./hit-testing";
 import { retainHorizontalOffsetMapForPaths } from "./horizontal-offsets";
 import { HorizontalScroll } from "./horizontal-scroll.web";
-import { buildDiffDocumentModel, FILE_HEADER_HEIGHT, resolveRelayoutScrollTop } from "./model";
+import {
+  buildDiffDocumentModel,
+  captureScrollAnchor,
+  FILE_HEADER_HEIGHT,
+  resolveRelayoutScrollTop,
+} from "./model";
 import { paintWebFileHeader, paintWebViewport } from "./paint.web";
 import { hasPointerDragStarted } from "./pointer-gesture";
-import { createMeasuredAdvances } from "./text-measurement";
+import {
+  createMeasuredAdvances,
+  createAdditiveAdvances,
+  createChunkedWidthMeasurer,
+  requiresShaping,
+} from "./text-measurement";
 import { retainDiffViewport } from "./viewport";
 import type {
   DiffHit,
@@ -183,6 +193,9 @@ export function DiffSurface(props: DiffSurfaceProps) {
         tooLarge: t("workspace.git.diff.tooLarge"),
       },
       materializationWindow: diffMaterializationWindow(fileWindowTop, viewport.height),
+      materializationAnchor: previousModelRef.current
+        ? captureScrollAnchor(previousModelRef.current, scrollTopRef.current)
+        : null,
     });
     return next;
   }, [
@@ -1166,5 +1179,13 @@ function createWebTextMeasurer(typography: DiffTypography): TextMeasurer {
   };
   // Canvas exposes no glyph coverage, so `requiresShaping` alone decides which
   // runs a shaper has to see -- there is no `glyphIds` to fall back on.
-  return { measure, measureAdvances: createMeasuredAdvances((text) => measure(text)) };
+  const additive = createAdditiveAdvances(measure);
+  return {
+    measure,
+    measureAdvances: createMeasuredAdvances(measure),
+    measureWidth: createChunkedWidthMeasurer((graphemes) => {
+      const text = graphemes.join("");
+      return requiresShaping(text) ? measure(text) : (additive(graphemes).at(-1) ?? 0);
+    }),
+  };
 }

packages/app/src/git/diff-document/types.ts

@@ -112,6 +112,8 @@ export interface DiffCell {
   lineNumber: number | null;
   tokens: DiffTokenRun[];
   fragments: DiffFragment[];
+  /** Monospace columns per visual line until this cell is measured. */
+  estimatedWrapColumns?: number;
   reviewTarget: ReviewableDiffTarget | null;
   sourceIdentity: DiffSourceIdentity;
 }
@@ -185,6 +187,8 @@ export interface BuildDiffDocumentModelInput {
   reviewActions?: InlineReviewActions;
   labels: { binary: string; tooLarge: string };
   materializationWindow?: { top: number; height: number };
+  /** Also measure the anchored row so relayout can restore its exact fragment. */
+  materializationAnchor?: DiffScrollAnchor | null;
   /** A geometry-compatible model whose unchanged file measurements may be reused. */
   reuseFrom?: readonly DiffDocumentModel[];
 }

packages/app/src/git/diff-document/workspace-cache.test.ts

@@ -95,6 +95,37 @@ describe("diff document workspace cache", () => {
     expect(stats.calls).toBe(0);
   });
 
+  it("materializes a new anchor when the viewport window is unchanged", () => {
+    const cache = createDiffDocumentWorkspaceCache();
+    const source = diffFile();
+    source.hunks[0]!.lines = Array.from({ length: 100 }, () => ({
+      type: "add" as const,
+      content: "x".repeat(200),
+    }));
+    const { measureText } = countingMeasurer();
+    const input = modelInput([source], measureText, {
+      wrapLines: true,
+      materializationWindow: { top: 30, height: 54 },
+    });
+    const first = cache.buildModel(input);
+    const anchored = cache.buildModel({
+      ...input,
+      materializationAnchor: {
+        kind: "text",
+        path: source.path,
+        sourceIdentity: { hunkIndex: 0, lineIndex: 50, side: "new" },
+        cellOffset: 90,
+        viewportDelta: -2,
+      },
+    });
+    const firstRow = first.rows[50]!;
+    const anchoredRow = anchored.rows[50]!;
+    expect(firstRow.kind === "line" && firstRow.cells[0]!.fragments.length).toBe(0);
+    expect(anchoredRow.kind === "line" && anchoredRow.cells[0]!.fragments.length).toBeGreaterThan(
+      0,
+    );
+  });
+
   it("retains text cells for unchanged files when another file changes", () => {
     const cache = createDiffDocumentWorkspaceCache();
     const { measureText } = countingMeasurer();

packages/app/src/git/diff-document/workspace-cache.tsx

@@ -128,7 +128,9 @@ function exactModelKey(input: Omit<BuildDiffDocumentModelInput, "reuseFrom">): s
   const materializationWindow = input.materializationWindow
     ? [input.materializationWindow.top, input.materializationWindow.height]
     : null;
-  return JSON.stringify([collapsedFilePaths, reviewGeometry, materializationWindow]);
+  const anchor = input.materializationAnchor;
+  const anchoredRow = anchor?.kind === "text" ? [anchor.path, anchor.sourceIdentity] : null;
+  return JSON.stringify([collapsedFilePaths, reviewGeometry, materializationWindow, anchoredRow]);
 }
 
 function typographyKey(typography: DiffTypography): string {

packages/app/src/hooks/use-agent-initialization.test.ts

@@ -78,6 +78,7 @@ describe("ensureAgentIsInitialized", () => {
           cursor: { epoch: "epoch-1", seq: 42 },
           limit: TIMELINE_FETCH_PAGE_SIZE,
           projection: "projected",
+          wholeTurns: true,
         },
       },
     ]);
@@ -105,6 +106,7 @@ describe("ensureAgentIsInitialized", () => {
           direction: "tail",
           limit: TIMELINE_FETCH_PAGE_SIZE,
           projection: "projected",
+          wholeTurns: true,
         },
       },
     ]);
@@ -148,6 +150,7 @@ describe("ensureAgentIsInitialized", () => {
           direction: "tail",
           limit: TIMELINE_FETCH_PAGE_SIZE,
           projection: "projected",
+          wholeTurns: true,
         },
       },
     ]);
@@ -192,6 +195,7 @@ describe("ensureAgentIsInitialized", () => {
           cursor: { epoch: "epoch-1", seq: 12 },
           limit: TIMELINE_FETCH_PAGE_SIZE,
           projection: "projected",
+          wholeTurns: true,
         },
       },
     ]);
@@ -283,6 +287,7 @@ describe("refreshAgent", () => {
           direction: "tail",
           limit: TIMELINE_FETCH_PAGE_SIZE,
           projection: "projected",
+          wholeTurns: true,
         },
       },
     ]);

packages/app/src/hooks/use-load-older-agent-history.test.ts

@@ -152,6 +152,7 @@ describe("loadOlderAgentHistory", () => {
           cursor: { epoch: "epoch-1", seq: 10 },
           limit: TIMELINE_FETCH_PAGE_SIZE,
           projection: "projected",
+          wholeTurns: true,
         },
       },
     ]);

packages/app/src/hooks/use-settings/index.ts

@@ -49,6 +49,7 @@ import {
   type KeyValueStorage,
   type ReleaseChannel,
   type SendBehavior,
+  type SendShortcut,
   type ServiceUrlBehavior,
   type Settings,
   type SidebarWorkspaceTrailing,
@@ -93,6 +94,7 @@ export type {
   KeyValueStorage,
   ReleaseChannel,
   SendBehavior,
+  SendShortcut,
   ServiceUrlBehavior,
   Settings,
   SettingsDeps,

packages/app/src/hooks/use-settings/storage.test.ts

@@ -227,6 +227,39 @@ describe("loadAppSettingsFromStorage", () => {
     expect(result.chatOutlineEnabled).toBe(false);
   });
 
+  it("uses Enter to send by default", async () => {
+    const deps = makeDeps();
+
+    const result = await loadAppSettingsFromStorage(deps);
+
+    expect(result.sendShortcut).toBe("enter");
+    expect(DEFAULT_CLIENT_SETTINGS.sendShortcut).toBe("enter");
+  });
+
+  it("loads the modifier Enter send preference", async () => {
+    const deps = makeDeps({
+      storage: createInMemoryKeyValueStorage({
+        [APP_SETTINGS_KEY]: JSON.stringify({ sendShortcut: "mod-enter" }),
+      }),
+    });
+
+    const result = await loadAppSettingsFromStorage(deps);
+
+    expect(result.sendShortcut).toBe("mod-enter");
+  });
+
+  it("falls back to Enter when the stored send shortcut is invalid", async () => {
+    const deps = makeDeps({
+      storage: createInMemoryKeyValueStorage({
+        [APP_SETTINGS_KEY]: JSON.stringify({ sendShortcut: "yes" }),
+      }),
+    });
+
+    const result = await loadAppSettingsFromStorage(deps);
+
+    expect(result.sendShortcut).toBe("enter");
+  });
+
   it("defaults sidebar navigation items to an empty preference list", async () => {
     const deps = makeDeps();
 

packages/app/src/hooks/use-settings/storage.ts

@@ -33,6 +33,8 @@ import { migrateAppSettings } from "./migrations";
 export { APP_SETTINGS_KEY } from "./keys";
 export const APP_SETTINGS_QUERY_KEY = ["app-settings"];
 
+export type SendShortcut = "enter" | "mod-enter";
+
 export type SendBehavior = ActiveTurnBehavior | "queue";
 export type ReleaseChannel = "stable" | "beta";
 export type ServiceUrlBehavior = "ask" | "in-app" | "external";
@@ -104,6 +106,7 @@ export interface AppSettings {
   chatDisplay: ChatDisplay;
   chatOutlineEnabled: boolean;
   vimKeybindings: boolean;
+  sendShortcut: SendShortcut;
   filePanelAssociations: Record<string, string>;
   /** Desktop-only preferences for implicit opens into the ordinary side pane. */
   openInSidePane: OpenInSidePanePreferences;
@@ -160,6 +163,7 @@ export const DEFAULT_CLIENT_SETTINGS: AppSettings = {
   chatDisplay: "collapseTurns",
   chatOutlineEnabled: true,
   vimKeybindings: false,
+  sendShortcut: "enter",
   filePanelAssociations: {},
   openInSidePane: DEFAULT_OPEN_IN_SIDE_PANE_PREFERENCES,
   pullRequestOpenLocation: "explorer",
@@ -264,6 +268,7 @@ const StoredAppSettingsSchema = z
     compactToolCalls: z.boolean().optional().catch(undefined),
     chatOutlineEnabled: z.boolean().catch(true),
     vimKeybindings: z.boolean().catch(false),
+    sendShortcut: z.enum(["enter", "mod-enter"]).catch("enter"),
     filePanelAssociations: z.record(z.string(), z.string()).catch({}),
     openInSidePane: z
       .object({

packages/app/src/i18n/resources/ar.ts

@@ -2018,12 +2018,13 @@ export const ar: TranslationResources = {
     output: "الإخراج",
   },
   turnSummary: {
-    messages: {
-      one: "كتب {{count}} رسالة",
-      other: "كتب {{count}} رسائل",
-    },
+    details: "عرض تفاصيل الجولة",
+    sentBy: "أرسلها {{name}}",
+    showMore: "عرض المزيد",
+    showLess: "عرض أقل",
   },
   toolCallGroup: {
+    thought: "فكّر",
     editedFiles: {
       one: "حرّر {{count}} ملفًا",
       other: "حرّر {{count}} ملفات",
@@ -2369,12 +2370,25 @@ export const ar: TranslationResources = {
             "عند تشغيل الوكيل، يوجّه Enter الجولة النشطة. يضيف Command/Ctrl+Enter إلى قائمة الانتظار.",
           queue: "عند تشغيل الوكيل، يضيف Enter إلى قائمة الانتظار. Command/Ctrl+Enter يرسل.",
         },
+        commandEnterDescriptions: {
+          interrupt: "عند تشغيل الوكيل، يوقف {{modifier}}+Enter التشغيل. يُدرج Enter سطرًا جديدًا.",
+          steer: "عند تشغيل الوكيل، يوجّه {{modifier}}+Enter الجولة النشطة. يُدرج Enter سطرًا جديدًا.",
+          queue:
+            "عند تشغيل الوكيل، يضيف {{modifier}}+Enter إلى قائمة الانتظار. يُدرج Enter سطرًا جديدًا.",
+        },
         options: {
           interrupt: "مقاطعة",
           steer: "توجيه",
           queue: "طابور",
         },
       },
+      sendShortcut: {
+        label: "اختصار الإرسال",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "بسأل",

packages/app/src/i18n/resources/en.ts

@@ -2043,12 +2043,13 @@ export const en = {
     output: "Output",
   },
   turnSummary: {
-    messages: {
-      one: "wrote {{count}} message",
-      other: "wrote {{count}} messages",
-    },
+    details: "View turn details",
+    sentBy: "Sent by {{name}}",
+    showMore: "Show more",
+    showLess: "Show less",
   },
   toolCallGroup: {
+    thought: "Thought",
     editedFiles: {
       one: "edited {{count}} file",
       other: "edited {{count}} files",
@@ -2457,12 +2458,26 @@ export const en = {
             "When the agent is running, Enter steers the active turn. Command/Ctrl+Enter queues.",
           queue: "When the agent is running, Enter queues. Command/Ctrl+Enter submits.",
         },
+        commandEnterDescriptions: {
+          interrupt:
+            "When the agent is running, {{modifier}}+Enter interrupts. Enter inserts a new line.",
+          steer:
+            "When the agent is running, {{modifier}}+Enter steers the active turn. Enter inserts a new line.",
+          queue: "When the agent is running, {{modifier}}+Enter queues. Enter inserts a new line.",
+        },
         options: {
           interrupt: "Interrupt",
           steer: "Steer",
           queue: "Queue",
         },
       },
+      sendShortcut: {
+        label: "Send shortcut",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "Ask",

packages/app/src/i18n/resources/es.ts

@@ -2066,12 +2066,13 @@ export const es: TranslationResources = {
     output: "Producción",
   },
   turnSummary: {
-    messages: {
-      one: "escribió {{count}} mensaje",
-      other: "escribió {{count}} mensajes",
-    },
+    details: "Ver detalles del turno",
+    sentBy: "Enviado por {{name}}",
+    showMore: "Mostrar más",
+    showLess: "Mostrar menos",
   },
   toolCallGroup: {
+    thought: "Razonó",
     editedFiles: {
       one: "editó {{count}} archivo",
       other: "editó {{count}} archivos",
@@ -2384,12 +2385,27 @@ export const es: TranslationResources = {
           queue:
             "Cuando el agente se está ejecutando, Enter pone en cola. Command/Ctrl+Enter envía.",
         },
+        commandEnterDescriptions: {
+          interrupt:
+            "Cuando el agente se está ejecutando, {{modifier}}+Enter interrumpe. Enter inserta una línea nueva.",
+          steer:
+            "Cuando el agente se está ejecutando, {{modifier}}+Enter dirige el turno activo. Enter inserta una línea nueva.",
+          queue:
+            "Cuando el agente se está ejecutando, {{modifier}}+Enter pone en cola. Enter inserta una línea nueva.",
+        },
         options: {
           interrupt: "Interrumpir",
           steer: "Dirigir",
           queue: "Cola",
         },
       },
+      sendShortcut: {
+        label: "Atajo de envío",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "Preguntar",

packages/app/src/i18n/resources/fr.ts

@@ -2065,12 +2065,13 @@ export const fr: TranslationResources = {
     output: "Sortie",
   },
   turnSummary: {
-    messages: {
-      one: "{{count}} message écrit",
-      other: "{{count}} messages écrits",
-    },
+    details: "Voir les détails du tour",
+    sentBy: "Envoyé par {{name}}",
+    showMore: "Afficher plus",
+    showLess: "Afficher moins",
   },
   toolCallGroup: {
+    thought: "Réfléchi",
     editedFiles: {
       one: "{{count}} fichier modifié",
       other: "{{count}} fichiers modifiés",
@@ -2383,12 +2384,27 @@ export const fr: TranslationResources = {
           queue:
             "Quand l’agent est en cours d’exécution, Entrée met en file d’attente. Cmd/Ctrl+Entrée envoie.",
         },
+        commandEnterDescriptions: {
+          interrupt:
+            "Lorsque l'agent est en cours d'exécution, {{modifier}}+Entrée interrompt. Entrée insère une nouvelle ligne.",
+          steer:
+            "Lorsque l'agent est en cours d'exécution, {{modifier}}+Entrée oriente le tour actif. Entrée insère une nouvelle ligne.",
+          queue:
+            "Lorsque l'agent est en cours d'exécution, {{modifier}}+Entrée met en file d'attente. Entrée insère une nouvelle ligne.",
+        },
         options: {
           interrupt: "Interrompre",
           steer: "Réorienter",
           queue: "File d’attente",
         },
       },
+      sendShortcut: {
+        label: "Raccourci d’envoi",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "Demander",

packages/app/src/i18n/resources/ja.ts

@@ -2038,12 +2038,13 @@ export const ja: TranslationResources = {
     output: "出力",
   },
   turnSummary: {
-    messages: {
-      one: "{{count}}件のメッセージを送信",
-      other: "{{count}}件のメッセージを送信",
-    },
+    details: "ターンの詳細を表示",
+    sentBy: "{{name}} から送信",
+    showMore: "もっと見る",
+    showLess: "折りたたむ",
   },
   toolCallGroup: {
+    thought: "思考",
     editedFiles: {
       one: "{{count}}個のファイルを編集",
       other: "{{count}}個のファイルを編集",
@@ -2353,12 +2354,25 @@ export const ja: TranslationResources = {
             "エージェント実行中、Enterで現在のターンに指示を送ります。Command/Ctrl+Enterでキューに追加。",
           queue: "エージェント実行中、Enterでキューに追加します。Command/Ctrl+Enterで送信。",
         },
+        commandEnterDescriptions: {
+          interrupt: "エージェント実行中、{{modifier}}+Enterで中断します。Enterで改行します。",
+          steer:
+            "エージェント実行中、{{modifier}}+Enterで現在のターンに指示を送ります。Enterで改行します。",
+          queue: "エージェント実行中、{{modifier}}+Enterでキューに追加します。Enterで改行します。",
+        },
         options: {
           interrupt: "中断",
           steer: "指示",
           queue: "キュー",
         },
       },
+      sendShortcut: {
+        label: "送信ショートカット",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "確認する",

packages/app/src/i18n/resources/ko.ts

@@ -2028,12 +2028,13 @@ export const ko: TranslationResources = {
     output: "출력",
   },
   turnSummary: {
-    messages: {
-      one: "{{count}} 메시지를 작성했습니다.",
-      other: "{{count}} 메시지를 작성했습니다.",
-    },
+    details: "턴 세부 정보 보기",
+    sentBy: "{{name}}이(가) 보냄",
+    showMore: "더 보기",
+    showLess: "접기",
   },
   toolCallGroup: {
+    thought: "생각함",
     editedFiles: {
       one: "{{count}} 파일을 편집했습니다.",
       other: "{{count}} 파일을 편집했습니다.",
@@ -2344,12 +2345,27 @@ export const ko: TranslationResources = {
           queue:
             "에이전트가 실행 중일 때 Enter는 대기열에 추가합니다. Command/Ctrl+Enter는 제출합니다.",
         },
+        commandEnterDescriptions: {
+          interrupt:
+            "에이전트가 실행 중일 때 {{modifier}}+Enter는 중단합니다. Enter는 줄바꿈합니다.",
+          steer:
+            "에이전트가 실행 중일 때 {{modifier}}+Enter는 현재 턴에 지시합니다. Enter는 줄바꿈합니다.",
+          queue:
+            "에이전트가 실행 중일 때 {{modifier}}+Enter는 대기열에 추가합니다. Enter는 줄바꿈합니다.",
+        },
         options: {
           interrupt: "중단",
           steer: "지시",
           queue: "대기열",
         },
       },
+      sendShortcut: {
+        label: "전송 단축키",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "물어보기",

packages/app/src/i18n/resources/pt-BR.ts

@@ -2051,12 +2051,13 @@ export const ptBR: TranslationResources = {
     output: "Saída",
   },
   turnSummary: {
-    messages: {
-      one: "escreveu {{count}} mensagem",
-      other: "escreveu {{count}} mensagens",
-    },
+    details: "Ver detalhes do turno",
+    sentBy: "Enviado por {{name}}",
+    showMore: "Mostrar mais",
+    showLess: "Mostrar menos",
   },
   toolCallGroup: {
+    thought: "Pensou",
     editedFiles: {
       one: "editou {{count}} arquivo",
       other: "editou {{count}} arquivos",
@@ -2367,12 +2368,27 @@ export const ptBR: TranslationResources = {
             "Quando o agente está em execução, Enter orienta o turno ativo. Command/Ctrl+Enter enfileira.",
           queue: "Quando o agente está em execução, Enter enfileira. Command/Ctrl+Enter envia.",
         },
+        commandEnterDescriptions: {
+          interrupt:
+            "Quando o agente está em execução, {{modifier}}+Enter interrompe. Enter insere uma nova linha.",
+          steer:
+            "Quando o agente está em execução, {{modifier}}+Enter orienta o turno ativo. Enter insere uma nova linha.",
+          queue:
+            "Quando o agente está em execução, {{modifier}}+Enter enfileira. Enter insere uma nova linha.",
+        },
         options: {
           interrupt: "Interromper",
           steer: "Orientar",
           queue: "Fila",
         },
       },
+      sendShortcut: {
+        label: "Atalho de envio",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "Perguntar",

packages/app/src/i18n/resources/ru.ts

@@ -2051,12 +2051,13 @@ export const ru: TranslationResources = {
     output: "Выходные данные",
   },
   turnSummary: {
-    messages: {
-      one: "написано {{count}} сообщение",
-      other: "написаны сообщения ({{count}})",
-    },
+    details: "Показать подробности хода",
+    sentBy: "Отправлено агентом {{name}}",
+    showMore: "Показать больше",
+    showLess: "Свернуть",
   },
   toolCallGroup: {
+    thought: "Обдумал",
     editedFiles: {
       one: "изменён {{count}} файл",
       other: "изменены файлы ({{count}})",
@@ -2370,12 +2371,27 @@ export const ru: TranslationResources = {
           queue:
             "Когда агент работает, Enter ставит сообщение в очередь, а Command/Ctrl+Enter отправляет его.",
         },
+        commandEnterDescriptions: {
+          interrupt:
+            "Когда агент работает, {{modifier}}+Enter прерывает его работу, а Enter вставляет новую строку.",
+          steer:
+            "Когда агент работает, {{modifier}}+Enter дополняет текущий ответ новым указанием, а Enter вставляет новую строку.",
+          queue:
+            "Когда агент работает, {{modifier}}+Enter ставит сообщение в очередь, а Enter вставляет новую строку.",
+        },
         options: {
           interrupt: "Прерывать",
           steer: "Направить",
           queue: "Поставить в очередь",
         },
       },
+      sendShortcut: {
+        label: "Сочетание клавиш для отправки",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "Спрашивать",

packages/app/src/i18n/resources/zh-CN.ts

@@ -1996,12 +1996,13 @@ export const zhCN: TranslationResources = {
     output: "输出",
   },
   turnSummary: {
-    messages: {
-      one: "写了 {{count}} 条消息",
-      other: "写了 {{count}} 条消息",
-    },
+    details: "查看轮次详情",
+    sentBy: "由 {{name}} 发送",
+    showMore: "展开",
+    showLess: "收起",
   },
   toolCallGroup: {
+    thought: "已思考",
     editedFiles: {
       one: "编辑了 {{count}} 个文件",
       other: "编辑了 {{count}} 个文件",
@@ -2308,12 +2309,24 @@ export const zhCN: TranslationResources = {
           steer: "Agent 运行时，Enter 会引导当前回合。Command/Ctrl+Enter 会排队。",
           queue: "Agent 运行时，Enter 会排队。Command/Ctrl+Enter 会提交。",
         },
+        commandEnterDescriptions: {
+          interrupt: "Agent 运行时，{{modifier}}+Enter 会中断。Enter 会插入换行。",
+          steer: "Agent 运行时，{{modifier}}+Enter 会引导当前回合。Enter 会插入换行。",
+          queue: "Agent 运行时，{{modifier}}+Enter 会排队。Enter 会插入换行。",
+        },
         options: {
           interrupt: "中断",
           steer: "引导",
           queue: "排队",
         },
       },
+      sendShortcut: {
+        label: "发送快捷键",
+        options: {
+          enter: "Enter",
+          "mod-enter": "{{modifier}}+Enter",
+        },
+      },
       serviceUrls: {
         options: {
           ask: "询问",

packages/app/src/runtime/replica-cache/index.test.ts

@@ -306,6 +306,21 @@ async function expectLegacyWorkspaceRefresh({
 }
 
 describe("ReplicaCache", () => {
+  it("persists the complete newest turn beyond the cache item target", async () => {
+    const storage = new MemoryStorage();
+    const writer = createCache(storage);
+    const items = Array.from({ length: 60 }, (_, index) => ({
+      ...timelineItem(`item-${index}`),
+      id: `item-${index}`,
+      turnId: "long-run",
+    }));
+    writer.commitTimeline(SERVER_ID, "agent-1", { ...timeline(), items });
+    await writer.flush();
+    const restored = await createCache(storage).readTimeline(SERVER_ID, "agent-1");
+    expect(restored?.items.map((item) => item.id)).toEqual(items.map((item) => item.id));
+    expect(restored?.range).toBeNull();
+  });
+
   it("preserves workspace sorting timestamps across cache reopen", async () => {
     const storage = new MemoryStorage();
     const writer = createCache(storage);

packages/app/src/runtime/replica-cache/index.ts

@@ -1,3 +1,4 @@
+import { findMountedWindowStart } from "@/agent-stream/history-window";
 import { z } from "zod";
 import {
   AgentStatusSchema,
@@ -766,7 +767,14 @@ function serializeTimeline(timeline: CachedTimeline): StoredTimeline | null {
   const canonicalItems = timeline.items.filter(
     (item) => item.kind !== "user_message" || !isUnreconciledLocalUserMessage(item),
   );
-  const items = canonicalItems.map(serializeTimelineItem).filter((item) => item !== null);
+  const start = findMountedWindowStart({
+    items: canonicalItems,
+    minMountedCount: MAX_TIMELINE_ITEMS,
+  });
+  const items = canonicalItems
+    .slice(start)
+    .map(serializeTimelineItem)
+    .filter((item) => item !== null);
   const range = timeline.range;
   const canPersistCoverage =
     range !== null &&
@@ -783,7 +791,7 @@ function serializeTimeline(timeline: CachedTimeline): StoredTimeline | null {
     canonicalItems.some((item) => item.timelineCursor?.seq === range.endSeq);
   return {
     agentId: timeline.agentId,
-    items: items.slice(-MAX_TIMELINE_ITEMS),
+    items,
     range: canPersistCoverage
       ? { epoch: range.epoch, startSeq: range.startSeq, endSeq: range.endSeq }
       : null,

packages/app/src/screens/settings/general/sending-section.tsx

@@ -1,13 +1,17 @@
 import { useCallback, useMemo } from "react";
 import { useTranslation } from "react-i18next";
 import { SettingsCard, SettingsSection, SettingsSelect } from "@/components/settings";
-import { useAppSettings, type SendBehavior } from "@/hooks/use-settings";
+import { useAppSettings, type SendShortcut, type SendBehavior } from "@/hooks/use-settings";
+import { useKeyboardShortcutsAvailable } from "@/keyboard/availability";
+import { getShortcutOs } from "@/utils/shortcut-platform";
 
 const SEND_BEHAVIORS: readonly SendBehavior[] = ["interrupt", "steer", "queue"];
 
 export function SendingSection() {
   const { t } = useTranslation();
   const { settings, updateSettings } = useAppSettings();
+  const shortcutsAvailable = useKeyboardShortcutsAvailable();
+  const modifier = getShortcutOs() === "mac" ? "⌘" : "Ctrl";
   const options = useMemo(
     () =>
       SEND_BEHAVIORS.map((value) => ({
@@ -20,12 +24,37 @@ export function SendingSection() {
     (sendBehavior: SendBehavior) => void updateSettings({ sendBehavior }),
     [updateSettings],
   );
+  const shortcutOptions = useMemo(
+    () =>
+      (["enter", "mod-enter"] as const).map((value) => ({
+        value,
+        label: t(`settings.general.sendShortcut.options.${value}`, { modifier }),
+      })),
+    [t, modifier],
+  );
+  const changeSendShortcut = useCallback(
+    (sendShortcut: SendShortcut) => void updateSettings({ sendShortcut }),
+    [updateSettings],
+  );
   return (
     <SettingsSection title={t("settings.general.sending")}>
       <SettingsCard>
+        {shortcutsAvailable ? (
+          <SettingsSelect
+            label={t("settings.general.sendShortcut.label")}
+            value={settings.sendShortcut}
+            options={shortcutOptions}
+            onValueChange={changeSendShortcut}
+          />
+        ) : null}
         <SettingsSelect
           label={t("settings.general.defaultSend.label")}
-          hint={t(`settings.general.defaultSend.descriptions.${settings.sendBehavior}`)}
+          hint={t(
+            shortcutsAvailable && settings.sendShortcut === "mod-enter"
+              ? `settings.general.defaultSend.commandEnterDescriptions.${settings.sendBehavior}`
+              : `settings.general.defaultSend.descriptions.${settings.sendBehavior}`,
+            { modifier },
+          )}
           value={settings.sendBehavior}
           options={options}
           onValueChange={change}

packages/app/src/screens/workspace/workspace-screen.tsx

@@ -1,3 +1,4 @@
+import { planTimelineTailFetch } from "@/timeline/timeline-sync-plan";
 import { useHostFeature } from "@/runtime/host-features";
 import {
   AssistantFileLinkResolverProvider,
@@ -2179,8 +2180,7 @@ function WorkspaceScreenContent({
         const sessionState = useSessionStore.getState().sessions[normalizedServerId];
         const currentCursor = sessionState?.agentTimelineCursor.get(agentId);
         await getHostRuntimeStore().fetchAgentTimeline(normalizedServerId, agentId, {
-          direction: "tail",
-          projection: "projected",
+          ...planTimelineTailFetch(),
           ...(currentCursor
             ? { cursor: { epoch: currentCursor.epoch, seq: currentCursor.endSeq } }
             : {}),

packages/app/src/terminal/runtime/terminal-glyph-rendering.browser.test.ts

@@ -0,0 +1,203 @@
+import "@xterm/xterm/css/xterm.css";
+import { page } from "vitest/browser";
+import { afterEach, expect, it } from "vitest";
+import type { Terminal } from "@xterm/xterm";
+import { encodeTerminalOutput, TerminalEmulatorRuntime } from "./terminal-emulator-runtime";
+
+interface TerminalView {
+  root: HTMLDivElement;
+  host: HTMLDivElement;
+  runtime: TerminalEmulatorRuntime;
+  terminal: Terminal;
+}
+
+interface RowImage {
+  width: number;
+  height: number;
+  pixels: Uint8ClampedArray;
+}
+
+const views: TerminalView[] = [];
+const header = "HEADER_0123456789 한글 日本語";
+
+function mountTerminal(left: number): TerminalView {
+  const root = document.createElement("div");
+  Object.assign(root.style, {
+    position: "fixed",
+    left: `${left}px`,
+    top: "0",
+    width: "440px",
+    height: "360px",
+    overflow: "hidden",
+  });
+  const host = document.createElement("div");
+  Object.assign(host.style, { width: "100%", height: "100%" });
+  root.appendChild(host);
+  document.body.appendChild(root);
+  const runtime = new TerminalEmulatorRuntime();
+  runtime.mount({
+    root,
+    host,
+    initialSnapshot: null,
+    scrollback: 1000,
+    fontFamily: "monospace",
+    fontSize: 16,
+    theme: { background: "#101010", foreground: "#eeeeee", cursor: "#eeeeee" },
+  });
+  const terminal = window.__paseoTerminal;
+  if (!terminal) throw new Error("Terminal did not mount");
+  const view = { root, host, runtime, terminal };
+  views.push(view);
+  return view;
+}
+
+function write(view: TerminalView, text: string): Promise<void> {
+  return new Promise((resolve) => {
+    view.runtime.write({ data: encodeTerminalOutput(text), onCommitted: resolve });
+  });
+}
+
+function webglCanvas(view: TerminalView): HTMLCanvasElement {
+  for (const canvas of view.host.querySelectorAll(".xterm-screen canvas")) {
+    if (canvas instanceof HTMLCanvasElement && canvas.getContext("webgl2")) return canvas;
+  }
+  throw new Error("Real WebGL is required; DOM fallback cannot test glyph corruption");
+}
+
+async function mountPair() {
+  await page.viewport(1000, 600);
+  const active = mountTerminal(0);
+  const sibling = mountTerminal(460);
+  await document.fonts.ready;
+  await expect
+    .poll(() => active.host.querySelectorAll(".xterm-screen canvas").length)
+    .toBeGreaterThan(0);
+  await expect
+    .poll(() => sibling.host.querySelectorAll(".xterm-screen canvas").length)
+    .toBeGreaterThan(0);
+  webglCanvas(active);
+  webglCanvas(sibling);
+  await write(active, "\x1b[?25l");
+  await write(sibling, "\x1b[?25l");
+  return { active, sibling };
+}
+
+function captureHeader(input: { view: TerminalView; output?: string }): Promise<RowImage> {
+  const { view, output } = input;
+  return new Promise((resolve, reject) => {
+    const timeout = setTimeout(() => {
+      rendered.dispose();
+      reject(new Error("Terminal did not render within 2 seconds"));
+    }, 2000);
+    const rendered = view.terminal.onRender(() => {
+      rendered.dispose();
+      clearTimeout(timeout);
+      try {
+        // Copy during onRender, before WebGL discards its default drawing buffer.
+        const source = webglCanvas(view);
+        const canvas = document.createElement("canvas");
+        canvas.width = source.width;
+        canvas.height = Math.round(source.height / view.terminal.rows);
+        const context = canvas.getContext("2d");
+        if (!context) throw new Error("Canvas 2D pixel capture is unavailable");
+        context.drawImage(source, 0, 0);
+        const pixels = context.getImageData(0, 0, canvas.width, canvas.height).data;
+        resolve({ width: canvas.width, height: canvas.height, pixels });
+      } catch (error) {
+        reject(error);
+      }
+    });
+    if (output === undefined) view.terminal.refresh(0, view.terminal.rows - 1);
+    else view.runtime.write({ data: encodeTerminalOutput(output) });
+  });
+}
+
+function expectSamePixels(input: { expected: RowImage; actual: RowImage; label: string }): void {
+  const { expected, actual, label } = input;
+  expect(actual.width, label).toBe(expected.width);
+  expect(actual.height, label).toBe(expected.height);
+  let changed = 0;
+  for (let index = 0; index < expected.pixels.length; index += 1) {
+    if (expected.pixels[index] !== actual.pixels[index]) changed += 1;
+  }
+  expect(changed, label).toBe(0);
+}
+
+function coloredOutput(input: { cells: number; offset: number }): string {
+  const alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+  let output = "";
+  for (let index = 0; index < input.cells; index += 1) {
+    const value = index + input.offset;
+    const foreground = `${value % 256};${(value >> 8) % 256};${(value * 13) % 256}`;
+    const background = (value * 7) % 256;
+    output += `\x1b[38;2;${foreground}m\x1b[48;5;${background}m${alphabet[value % alphabet.length]}`;
+  }
+  return `${output}\x1b[0m`;
+}
+
+afterEach(() => {
+  for (const view of views.splice(0)) {
+    view.runtime.unmount();
+    view.root.remove();
+  }
+});
+
+it("preserves another terminal's glyph pixels when a shared atlas is cleared", async () => {
+  const { active, sibling } = await mountPair();
+  await write(sibling, header);
+  const before = await captureHeader({ view: sibling });
+  const visibleChannels = before.pixels.filter(
+    (channel, index) => index % 4 !== 3 && channel > 100,
+  );
+  expect(visibleChannels.length).toBeGreaterThan(100);
+
+  active.terminal.clearTextureAtlas();
+  await captureHeader({ view: active, output: coloredOutput({ cells: 2000, offset: 0 }) });
+  const after = await captureHeader({
+    view: sibling,
+    output: `\x1b[${sibling.terminal.rows};1Hx`,
+  });
+  expect(sibling.terminal.buffer.active.getLine(0)?.translateToString(true)).toBe(header);
+  expectSamePixels({ expected: before, actual: after, label: "sibling after atlas clear" });
+});
+
+it("preserves both headers while ordinary output grows the shared glyph atlas", async () => {
+  const { active, sibling } = await mountPair();
+  const cells = active.terminal.cols * (active.terminal.rows - 2);
+  // Startup glyphs can stay on an unmerged page and hide this bug. Allocate the
+  // reference after some output, as a real long-running TUI does.
+  for (let batch = 0; batch < 16; batch += 1) {
+    await captureHeader({
+      view: active,
+      output: `\x1b[H${coloredOutput({ cells, offset: batch * cells })}`,
+    });
+  }
+  const lateHeader = `\x1b[H\x1b[0m\x1b[2K\x1b[38;2;253;251;247m${header}\x1b[0m`;
+  await write(active, lateHeader);
+  await write(sibling, lateHeader);
+  const activeBefore = await captureHeader({ view: active });
+  const siblingBefore = await captureHeader({ view: sibling });
+
+  for (let batch = 0; batch < 256; batch += 1) {
+    const activeFrame = await captureHeader({
+      view: active,
+      output: `\x1b[2;1H${coloredOutput({ cells, offset: (batch + 16) * cells })}`,
+    });
+    const siblingFrame = await captureHeader({
+      view: sibling,
+      output: `\x1b[${sibling.terminal.rows};1H${batch % 10}`,
+    });
+    expect(active.terminal.buffer.active.getLine(0)?.translateToString(true)).toBe(header);
+    expect(sibling.terminal.buffer.active.getLine(0)?.translateToString(true)).toBe(header);
+    expectSamePixels({
+      expected: activeBefore,
+      actual: activeFrame,
+      label: `active frame ${batch}`,
+    });
+    expectSamePixels({
+      expected: siblingBefore,
+      actual: siblingFrame,
+      label: `sibling frame ${batch}`,
+    });
+  }
+}, 30000);

packages/app/src/timeline/session-stream-reducers.test.ts

@@ -19,6 +19,66 @@ import {
   type TimelineCursor,
 } from "./session-stream-reducers";
 
+it("keeps streamed reasoning together while the initial history is loading", () => {
+  let head: StreamItem[] = [];
+  const chunks = ["Checking a long oper", "ation before", " the re", "sult arrives."];
+  for (const [index, text] of chunks.entries()) {
+    const result = processAgentStreamEvent({
+      event: {
+        type: "timeline",
+        provider: "codex",
+        turnId: "turn-18",
+        item: { type: "reasoning", text },
+      },
+      seq: index + 1,
+      epoch: "epoch-1",
+      currentTail: [],
+      currentHead: head,
+      currentCursor: undefined,
+      timestamp: new Date(1000 + index),
+      hasAuthoritativeBaseline: false,
+    });
+    head = result.head;
+    expect(head).toHaveLength(1);
+    expect(head[0]).toMatchObject({
+      kind: "thought",
+      text: chunks.slice(0, index + 1).join(""),
+      turnId: "turn-18",
+    });
+  }
+});
+
+it.each([false, true])(
+  "keeps adjacent reasoning from different turns separate (history loaded: %s)",
+  (hasAuthoritativeBaseline) => {
+    let head: StreamItem[] = [];
+    let tail: StreamItem[] = [];
+    for (const [index, turnId] of ["turn-1", "turn-2"].entries()) {
+      const result = processAgentStreamEvent({
+        event: {
+          type: "timeline",
+          provider: "codex",
+          turnId,
+          item: { type: "reasoning", text: turnId },
+        },
+        seq: index + 1,
+        epoch: "epoch-1",
+        currentTail: tail,
+        currentHead: head,
+        currentCursor: undefined,
+        timestamp: new Date(1000),
+        hasAuthoritativeBaseline,
+      });
+      head = result.head;
+      tail = result.tail;
+    }
+    expect([...tail, ...head]).toMatchObject([
+      { kind: "thought", text: "turn-1", turnId: "turn-1" },
+      { kind: "thought", text: "turn-2", turnId: "turn-2" },
+    ]);
+  },
+);
+
 // ---------------------------------------------------------------------------
 // Test helpers
 // ---------------------------------------------------------------------------

packages/app/src/timeline/session-stream-reducers.ts

@@ -1615,19 +1615,17 @@ export function processAgentStreamEvent(
         unmatchedUserMessageInsert: "head",
       });
     } else {
-      const overlay = applyStreamEvent({
-        tail: currentHead,
-        head: [],
-        event,
-        timestamp,
+      // Before history arrives, the overlay is one ordered stream. Reducing it
+      // directly keeps consecutive reasoning chunks in the same row.
+      const overlay = reduceStreamUpdate(currentHead, event, timestamp, {
         source: "live",
         timelineCursor,
       });
       streamResult = {
         tail: currentTail,
-        head: [...overlay.tail, ...overlay.head],
+        head: overlay,
         changedTail: false,
-        changedHead: overlay.changedTail || overlay.changedHead,
+        changedHead: overlay !== currentHead,
       };
     }
   } else {

packages/app/src/timeline/timeline-replacement.test.ts

@@ -15,7 +15,7 @@ describe("requestTimelineReplacement", () => {
     await expect(requestTimelineReplacement(client, "agent-1")).rejects.toThrow("fetch complete");
 
     expect(requests).toEqual([
-      ["agent-1", { direction: "tail", projection: "projected", limit: 40 }],
+      ["agent-1", { direction: "tail", projection: "projected", wholeTurns: true, limit: 40 }],
     ]);
   });
 });

packages/app/src/timeline/timeline-sync-plan.test.ts

@@ -17,6 +17,7 @@ describe("timeline sync planning", () => {
       direction: "tail",
       limit: TIMELINE_FETCH_PAGE_SIZE,
       projection: "projected",
+      wholeTurns: true,
     });
   });
 
@@ -26,6 +27,7 @@ describe("timeline sync planning", () => {
       cursor: { epoch: "epoch-1", seq: 49 },
       limit: TIMELINE_FETCH_PAGE_SIZE,
       projection: "projected",
+      wholeTurns: true,
     });
   });
 
@@ -37,6 +39,7 @@ describe("timeline sync planning", () => {
       cursor: { epoch: "epoch-1", seq: 25 },
       limit: TIMELINE_FETCH_PAGE_SIZE,
       projection: "projected",
+      wholeTurns: true,
     });
   });
 
@@ -49,6 +52,7 @@ describe("timeline sync planning", () => {
       },
       limit: TIMELINE_FETCH_PAGE_SIZE,
       projection: "projected",
+      wholeTurns: true,
       mergeWindow: true,
     });
   });

packages/app/src/timeline/timeline-sync-plan.ts

@@ -9,6 +9,7 @@ export interface ProjectedTimelineTailFetchPlan {
   direction: "tail";
   limit: number;
   projection: "projected";
+  wholeTurns: true;
 }
 
 export interface ProjectedTimelineAfterFetchPlan {
@@ -16,6 +17,7 @@ export interface ProjectedTimelineAfterFetchPlan {
   cursor: TimelineSyncCursor;
   limit: number;
   projection: "projected";
+  wholeTurns: true;
 }
 
 export interface ProjectedTimelineBeforeFetchPlan {
@@ -23,6 +25,7 @@ export interface ProjectedTimelineBeforeFetchPlan {
   cursor: TimelineSyncCursor;
   limit: number;
   projection: "projected";
+  wholeTurns: true;
 }
 
 export type ProjectedTimelineFetchPlan =
@@ -40,6 +43,7 @@ export function planTimelineCatchUpAfter(cursor: TimelineSyncCursor) {
     cursor,
     limit: TIMELINE_FETCH_PAGE_SIZE,
     projection: "projected",
+    wholeTurns: true,
   } as const;
 }
 
@@ -48,6 +52,7 @@ export function planTimelineTailFetch() {
     direction: "tail",
     limit: TIMELINE_FETCH_PAGE_SIZE,
     projection: "projected",
+    wholeTurns: true,
   } as const;
 }
 
@@ -65,6 +70,7 @@ export function planTimelineOlderFetch(cursor: TimelineSyncCursor) {
     cursor,
     limit: TIMELINE_FETCH_PAGE_SIZE,
     projection: "projected",
+    wholeTurns: true,
   } as const;
 }
 
@@ -75,6 +81,7 @@ export function planTimelinePromptJump(target: TimelineSyncCursor) {
     cursor: { epoch: target.epoch, seq: target.seq + newerRows + 1 },
     limit: TIMELINE_FETCH_PAGE_SIZE,
     projection: "projected",
+    wholeTurns: true,
     mergeWindow: true,
   } as const;
 }

packages/app/src/timeline/turn-time.test.ts

@@ -51,7 +51,7 @@ describe("deriveStreamTurnTiming", () => {
     });
 
     assert.equal(timing.runningStartedAt, secondUserAt);
-    assert.equal(timing.byAssistantId.has("a2"), false);
+    assert.equal(timing.byItemId.has("a2"), false);
   });
 
   it("derives completed turn timing from user and assistant item timestamps", () => {
@@ -69,7 +69,7 @@ describe("deriveStreamTurnTiming", () => {
       head: [],
     });
 
-    assert.deepEqual(timing.byAssistantId.get("a1"), {
+    assert.deepEqual(timing.byItemId.get("a1"), {
       completedAt: assistantAt,
       durationMs: 7000,
     });
@@ -95,8 +95,8 @@ describe("deriveStreamTurnTiming", () => {
       completedAt: lastAssistantAt,
       durationMs: 7000,
     };
-    assert.deepEqual(timing.byAssistantId.get("a1"), expected);
-    assert.deepEqual(timing.byAssistantId.get("a2"), expected);
+    assert.deepEqual(timing.byItemId.get("a1"), expected);
+    assert.deepEqual(timing.byItemId.get("a2"), expected);
   });
 
   it("preserves the completion timestamp when a canonical turn has no visible prompt", () => {
@@ -120,7 +120,7 @@ describe("deriveStreamTurnTiming", () => {
       head: [],
     });
 
-    assert.deepEqual(timing.byAssistantId.get("hidden-prompt-a2"), {
+    assert.deepEqual(timing.byItemId.get("hidden-prompt-a2"), {
       completedAt: hiddenPromptTurnAt,
       durationMs: null,
     });
@@ -143,12 +143,12 @@ describe("deriveStreamTurnTiming", () => {
     const first = derive("one", "2026-05-15T00:01:04.000Z");
     const second = derive("one two", "2026-05-15T00:01:05.000Z");
 
-    assert.equal(second.byAssistantId, first.byAssistantId);
-    assert.deepEqual(first.byAssistantId.get("a1"), {
+    assert.equal(second.byItemId, first.byItemId);
+    assert.deepEqual(first.byItemId.get("a1"), {
       completedAt: tail[1]?.timestamp,
       durationMs: 7000,
     });
-    assert.equal(first.byAssistantId.has("a2"), false);
+    assert.equal(first.byItemId.has("a2"), false);
   });
 
   it("keeps the timing map identity when the head closed the tail's open turn", () => {
@@ -168,8 +168,8 @@ describe("deriveStreamTurnTiming", () => {
     const first = derive("one", "2026-05-15T00:01:04.000Z");
     const second = derive("one two", "2026-05-15T00:01:05.000Z");
 
-    assert.equal(second.byAssistantId, first.byAssistantId);
-    assert.deepEqual(first.byAssistantId.get("a1"), {
+    assert.equal(second.byItemId, first.byItemId);
+    assert.deepEqual(first.byItemId.get("a1"), {
       completedAt: lastTailAt,
       durationMs: 7000,
     });
@@ -193,9 +193,9 @@ describe("deriveStreamTurnTiming", () => {
       head,
     });
 
-    assert.notEqual(completed.byAssistantId, active.byAssistantId);
-    assert.equal(active.byAssistantId.has("a1"), false);
-    assert.deepEqual(completed.byAssistantId.get("a1"), { completedAt, durationMs: 9000 });
+    assert.notEqual(completed.byItemId, active.byItemId);
+    assert.equal(active.byItemId.has("a1"), false);
+    assert.deepEqual(completed.byItemId.get("a1"), { completedAt, durationMs: 9000 });
   });
 
   it("derives fresh timing when the tail itself changes", () => {
@@ -211,11 +211,39 @@ describe("deriveStreamTurnTiming", () => {
     const first = derive(firstTail);
     const second = derive(secondTail);
 
-    assert.notEqual(second.byAssistantId, first.byAssistantId);
-    assert.equal(first.byAssistantId.has("a2"), false);
-    assert.deepEqual(second.byAssistantId.get("a2"), {
+    assert.notEqual(second.byItemId, first.byItemId);
+    assert.equal(first.byItemId.has("a2"), false);
+    assert.deepEqual(second.byItemId.get("a2"), {
       completedAt: secondTail[3]?.timestamp,
       durationMs: 3000,
     });
   });
 });
+
+it("times a heartbeat that ends with tools and no assistant text", () => {
+  const trigger: StreamItem = {
+    kind: "tool_call",
+    id: "trigger",
+    timestamp: new Date("2026-05-15T00:00:00Z"),
+    turnId: "heartbeat",
+    payload: {
+      source: "agent",
+      data: {
+        provider: "claude",
+        callId: "trigger",
+        name: "heartbeat",
+        status: "completed",
+        error: null,
+        detail: { type: "plain_text", text: "Check progress" },
+      },
+    },
+  };
+  const tool: StreamItem = { ...trigger, id: "last", timestamp: new Date("2026-05-15T00:00:05Z") };
+  const timing = deriveStreamTurnTiming({
+    tail: [trigger, tool],
+    head: [],
+    isTurnActive: false,
+    activeTurnStartedAt: null,
+  });
+  assert.equal(timing.byItemId.get("last")?.durationMs, 5000);
+});

packages/app/src/timeline/turn-time.ts

@@ -1,5 +1,5 @@
 import type { StreamItem } from "@/types/stream";
-import { startsNewTurn } from "@/agent-stream/turn-membership";
+import { startsNewTurn, isTurnTrigger } from "@/agent-stream/turn-membership";
 
 export interface TurnTiming {
   completedAt: Date;
@@ -7,7 +7,7 @@ export interface TurnTiming {
 }
 
 export interface StreamTurnTiming {
-  byAssistantId: Map<string, TurnTiming>;
+  byItemId: Map<string, TurnTiming>;
   runningStartedAt: Date | null;
 }
 
@@ -20,7 +20,7 @@ interface OpenTurn {
 
 interface HeadTurnTiming {
   additions: Map<string, TurnTiming>;
-  byAssistantId: Map<string, TurnTiming>;
+  byItemId: Map<string, TurnTiming>;
 }
 
 interface TailTurnTiming {
@@ -37,14 +37,18 @@ const EMPTY_OPEN_TURN: OpenTurn = {
 };
 
 function closeTurn(turn: OpenTurn, into: Map<string, TurnTiming>): void {
-  if (!turn.lastItemAt || turn.assistantIds.length === 0) {
+  if (!turn.lastItemAt) {
     return;
   }
   const timing: TurnTiming = {
     completedAt: turn.lastItemAt,
     durationMs: turn.userAt ? Math.max(0, turn.lastItemAt.getTime() - turn.userAt.getTime()) : null,
   };
-  for (const id of turn.assistantIds) {
+  let footerIds = turn.assistantIds;
+  if (footerIds.length === 0 && turn.previousItem?.kind === "tool_call") {
+    footerIds = [turn.previousItem.id];
+  }
+  for (const id of footerIds) {
     into.set(id, timing);
   }
 }
@@ -61,7 +65,7 @@ function walkTurns(
   for (const item of items) {
     if (startsNewTurn(item, previousItem)) {
       closeTurn({ userAt, lastItemAt, assistantIds, previousItem }, into);
-      userAt = item.kind === "user_message" ? item.timestamp : null;
+      userAt = isTurnTrigger(item) ? item.timestamp : null;
       lastItemAt = null;
       assistantIds = [];
     }
@@ -108,7 +112,7 @@ function getTailTurnTiming(tail: StreamItem[]): TailTurnTiming {
   return timing;
 }
 
-function resolveByAssistantId(
+function resolveByItemId(
   tail: TailTurnTiming,
   additions: Map<string, TurnTiming>,
 ): Map<string, TurnTiming> {
@@ -116,14 +120,14 @@ function resolveByAssistantId(
     return tail.completed;
   }
   if (tail.lastHead && areTimingsEqual(tail.lastHead.additions, additions)) {
-    return tail.lastHead.byAssistantId;
+    return tail.lastHead.byItemId;
   }
-  const byAssistantId = new Map(tail.completed);
+  const byItemId = new Map(tail.completed);
   for (const [id, timing] of additions) {
-    byAssistantId.set(id, timing);
+    byItemId.set(id, timing);
   }
-  tail.lastHead = { additions, byAssistantId };
-  return byAssistantId;
+  tail.lastHead = { additions, byItemId };
+  return byItemId;
 }
 
 export function deriveStreamTurnTiming(params: {
@@ -139,7 +143,7 @@ export function deriveStreamTurnTiming(params: {
     closeTurn(openTurn, additions);
   }
   return {
-    byAssistantId: resolveByAssistantId(tail, additions),
+    byItemId: resolveByItemId(tail, additions),
     runningStartedAt: params.isTurnActive ? params.activeTurnStartedAt : null,
   };
 }

packages/app/src/timeline/viewed-timeline-sync.test.ts

@@ -189,6 +189,7 @@ class TimelineWorld {
           direction: "tail",
           limit: 40,
           projection: "projected",
+          wholeTurns: true,
         });
       } finally {
         this.forcedTimelineTailReplacements.delete(agentId);
@@ -341,7 +342,12 @@ test("uses a tail fetch when an agent becomes visible", async () => {
   membership.succeed();
 
   const fetch = await world.nextFetch("agent-a");
-  expect(fetch.request).toEqual({ direction: "tail", limit: 40, projection: "projected" });
+  expect(fetch.request).toEqual({
+    direction: "tail",
+    limit: 40,
+    projection: "projected",
+    wholeTurns: true,
+  });
   fetch.respond({ hasNewer: false });
 });
 
@@ -366,6 +372,7 @@ test("loads the cache before choosing the authoritative network request", async
     cursor: { epoch: "cached-epoch", seq: 17 },
     limit: 40,
     projection: "projected",
+    wholeTurns: true,
   });
   fetch.respond({ hasNewer: false });
 });
@@ -384,6 +391,7 @@ test("catches up after the restored cursor when an agent becomes visible", async
     cursor: { epoch: "epoch-agent-a", seq: 42 },
     limit: 40,
     projection: "projected",
+    wholeTurns: true,
   });
   fetch.respond({ hasNewer: false });
 });
@@ -401,7 +409,12 @@ test("falls back to the latest tail when a restored cursor has more than one cat
   probe.respond({ hasNewer: true, seq: 82 });
 
   const fallback = await world.nextFetch("agent-a");
-  expect(fallback.request).toEqual({ direction: "tail", limit: 40, projection: "projected" });
+  expect(fallback.request).toEqual({
+    direction: "tail",
+    limit: 40,
+    projection: "projected",
+    wholeTurns: true,
+  });
   expect(
     world.applyTimelineResponse({
       requestId: "fallback-tail",
@@ -444,6 +457,7 @@ test("a gap absorbed by a running tail is recovered after the tail completes", a
     cursor: { epoch: "epoch-agent-a", seq: 9 },
     limit: 40,
     projection: "projected",
+    wholeTurns: true,
   });
   recovery.respond({ hasNewer: false });
   await vi.waitFor(() => expect(world.sync.getAgentTimelineStatus("agent-a")).toBe("ready"));
@@ -527,6 +541,7 @@ test("unchanged visible-set publication does not cancel paged catch-up", async (
     cursor: { epoch: "epoch-agent-a", seq: 5 },
     limit: 40,
     projection: "projected",
+    wholeTurns: true,
   });
   world.expectNoPendingMembership();
 });
@@ -897,12 +912,14 @@ test("gap recovery supersedes completed catch-up and pages through the current t
       cursor: { epoch: "epoch-agent-a", seq: 10 },
       limit: 40,
       projection: "projected",
+      wholeTurns: true,
     },
     {
       direction: "after",
       cursor: { epoch: "epoch-agent-a", seq: 15 },
       limit: 40,
       projection: "projected",
+      wholeTurns: true,
     },
   ]);
 });

packages/app/src/tool-calls/detail-level/grouping.ts

@@ -1,5 +1,6 @@
+import { isTurnTrigger, isTurnBoundary } from "@/agent-stream/turn-membership";
 import type { ToolCallDetail } from "@getpaseo/protocol/agent-types";
-import type { StreamItem, ToolCallItem } from "@/types/stream";
+import type { StreamItem, ToolCallItem, ThoughtItem } from "@/types/stream";
 
 export interface ToolCallDescriptor {
   detail: ToolCallDetail;
@@ -9,17 +10,19 @@ export interface ToolCallDescriptor {
   metadata?: Record<string, unknown>;
 }
 
+export type GroupableItem = ToolCallItem | ThoughtItem;
+
 export interface ToolCallRun {
   id: string;
-  calls: readonly ToolCallItem[];
-  latest: ToolCallItem;
+  calls: readonly GroupableItem[];
+  latest: GroupableItem;
   isSealed: boolean;
 }
 
 export interface GroupedHistory<TGroup> {
   tail: StreamItem[];
   groupsByHostId: Map<string, TGroup>;
-  pendingCalls: readonly ToolCallItem[];
+  pendingCalls: readonly GroupableItem[];
 }
 
 export interface GroupedToolCalls<TGroup> {
@@ -62,15 +65,19 @@ export function describeToolCall(item: ToolCallItem): ToolCallDescriptor {
   };
 }
 
-export function isGroupableToolCall(item: StreamItem): item is ToolCallItem {
-  if (item.kind !== "tool_call") {
+export function isGroupableToolCall(
+  item: StreamItem,
+  autoExpandReasoning = false,
+): item is GroupableItem {
+  if (item.kind === "thought") return !autoExpandReasoning;
+  if (item.kind !== "tool_call" || isTurnTrigger(item)) {
     return false;
   }
   const descriptor = describeToolCall(item);
   return descriptor.detail.type !== "plan" && descriptor.name.trim().toLowerCase() !== "speak";
 }
 
-function createRun(calls: readonly ToolCallItem[], isSealed: boolean): ToolCallRun {
+function createRun(calls: readonly GroupableItem[], isSealed: boolean): ToolCallRun {
   const first = calls[0];
   const latest = calls.at(-1);
   if (!first || !latest) {
@@ -79,20 +86,21 @@ function createRun(calls: readonly ToolCallItem[], isSealed: boolean): ToolCallR
   return { id: first.id, calls, latest, isSealed };
 }
 
-function createHost(run: ToolCallRun): ToolCallItem {
+function createHost(run: ToolCallRun): GroupableItem {
   if (run.calls.length === 1) {
     return run.latest;
   }
   return { ...run.latest, id: run.id };
 }
 
-function isRunning(call: ToolCallItem): boolean {
+function isRunning(call: GroupableItem): boolean {
+  if (call.kind === "thought") return call.status !== "ready";
   const status = describeToolCall(call).status;
   return status === "running" || status === "executing";
 }
 
 function appendRun<TGroup>(input: {
-  calls: readonly ToolCallItem[];
+  calls: readonly GroupableItem[];
   isSealed: boolean;
   output: StreamItem[];
   groups: Map<string, TGroup>;
@@ -110,13 +118,17 @@ function appendRun<TGroup>(input: {
 export function prepareGroupedHistory<TGroup>(input: {
   tail: StreamItem[];
   buildGroup: (run: ToolCallRun) => TGroup;
+  autoExpandReasoning?: boolean;
 }): GroupedHistory<TGroup> {
   const output: StreamItem[] = [];
   const groups = new Map<string, TGroup>();
-  let pending: ToolCallItem[] = [];
+  let pending: GroupableItem[] = [];
 
   for (const item of input.tail) {
-    if (isGroupableToolCall(item)) {
+    if (
+      isGroupableToolCall(item, input.autoExpandReasoning) &&
+      !isTurnBoundary(pending.at(-1) ?? null, item)
+    ) {
       pending.push(item);
       continue;
     }
@@ -128,7 +140,8 @@ export function prepareGroupedHistory<TGroup>(input: {
       buildGroup: input.buildGroup,
     });
     pending = [];
-    output.push(item);
+    if (isGroupableToolCall(item, input.autoExpandReasoning)) pending.push(item);
+    else output.push(item);
   }
 
   appendRun({
@@ -151,6 +164,7 @@ export function groupLiveToolCalls<TGroup>(input: {
   head: StreamItem[];
   isTurnActive: boolean;
   buildGroup: (run: ToolCallRun) => TGroup;
+  autoExpandReasoning?: boolean;
 }): GroupedToolCalls<TGroup> {
   const head: StreamItem[] = [];
   const liveGroups = new Map<string, TGroup>();
@@ -175,7 +189,8 @@ export function groupLiveToolCalls<TGroup>(input: {
   };
 
   for (const item of input.head) {
-    if (isGroupableToolCall(item)) {
+    if (isTurnBoundary(pending.at(-1) ?? null, item)) flush(true);
+    if (isGroupableToolCall(item, input.autoExpandReasoning)) {
       if (pending.length === 0) {
         hostPlacement = "head";
       }

packages/app/src/tool-calls/detail-level/overview/label.ts

@@ -33,13 +33,18 @@ export function useOverviewSummaryLabel(
       [summary.readFileCount, "toolCallGroup.readFiles"],
       [summary.searchCount, "toolCallGroup.searches"],
       [summary.otherToolCount, "toolCallGroup.otherTools"],
-      [summary.paseoCallCount, "toolCallGroup.paseoCalls"],
     ] as const;
     for (const [count, key] of entries) {
       if (count > 0) {
         parts.push(t(`${key}.${count === 1 ? "one" : "other"}`, { count }));
       }
     }
+    for (const [action, count] of Object.entries(summary.paseoActions)) {
+      parts.push(
+        count === 1 ? action.toLocaleLowerCase() : `${action.toLocaleLowerCase()} ×${count}`,
+      );
+    }
+    if (summary.thoughtCount > 0) parts.push(t("toolCallGroup.thought").toLocaleLowerCase());
     return joinSummaryParts(parts, t("toolCallGroup.and"));
   }, [leadingParts, summary, t]);
 }

packages/app/src/tool-calls/detail-level/overview/model.ts

@@ -1,17 +1,18 @@
-import { isPaseoToolName } from "@getpaseo/protocol/tool-name-normalization";
-import type { ToolCallItem } from "@/types/stream";
-import { describeToolCall, type ToolCallRun } from "../grouping";
+import { getPaseoToolActionLabel } from "@getpaseo/protocol/paseo-tool-presentation/index";
+import { isTurnTrigger } from "@/agent-stream/turn-membership";
+
+import { describeToolCall, type GroupableItem, type ToolCallRun } from "../grouping";
 
-const DIRECT_PASEO_TOOL_PREFIX = "paseo_";
 const DIRECT_SEARCH_TOOL_SUFFIX_PATTERN = /(?:^|[_.:/])(?:web_search|llm_context)$/;
 
 export interface OverviewSummary {
+  thoughtCount: number;
   editedFileCount: number;
   commandCount: number;
   readFileCount: number;
   searchCount: number;
   otherToolCount: number;
-  paseoCallCount: number;
+  paseoActions: Record<string, number>;
 }
 
 export interface OverviewToolCallGroup {
@@ -21,28 +22,31 @@ export interface OverviewToolCallGroup {
   isLoading: boolean;
 }
 
-function isPaseoCall(name: string, normalizedName: string): boolean {
-  return isPaseoToolName(name) || normalizedName.startsWith(DIRECT_PASEO_TOOL_PREFIX);
-}
-
 function isSearchCall(name: string): boolean {
   return DIRECT_SEARCH_TOOL_SUFFIX_PATTERN.test(name);
 }
 
 /** Counts tool calls by what they did, for any summary of a stretch of agent work. */
-export function summarizeToolCalls(calls: readonly ToolCallItem[]): OverviewSummary {
+export function summarizeToolCalls(calls: readonly GroupableItem[]): OverviewSummary {
   const editedFiles = new Set<string>();
   const readFiles = new Set<string>();
+  let thoughtCount = 0;
   let commandCount = 0;
   let searchCount = 0;
   let otherToolCount = 0;
-  let paseoCallCount = 0;
+  const paseoActions: Record<string, number> = {};
 
   for (const call of calls) {
+    if (call.kind === "thought") {
+      thoughtCount += 1;
+      continue;
+    }
+    if (isTurnTrigger(call)) continue;
     const descriptor = describeToolCall(call);
     const normalizedName = descriptor.name.trim().toLowerCase();
-    if (isPaseoCall(descriptor.name, normalizedName)) {
-      paseoCallCount += 1;
+    const action = getPaseoToolActionLabel(descriptor.name);
+    if (action) {
+      paseoActions[action] = (paseoActions[action] ?? 0) + 1;
     } else if (descriptor.detail.type === "edit" || descriptor.detail.type === "write") {
       editedFiles.add(descriptor.detail.filePath);
     } else if (descriptor.detail.type === "shell") {
@@ -57,17 +61,19 @@ export function summarizeToolCalls(calls: readonly ToolCallItem[]): OverviewSumm
   }
 
   return {
+    thoughtCount,
     editedFileCount: editedFiles.size,
     commandCount,
     readFileCount: readFiles.size,
     searchCount,
     otherToolCount,
-    paseoCallCount,
+    paseoActions,
   };
 }
 
 export function buildOverviewGroup(run: ToolCallRun): OverviewToolCallGroup {
   const isLoading = run.calls.some((call) => {
+    if (call.kind === "thought") return call.status !== "ready";
     const status = describeToolCall(call).status;
     return status === "running" || status === "executing";
   });

packages/app/src/tool-calls/detail-level/projection.test.ts

@@ -255,12 +255,13 @@ describe("tool call detail-level projection", () => {
       run: expect.any(Object),
       isLoading: false,
       summary: {
+        thoughtCount: 0,
         editedFileCount: 1,
         commandCount: 1,
         readFileCount: 2,
         searchCount: 0,
         otherToolCount: 0,
-        paseoCallCount: 0,
+        paseoActions: {},
       },
     });
   });
@@ -328,7 +329,7 @@ describe("tool call detail-level projection", () => {
     const result = project({ level: "overview", head: calls });
 
     expect(result.groupsByHostId.get("1")).toMatchObject({
-      summary: { otherToolCount: 2, paseoCallCount: 2 },
+      summary: { otherToolCount: 2, paseoActions: { "Listed agents": 1, "List worktrees": 1 } },
     });
   });
 
@@ -346,7 +347,11 @@ describe("tool call detail-level projection", () => {
     const result = project({ level: "overview", head: calls });
 
     expect(result.groupsByHostId.get("1")).toMatchObject({
-      summary: { searchCount: 3, otherToolCount: 0, paseoCallCount: 3 },
+      summary: {
+        searchCount: 3,
+        otherToolCount: 0,
+        paseoActions: { "Listed providers": 1, "List worktrees": 2 },
+      },
     });
   });
 
@@ -480,3 +485,56 @@ describe("tool call detail-level projection", () => {
     expect(result.groupsByHostId.size).toBe(1);
   });
 });
+
+it("keeps a heartbeat trigger visible outside grouped work", () => {
+  const trigger = toolCall(
+    "1",
+    { type: "plain_text", text: "Check progress" },
+    { name: "heartbeat" },
+  );
+  const work = toolCall("2", { type: "shell", command: "pwd" });
+  const result = project({ level: "overview", tail: [trigger, work] });
+  expect(result.tail.map((item) => item.id)).toEqual(["1", "2"]);
+  expect(result.groupsByHostId.has("1")).toBe(false);
+});
+
+it("does not merge tools from different canonical turns", () => {
+  const first = toolCall("1", { type: "shell", command: "pwd" });
+  first.turnId = "first";
+  const second = toolCall("2", { type: "shell", command: "ls" });
+  second.turnId = "second";
+  const result = project({ level: "overview", tail: [first, second] });
+  expect(result.tail.map((item) => item.id)).toEqual(["1", "2"]);
+});
+
+it.each([false, true])(
+  "handles streaming reasoning across retained history (Expand thinking %s)",
+  (autoExpandReasoning) => {
+    const call = { ...toolCall("1", { type: "shell", command: "echo ok" }), turnId: "run" };
+    const thought: StreamItem = {
+      kind: "thought",
+      id: "reasoning",
+      text: "Checking",
+      status: "loading",
+      timestamp: new Date(),
+      turnId: "run",
+    };
+    const tail = [call];
+    const result = project({
+      level: "overview",
+      tail,
+      head: [thought],
+      isTurnActive: true,
+      preparedHistory: prepareToolCallHistory("overview", tail, autoExpandReasoning),
+    });
+    expect(result.head).toEqual(autoExpandReasoning ? [thought] : []);
+    expect(result.groupsByHostId.get(call.id)?.run.calls).toEqual(
+      autoExpandReasoning ? [call] : [call, thought],
+    );
+    expect(result.groupsByHostId.get(call.id)?.summary).toMatchObject({
+      commandCount: 1,
+      otherToolCount: 0,
+      thoughtCount: autoExpandReasoning ? 0 : 1,
+    });
+  },
+);

packages/app/src/tool-calls/detail-level/projection.ts

@@ -13,6 +13,7 @@ export type ToolCallDetailGroup = OverviewToolCallGroup;
 
 export interface PreparedToolCallHistory {
   mode: "overview";
+  autoExpandReasoning: boolean;
   grouped: GroupedHistory<ToolCallDetailGroup>;
 }
 
@@ -41,15 +42,18 @@ function visibleToolCallItems(items: StreamItem[]): StreamItem[] {
 export function prepareToolCallHistory(
   level: ToolCallDetailLevel,
   tail: StreamItem[],
+  autoExpandReasoning = false,
 ): PreparedToolCallHistory | null {
   if (level === "detailed") {
     return null;
   }
   return {
     mode: "overview",
+    autoExpandReasoning,
     grouped: prepareGroupedHistory({
       tail: visibleToolCallItems(tail),
       buildGroup: buildOverviewGroup,
+      autoExpandReasoning,
     }),
   };
 }
@@ -74,6 +78,7 @@ export function projectToolCallDetailLevel(input: {
   }
   return groupLiveToolCalls({
     history: input.preparedHistory.grouped,
+    autoExpandReasoning: input.preparedHistory.autoExpandReasoning,
     head: visibleToolCallItems(input.head),
     isTurnActive: input.isTurnActive,
     buildGroup: buildOverviewGroup,

packages/app/src/types/stream.test.ts

@@ -661,6 +661,82 @@ describe("stream reducer canonical tool calls", () => {
     expect(new Set(tools.map((tool) => tool.id)).size).toBe(2);
   });
 
+  it.each(["live", "canonical"] as const)(
+    "keeps current tool identity during %s updates when an older turn reports late",
+    (source) => {
+      let state: StreamItem[] = [];
+      const events = [
+        { callId: "background", turnId: "codex-turn-17", status: "running" as const },
+        { callId: "exec-current", turnId: "codex-turn-18", status: "running" as const },
+        { callId: "background", turnId: "codex-turn-17", status: "completed" as const },
+        { callId: "exec-current", turnId: "codex-turn-18", status: "completed" as const },
+      ];
+      for (const [index, item] of events.entries()) {
+        state = reduceStreamUpdate(
+          state,
+          canonicalToolTimeline({
+            provider: "codex",
+            name: "exec_command",
+            ...item,
+          }),
+          new Date(index * 1000),
+          { source },
+        );
+      }
+      expect(
+        state.filter(isAgentToolCallItem).map((item) => ({
+          id: item.id,
+          turnId: item.turnId,
+          status: item.payload.data.status,
+        })),
+      ).toEqual([
+        {
+          id: "agent_tool_turn:codex-turn-17/background",
+          turnId: "codex-turn-17",
+          status: "completed",
+        },
+        {
+          id: "agent_tool_turn:codex-turn-18/exec-current",
+          turnId: "codex-turn-18",
+          status: "completed",
+        },
+      ]);
+    },
+  );
+
+  it("does not move reasoning into an older turn when a late tool update finalizes it", () => {
+    const background = canonicalToolTimeline({
+      provider: "codex",
+      name: "exec_command",
+      callId: "background",
+      turnId: "old",
+      status: "running",
+    });
+    let state = reduceStreamUpdate([], background, new Date(0));
+    state = reduceStreamUpdate(
+      state,
+      {
+        type: "timeline",
+        provider: "codex",
+        turnId: "current",
+        item: { type: "reasoning", text: "Working on the current request" },
+      },
+      new Date(1),
+    );
+    state = reduceStreamUpdate(
+      state,
+      canonicalToolTimeline({
+        provider: "codex",
+        name: "exec_command",
+        callId: "background",
+        turnId: "old",
+        status: "completed",
+      }),
+      new Date(2),
+    );
+    expect(state.at(-1)).toMatchObject({ kind: "thought", turnId: "current", status: "ready" });
+  });
+
   it("merges lifecycle updates for the same call occurrence", () => {
     const callId = "tool-updated-within-turn";
     const turnId = "autonomous-turn-1";

packages/app/src/types/stream.ts

@@ -91,6 +91,8 @@ export type StreamItem =
 export type UserMessageImageAttachment = AttachmentMetadata;
 
 export interface UserMessageItem {
+  /** Attribution added by presentation for received agent messages. */
+  sender?: AgentMessage["sender"];
   kind: "user_message";
   id: string;
   clientMessageId?: string;
@@ -986,6 +988,7 @@ function appendThought(
   text: string,
   timestamp: Date,
   timelineCursor?: TimelinePosition,
+  turnId?: string,
 ): StreamItem[] {
   const { chunk, hasContent } = normalizeChunk(text);
   if (!chunk) {
@@ -993,7 +996,7 @@ function appendThought(
   }
 
   const last = state[state.length - 1];
-  if (last && last.kind === "thought") {
+  if (last && last.kind === "thought" && last.turnId === turnId) {
     const updated: ThoughtItem = {
       ...last,
       ...(timelineCursor ? { timelineCursor } : {}),
@@ -1511,36 +1514,30 @@ function reduceTimelineEvent(
   const item = event.item;
   switch (item.type) {
     case "user_message":
-      return finalizeActiveThoughts(
-        appendUserMessage(
-          state,
-          item.text,
-          timestamp,
-          source,
-          item.messageId,
-          item.clientMessageId,
-          timelineCursor,
-          event.turnId,
-        ),
+      return appendUserMessage(
+        state,
+        item.text,
+        timestamp,
+        source,
+        item.messageId,
+        item.clientMessageId,
+        timelineCursor,
+        event.turnId,
       );
     case "assistant_message":
-      return finalizeActiveThoughts(
-        appendAssistantMessage(
-          state,
-          item.text,
-          timestamp,
-          source,
-          item.messageId,
-          reservedItemIds,
-          timelineCursor,
-        ),
+      return appendAssistantMessage(
+        state,
+        item.text,
+        timestamp,
+        source,
+        item.messageId,
+        reservedItemIds,
+        timelineCursor,
       );
     case "reasoning":
-      return appendThought(state, item.text, timestamp, timelineCursor);
+      return appendThought(state, item.text, timestamp, timelineCursor, event.turnId);
     case "tool_call":
-      return finalizeActiveThoughts(
-        reduceTimelineToolCall(state, event, item, timestamp, timelineCursor),
-      );
+      return reduceTimelineToolCall(state, event, item, timestamp, timelineCursor);
     case "todo": {
       const items: TodoEntry[] = (item.items ?? []).map((todo) => ({
         text: todo.text,
@@ -1549,9 +1546,7 @@ function reduceTimelineEvent(
         status: todo.status,
         activeForm: todo.activeForm,
       }));
-      return finalizeActiveThoughts(
-        appendTodoList(state, event.provider, items, timestamp, timelineCursor),
-      );
+      return appendTodoList(state, event.provider, items, timestamp, timelineCursor);
     }
     case "error": {
       const notification: NotificationItem = {
@@ -1563,7 +1558,7 @@ function reduceTimelineEvent(
         level: "error",
         message: item.message ?? "Unknown error",
       };
-      return finalizeActiveThoughts(appendNotification(state, notification));
+      return appendNotification(state, notification);
     }
     case "notification": {
       const notification: NotificationItem = {
@@ -1575,16 +1570,12 @@ function reduceTimelineEvent(
         level: item.level,
         message: item.message,
       };
-      return finalizeActiveThoughts(appendNotification(state, notification));
+      return appendNotification(state, notification);
     }
     case "compaction":
-      return finalizeActiveThoughts(
-        reduceTimelineCompaction(state, item, timestamp, timelineCursor),
-      );
+      return reduceTimelineCompaction(state, item, timestamp, timelineCursor);
     case "plugin":
-      return finalizeActiveThoughts(
-        appendPluginTimelineItem(state, item, timestamp, timelineCursor),
-      );
+      return appendPluginTimelineItem(state, item, timestamp, timelineCursor);
     default:
       return state;
   }
@@ -1601,8 +1592,9 @@ export function reduceStreamUpdate(
 ): StreamItem[] {
   const source = options?.source ?? "live";
   switch (event.type) {
-    case "timeline":
-      return applyTimelineTurnId(
+    case "timeline": {
+      const updated = applyTimelineTurnId(
+        state,
         reduceTimelineEvent(
           state,
           event,
@@ -1613,6 +1605,8 @@ export function reduceStreamUpdate(
         ),
         event,
       );
+      return event.item.type === "reasoning" ? updated : finalizeActiveThoughts(updated);
+    }
     case "thread_started":
     case "turn_started":
     case "turn_completed":
@@ -1628,6 +1622,7 @@ export function reduceStreamUpdate(
 }
 
 function applyTimelineTurnId(
+  previous: StreamItem[],
   items: StreamItem[],
   event: Extract<AgentStreamEventPayload, { type: "timeline" }>,
 ): StreamItem[] {
@@ -1637,15 +1632,14 @@ function applyTimelineTurnId(
     return reconcileCanonicalUserTurnMembership(items, clientMessageId, event.turnId);
   }
 
-  if (!event.turnId || items.length === 0) return items;
-  const index = items.length - 1;
-  const last = items[index];
-  if (!last || last.turnId === event.turnId) return items;
-  return [
-    ...items.slice(0, index),
-    { ...last, turnId: event.turnId } as StreamItem,
-    ...items.slice(index + 1),
-  ];
+  if (!event.turnId || items === previous) return items;
+  // Assign membership only to rows written by this event, before finalizing
+  // unrelated reasoning rows. Late lifecycle updates can replace an earlier row.
+  return items.map((item, index) =>
+    item === previous[index] || item.turnId === event.turnId
+      ? item
+      : ({ ...item, turnId: event.turnId } as StreamItem),
+  );
 }
 
 function reconcileCanonicalUserTurnMembership(

packages/app/vitest.config.ts

@@ -96,7 +96,10 @@ export default defineConfig({
           include: ["src/**/*.browser.{test,spec}.{ts,tsx}"],
           browser: {
             enabled: true,
-            provider: playwright(),
+            provider: playwright({
+              // Exercise real WebGL glyph rendering on GPU-less CI runners.
+              launchOptions: { args: ["--enable-unsafe-swiftshader"] },
+            }),
             headless: true,
             connectTimeout: 180_000,
             instances: [{ browser: "chromium" }],

packages/client/src/daemon-client.test.ts

@@ -1640,6 +1640,77 @@ test("preserves legacy fetchAgent id overload", async () => {
   await expect(responsePromise).rejects.toThrow("legacy fetch sentinel");
 });
 
+test.each([undefined, false, true])(
+  "loads history with whole-turn support advertised as %s",
+  async (wholeTurnTimeline) => {
+    const transport = createMockTransport();
+    const client = new DaemonClient({
+      url: "ws://test",
+      clientId: "history-compatibility",
+      reconnect: { enabled: false },
+      transportFactory: () => transport.transport,
+    });
+    clients.push(client);
+    const connected = client.connect();
+    transport.triggerOpen({
+      features: wholeTurnTimeline === undefined ? {} : { wholeTurnTimeline },
+    });
+    await connected;
+
+    const requests = [
+      { direction: "tail" as const },
+      { direction: "before" as const, cursor: { epoch: "epoch-1", seq: 50 } },
+      { direction: "after" as const, cursor: { epoch: "epoch-1", seq: 50 } },
+      { direction: "before" as const, cursor: { epoch: "epoch-1", seq: 80 }, mergeWindow: true },
+    ];
+    for (const [index, request] of requests.entries()) {
+      const requestId = `history-${index}`;
+      const result = client.fetchAgentTimeline("agent-1", {
+        ...request,
+        requestId,
+        wholeTurns: true,
+        limit: 40,
+        projection: "projected",
+      });
+      // Attach immediately so the old rejection is captured by the regression.
+      const completed = expect(result).resolves.toMatchObject({ requestId, entries: [] });
+      expect(parseSentFrame(transport.sent.at(-1))).toEqual({
+        type: "fetch_agent_timeline_request",
+        agentId: "agent-1",
+        requestId,
+        ...request,
+        limit: 40,
+        projection: "projected",
+        ...(wholeTurnTimeline === true ? { wholeTurns: true } : {}),
+      });
+      transport.triggerMessage(
+        wrapSessionMessage({
+          type: "fetch_agent_timeline_response",
+          payload: {
+            requestId,
+            agentId: "agent-1",
+            agent: null,
+            direction: request.direction,
+            projection: "projected",
+            epoch: "epoch-1",
+            reset: false,
+            staleCursor: false,
+            gap: false,
+            window: { minSeq: 0, maxSeq: 0, nextSeq: 1 },
+            startCursor: null,
+            endCursor: null,
+            hasOlder: false,
+            hasNewer: false,
+            entries: [],
+            error: null,
+          },
+        }),
+      );
+      await completed;
+    }
+  },
+);
+
 test("honors explicit fetchAgentTimeline timeout below the session RPC default", async () => {
   useHeartbeatClock();
   const logger = createMockLogger();

packages/client/src/daemon-client.ts

@@ -686,6 +686,8 @@ export interface FetchAgentOptions {
 }
 type LegacyFetchAgentOptions = Omit<FetchAgentOptions, "agentId">;
 export interface FetchAgentTimelineOptions {
+  /** Prefer whole-turn pages when supported; older hosts retain item-based paging. */
+  wholeTurns?: boolean;
   direction?: FetchAgentTimelineDirection;
   cursor?: FetchAgentTimelineCursor;
   limit?: number;
@@ -3548,9 +3550,15 @@ export class DaemonClient {
     agentId: string,
     options: FetchAgentTimelineOptions = {},
   ): Promise<FetchAgentTimelinePayload> {
+    // COMPAT(wholeTurnTimeline): added after v0.13.2 (#8010); remove after 2027-04-27 once the daemon floor supports whole-turn pages.
+    // Reading history predates this capability and must keep working on older hosts.
+    const supportsWholeTurns = this.lastServerInfoMessage?.features?.wholeTurnTimeline === true;
     const resolvedRequestId = this.createRequestId(options.requestId);
     const message = SessionInboundMessageSchema.parse({
       type: "fetch_agent_timeline_request",
+      ...(supportsWholeTurns && options.wholeTurns !== undefined
+        ? { wholeTurns: options.wholeTurns }
+        : {}),
       agentId,
       requestId: resolvedRequestId,
       ...(options.direction ? { direction: options.direction } : {}),

packages/client/src/index.test.ts

@@ -1770,3 +1770,66 @@ test("qualified parents preserve foreign identity without resolving an equal loc
   await client.close();
   expect(localParent.address).toEqual({ serverId: "srv_sdk_test", agentId: "same-parent" });
 });
+
+test("agent reload reopens through the daemon RPC then returns the observed snapshot; refresh remains a read", async () => {
+  const { client, ws } = await connectClient();
+  try {
+    const agent = client.agents.ref("agent_sdk");
+    const snapshot = createAgent();
+    const reloaded = agent.reload({ requestId: "reload-sdk" });
+    expect(parseSentSessionMessage(ws.sent.at(-1))).toMatchObject({
+      type: "refresh_agent_request",
+      agentId: "agent_sdk",
+      requestId: "reload-sdk",
+    });
+    ws.message(
+      sessionMessage({
+        type: "status",
+        payload: {
+          status: "agent_refreshed",
+          requestId: "reload-sdk",
+          agentId: "agent_sdk",
+          timelineSize: 0,
+        },
+      }),
+    );
+    await expect
+      .poll(() => parseSentSessionMessage(ws.sent.at(-1)).type)
+      .toBe("fetch_agent_request");
+    const fetched = parseSentSessionMessage(ws.sent.at(-1));
+    ws.message(
+      sessionMessage({
+        type: "fetch_agent_response",
+        payload: {
+          requestId: fetched.requestId,
+          agentId: "agent_sdk",
+          agent: snapshot,
+          project: null,
+          error: null,
+        },
+      }),
+    );
+    expect(await reloaded).toEqual({ agent: snapshot, project: null });
+    expect(agent.current()).toEqual(snapshot);
+    const read = agent.refresh("snapshot-read");
+    expect(parseSentSessionMessage(ws.sent.at(-1))).toMatchObject({
+      type: "fetch_agent_request",
+      requestId: "snapshot-read",
+    });
+    ws.message(
+      sessionMessage({
+        type: "fetch_agent_response",
+        payload: {
+          requestId: "snapshot-read",
+          agentId: "agent_sdk",
+          agent: snapshot,
+          project: null,
+          error: null,
+        },
+      }),
+    );
+    expect(await read).toEqual({ agent: snapshot, project: null });
+  } finally {
+    await client.close();
+  }
+});

packages/client/src/index.ts

@@ -369,6 +369,11 @@ export interface PaseoAgentHandle {
   readonly timeline: PaseoAgentTimelineHandle;
   current(): PaseoAgent | null;
   refresh(requestId?: string): Promise<PaseoAgentRefetchResult | null>;
+  /**
+   * Reopens the provider session with current configuration, rerunning session-open hooks.
+   * Interrupts a running turn and returns the refreshed snapshot.
+   */
+  reload(options?: { requestId?: string }): Promise<PaseoAgentRefetchResult | null>;
   send(text: string, options?: PaseoAgentSendOptions): Promise<void>;
   respondToPermission(options: PaseoAgentRespondToPermissionOptions): Promise<void>;
   /** Sends a prompt and resolves when that turn finishes or needs attention. */
@@ -981,6 +986,12 @@ function createAgentHandleFactory(
         current = result?.agent ?? null;
         return result;
       },
+      reload: async (options) => {
+        await daemonClient.refreshAgent(id, options?.requestId);
+        const result = await daemonClient.fetchAgent({ agentId: id });
+        current = result?.agent ?? null;
+        return result;
+      },
       send: async (text, options) => {
         await daemonClient.sendAgentMessage(id, text, options);
       },

packages/expo-two-way-audio/package.json

@@ -33,7 +33,6 @@
   "devDependencies": {
     "@types/jest": "^29.5.14",
     "@types/react": "^18.0.25",
-    "expo-module-scripts": "^5.0.8",
     "expo-modules-core": "^2.0.4"
   },
   "peerDependencies": {

packages/expo-two-way-audio/tsconfig.json

@@ -6,7 +6,7 @@
     "module": "esnext",
     "moduleResolution": "bundler",
     "typeRoots": [
-      "./node_modules/expo-module-scripts/ts-declarations",
+      "../../node_modules/expo-module-scripts/ts-declarations",
       "./node_modules/@types",
       "../../node_modules/@types"
     ]

packages/highlight/src/__tests__/highlighter.test.ts

@@ -1,4 +1,6 @@
 import { describe, it, expect } from "vitest";
+import { setImmediate } from "node:timers/promises";
+import { highlightCodeWithBudget, HIGHLIGHT_MAX_SOURCE_BYTES } from "../budgeted-highlighter.js";
 import type { HighlightToken } from "../types.js";
 import { highlightCode, highlightCodeInSteps, highlightLine } from "../highlighter.js";
 
@@ -420,3 +422,55 @@ describe("highlightLine", () => {
     expect(tokens).toEqual([{ text: "hello", style: null }]);
   });
 });
+
+describe("highlightCodeWithBudget", () => {
+  it("yields to IO while producing byte-identical output below the source budget", async () => {
+    const code = "const value = Math.max(42, 7);\n".repeat(3_000);
+    const expected = JSON.stringify(highlightCode(code, "file.ts"));
+    let ticks = 0;
+    let longestGap = 0;
+    let lastTick = performance.now();
+    const timer = setInterval(() => {
+      const now = performance.now();
+      longestGap = Math.max(longestGap, now - lastTick);
+      lastTick = now;
+      ticks++;
+    }, 1);
+    try {
+      const actual = await highlightCodeWithBudget(code, "file.ts", {
+        yieldToEventLoop: setImmediate,
+      });
+      await new Promise((resolve) => setTimeout(resolve, 5));
+      expect(ticks).toBeGreaterThan(1);
+      expect(longestGap).toBeLessThan(50);
+      expect(JSON.stringify(actual)).toBe(expected);
+    } finally {
+      clearInterval(timer);
+    }
+  });
+
+  it("budgets UTF-8 bytes before parsing, including multibyte text", async () => {
+    expect(
+      await highlightCodeWithBudget("é".repeat(HIGHLIGHT_MAX_SOURCE_BYTES / 2 + 1), "file.ts", {
+        yieldToEventLoop: setImmediate,
+      }),
+    ).toBeNull();
+    expect(
+      await highlightCodeWithBudget("a".repeat(HIGHLIGHT_MAX_SOURCE_BYTES + 1), "file.ts", {
+        yieldToEventLoop: setImmediate,
+      }),
+    ).toBeNull();
+  });
+
+  it("stops a parser that is cancelled between real event-loop turns", async () => {
+    const controller = new AbortController();
+    const pending = highlightCodeWithBudget(
+      "const value = Math.max(42, 7);\n".repeat(3_000),
+      "file.ts",
+      { yieldToEventLoop: setImmediate, signal: controller.signal },
+    );
+    await setImmediate();
+    controller.abort();
+    expect(await pending).toBeNull();
+  });
+});

packages/highlight/src/budgeted-highlighter.ts

@@ -0,0 +1,49 @@
+import { highlightCodeInSteps } from "./highlighter.js";
+import type { HighlightToken } from "./types.js";
+
+// Full source, rather than patch size, bounds parser and token allocation work.
+// Each token consumes a source code unit or an empty line: at most the byte cap + 1 records.
+export const HIGHLIGHT_MAX_SOURCE_BYTES = 768 * 1024;
+const SLICE_MS = 4;
+
+/**
+ * Returns null when source exceeds the budget or the request is cancelled.
+ * The host supplies a real event-loop yield (setImmediate on the daemon).
+ * Existing synchronous highlighting remains available for its existing consumers.
+ */
+export async function highlightCodeWithBudget(
+  code: string,
+  filename: string,
+  options: { yieldToEventLoop: () => Promise<void>; signal?: { readonly aborted: boolean } },
+): Promise<HighlightToken[][] | null> {
+  if (options.signal?.aborted || exceedsSourceBudget(code)) return null;
+  const steps = highlightCodeInSteps(code, filename);
+  let sliceStarted = Date.now();
+  try {
+    for (;;) {
+      if (options.signal?.aborted) return null;
+      const step = steps.next();
+      if (step.done) return step.value;
+      if (Date.now() - sliceStarted >= SLICE_MS) {
+        await options.yieldToEventLoop();
+        sliceStarted = Date.now();
+      }
+    }
+  } finally {
+    steps.return([]);
+  }
+}
+
+function exceedsSourceBudget(code: string): boolean {
+  if (code.length > HIGHLIGHT_MAX_SOURCE_BYTES) return true;
+  let bytes = 0;
+  for (const char of code) {
+    const point = char.codePointAt(0)!;
+    if (point < 0x80) bytes++;
+    else if (point < 0x800) bytes += 2;
+    else if (point < 0x10000) bytes += 3;
+    else bytes += 4;
+    if (bytes > HIGHLIGHT_MAX_SOURCE_BYTES) return true;
+  }
+  return false;
+}

packages/highlight/src/index.ts

@@ -15,3 +15,4 @@ export {
   isSyntaxThemeId,
   resolveSyntaxColors,
 } from "./themes.js";
+export { highlightCodeWithBudget, HIGHLIGHT_MAX_SOURCE_BYTES } from "./budgeted-highlighter.js";

packages/plugin/src/boundaries.test.ts

@@ -92,7 +92,12 @@ function typeErrors(code: string): string[] {
 }
 describe("plugin SDK import boundaries", () => {
   it("publishes process capabilities without their Windows implementation helpers", () => {
-    expect(Object.keys(server).sort()).toEqual(["execCommand", "spawnProcess", "terminateProcess"]);
+    expect(Object.keys(server).sort()).toEqual([
+      "defineAgentTool",
+      "execCommand",
+      "spawnProcess",
+      "terminateProcess",
+    ]);
   });
 
   it("classifies every published entry", () => {
@@ -209,3 +214,58 @@ describe("plugin panel SDK boundary", () => {
     ).toEqual([]);
   });
 });
+
+describe("plugin agent tools SDK boundary", () => {
+  it("lets a session hook attach typed tools without exposing their transport", () => {
+    expect(
+      typeErrors(`
+      import { z } from "zod";
+      import { defineAgentTool, type PluginServerContext, type AgentToolResult, type AgentToolContext, type AgentToolDefinition } from "@getpaseo/plugin/server";
+      const tool: AgentToolDefinition = defineAgentTool({
+        name: "create_issue",
+        description: "Create an issue",
+        input: z.object({ title: z.string(), count: z.string().transform(Number) }),
+        async execute(input, { agent, paseo, signal }) {
+          const count: number = input.count;
+          // @ts-expect-error input is inferred from the schema
+          input.missing;
+          return { text: agent.id + input.title, structuredContent: { count } };
+        },
+      });
+      export default function contribute(server: PluginServerContext) {
+        server.before("agent.session_open", ({ request }) => {
+          const title: string | null = request.title;
+          // @ts-expect-error labels are read-only
+          request.labels.x = "changed";
+          if (request.labels.x !== "y") return;
+          // @ts-expect-error MCP servers use the same typed transport config as saved servers
+          request.mcpServers.invalid = { type: "http", url: 42 };
+          return { ...request, tools: [...request.tools, tool], mcpServers: {
+            ...request.mcpServers, company: { type: "http", url: "https://tools.example.com/mcp" },
+          } };
+        });
+        return () => {};
+      }
+    `),
+    ).toEqual([]);
+  });
+});
+
+describe("agent session reload SDK boundary", () => {
+  it("exposes reload separately from snapshot refresh", () => {
+    expect(
+      typeErrors(`
+      import { type PluginServerContext } from "@getpaseo/plugin/server";
+      import { type PaseoAgentRefetchResult } from "@getpaseo/client";
+      async function reload(server: PluginServerContext, paseo: import("@getpaseo/client").PaseoApi) {
+        const agent = paseo.agents.ref("chosen-agent");
+        const read: PaseoAgentRefetchResult | null = await agent.refresh("read-snapshot");
+        const reopened: PaseoAgentRefetchResult | null = await agent.reload({ requestId: "reload-session" });
+        await agent.reload();
+        // @ts-expect-error reload options can grow without a positional signature change
+        await agent.reload("reload-session");
+      }
+    `),
+    ).toEqual([]);
+  });
+});

packages/plugin/src/server/agent-tools.ts

@@ -0,0 +1,39 @@
+import type { PaseoApi } from "@getpaseo/client";
+import type { z } from "zod";
+import type { PluginHookAgent } from "./lifecycle.js";
+
+export interface AgentToolContext {
+  agent: PluginHookAgent;
+  paseo: PaseoApi;
+  signal: AbortSignal;
+}
+
+export interface AgentToolResult {
+  text?: string;
+  structuredContent?: unknown;
+  isError?: boolean;
+}
+
+export interface AgentToolDefinition {
+  name: string;
+  title?: string;
+  description: string;
+  input: z.ZodType;
+  execute(input: unknown, context: AgentToolContext): AgentToolResult | Promise<AgentToolResult>;
+}
+
+export function defineAgentTool<Input extends z.ZodType>(tool: {
+  name: string;
+  title?: string;
+  description: string;
+  input: Input;
+  execute(
+    input: z.output<Input>,
+    context: AgentToolContext,
+  ): AgentToolResult | Promise<AgentToolResult>;
+}): AgentToolDefinition {
+  if (!/^[a-z][a-z0-9_]*$/.test(tool.name) || tool.name.length > 64) {
+    throw new Error(`Invalid agent tool name: ${tool.name}`);
+  }
+  return tool;
+}

packages/plugin/src/server/index.ts

@@ -24,3 +24,6 @@ export type {
 } from "./lifecycle.js";
 
 export { spawnProcess, execCommand, terminateProcess } from "./process.js";
+
+export { defineAgentTool } from "./agent-tools.js";
+export type { AgentToolDefinition, AgentToolResult, AgentToolContext } from "./agent-tools.js";

packages/plugin/src/server/lifecycle.ts

@@ -1,3 +1,4 @@
+import type { AgentToolDefinition } from "./agent-tools.js";
 import type {
   AgentPermissionRequest,
   AgentPermissionResponse,
@@ -36,7 +37,11 @@ export interface PluginSessionOpenRequest {
   cwd: string;
   reason: "create" | "resume" | "refresh" | "import";
   purpose: "interactive" | "history";
+  readonly title: string | null;
+  readonly labels: Readonly<Record<string, string>>;
+  tools: AgentToolDefinition[];
   env: Record<string, string>;
+  mcpServers: NonNullable<AgentSessionConfig["mcpServers"]>;
 }
 
 export type PluginTurnOutcome =