diff --git a/README.md b/README.md
index 16c6b9e6..2889f608 100644
--- a/README.md
+++ b/README.md
@@ -93,6 +93,9 @@ Skill 正文通过原生用户消息或工具结果进入正常 Session 历史
 > [!IMPORTANT]
 > 默认安装是安静的：不改主题、不绑定 Provider 或模型、不开启下一步预测，也不执行 post-edit 命令。Capability discovery 默认 `explicit`；只有用户通过 `/openpi-setup` 选择 `adaptive` 后，模型才会常驻看到一个小型发现网关并可自主加载额外能力。
 
+> [!TIP]
+> Windows 用户如果在输入 `/lo` 等斜杠命令时看到旧的补全行残留，OpenPI 会在当前交互式会话中为未显式配置 `terminal.clearOnShrink` 的 `regular` TUI 启用收缩清理。该兜底不会修改 Pi 的全局或项目偏好；显式的 `terminal.clearOnShrink` 值会被保留。需要永久选择 TUI 模式时，请使用 Pi 原生 `/settings`、`settings.json` 或 `--tui-mode`。
+
 ```text
 /openpi-setup
 ```
diff --git a/SETUP.md b/SETUP.md
index 9fe26edb..be0c364f 100644
--- a/SETUP.md
+++ b/SETUP.md
@@ -14,6 +14,31 @@ pi install git:github.com/openpi-dev/openpi
 
 Pi installs the package dependencies automatically. Restart Pi or run `/reload` after installation.
 
+### Windows terminal compatibility
+
+On Windows, OpenPI detects the stale autocomplete-row redraw problem in Pi's
+`regular` (main-screen) renderer. When neither global nor project settings
+explicitly sets `terminal.clearOnShrink`, it enables Pi's supported
+`clear-on-shrink` behavior for the current renderer only. This prevents old
+slash-command autocomplete rows from making commands look duplicated without
+changing a global or project preference.
+
+An explicit `terminal.clearOnShrink` value is always preserved, including
+`false`. OpenPI also leaves the selected `tuiMode` unchanged; use Pi's native
+`/settings`, `settings.json`, or the `--tui-mode` flag when you want to choose
+that mode explicitly.
+
+For example, Pi's alternate-screen renderer remains available from `/settings`
+or `settings.json`:
+
+```json
+{
+  "tuiMode": "fullscreen"
+}
+```
+
+The compatibility behavior is tracked in [openpi#407](https://github.com/openpi-dev/openpi/issues/407).
+
 ## fd, rg, and read-only git tools
 
 The `file-search` extension registers `fd` and `rg` as model tools, and `git-read` registers `git_show`, `git_diff`, and `git_log` (read-only git inspection). They stay outside an ordinary parent turn until the user explicitly asks to use `fd`/`rg`/git history, or structured file search, or the model loads the `search` group through `openpi_load_tools`. Entering or restoring Plan Mode is a runtime-safety exception: it loads `search` for that Session so diff investigation can use the structured Git boundary. The gateway is shown after an explicit OpenPI-capability request, or remains visible when the user opts into adaptive discovery; child sessions may still receive these tools through the reviewed child-safe allowlist (the read-only git tools let reviewer/advisor subagents inspect diffs, which a bash-free tool boundary otherwise excludes). No setup is normally needed: at startup `fd`/`rg` silently use a system-installed binary (`fd`/`fdfind` and `rg`) when available, or an existing binary in the agent's private managed bin directory (`~/.pi/agent/bin`). Only when neither exists does it download an official release binary (macOS/Linux, arm64/x64, over HTTPS) into that directory — a persistent cache that survives package updates — and show a one-time notification. If your platform is unsupported, install `fd` and `rg` with your package manager and restart Pi. The git tools require a system `git`.
diff --git a/extensions/windows-tui-compatibility/index.ts b/extensions/windows-tui-compatibility/index.ts
new file mode 100644
index 00000000..ad040d6d
--- /dev/null
+++ b/extensions/windows-tui-compatibility/index.ts
@@ -0,0 +1,135 @@
+import type {
+  ExtensionAPI,
+  ExtensionContext,
+} from "@earendil-works/pi-coding-agent";
+
+interface TuiSettings {
+  terminal?: {
+    clearOnShrink?: boolean;
+  };
+}
+
+interface TuiSettingsManager {
+  getGlobalSettings(): TuiSettings;
+  getProjectSettings(): TuiSettings;
+  drainErrors?(): readonly unknown[];
+}
+
+type TuiSettingsManagerFactory = (
+  cwd: string,
+) => TuiSettingsManager | Promise<TuiSettingsManager>;
+
+const WIDGET_KEY = "openpi-windows-tui-compatibility";
+
+/**
+ * The main-screen renderer can leave stale autocomplete rows on Windows.
+ * Keep the workaround limited to interactive Windows sessions so RPC/print
+ * users and non-Windows terminals are unaffected.
+ */
+export function shouldInstallWindowsTuiCompatibility(
+  platform: NodeJS.Platform,
+  mode: ExtensionContext["mode"],
+) {
+  return platform === "win32" && mode === "tui";
+}
+
+export function shouldEnableWindowsClearOnShrink(options: {
+  platform: NodeJS.Platform;
+  mode: ExtensionContext["mode"];
+  globalClearOnShrink?: boolean;
+  projectClearOnShrink?: boolean;
+}) {
+  return (
+    shouldInstallWindowsTuiCompatibility(options.platform, options.mode) &&
+    options.globalClearOnShrink === undefined &&
+    options.projectClearOnShrink === undefined
+  );
+}
+
+function readClearOnShrinkSettings(settingsManager: TuiSettingsManager) {
+  const globalSettings = settingsManager.getGlobalSettings();
+  const projectSettings = settingsManager.getProjectSettings();
+  return {
+    globalClearOnShrink: globalSettings.terminal?.clearOnShrink,
+    projectClearOnShrink: projectSettings.terminal?.clearOnShrink,
+  };
+}
+
+/**
+ * Register the Windows renderer workaround.
+ *
+ * Pi exposes the renderer to widget factories, but not as a direct property
+ * on ExtensionContext. The zero-height widget lets us apply the supported
+ * renderer setting without replacing OpenPI's header, footer, or editor.
+ *
+ * The renderer setting is deliberately session-local. Pi's SettingsManager
+ * setters persist global preferences, so this compatibility extension only
+ * reads the existing clear-on-shrink settings and never changes tuiMode or
+ * terminal preferences on the user's behalf.
+ */
+export function registerWindowsTuiCompatibility(
+  pi: ExtensionAPI,
+  platform: NodeJS.Platform,
+  settingsManagerFactory?: TuiSettingsManagerFactory,
+) {
+  let activeUi: ExtensionContext["ui"] | undefined;
+
+  const cleanup = () => {
+    const ui = activeUi;
+    activeUi = undefined;
+    try {
+      ui?.setWidget(WIDGET_KEY, undefined);
+    } catch {
+      // The renderer may already be gone during shutdown.
+    }
+  };
+
+  pi.on("session_start", async (_event, ctx) => {
+    cleanup();
+    if (!shouldInstallWindowsTuiCompatibility(platform, ctx.mode)) return;
+
+    let enableClearOnShrink = false;
+    if (settingsManagerFactory) {
+      try {
+        const settingsManager = await settingsManagerFactory(ctx.cwd);
+        const settings = readClearOnShrinkSettings(settingsManager);
+        const settingsErrors = settingsManager.drainErrors?.() ?? [];
+        enableClearOnShrink =
+          settingsErrors.length === 0 &&
+          shouldEnableWindowsClearOnShrink({
+            platform,
+            mode: ctx.mode,
+            ...settings,
+          });
+      } catch {
+        // Settings reads must never prevent the OpenPI session from starting.
+      }
+    }
+
+    activeUi = ctx.ui;
+    ctx.ui.setWidget(
+      WIDGET_KEY,
+      (tui) => {
+        // The renderer can be replaced at runtime when the user switches TUI
+        // modes, so apply this when the factory receives the active renderer.
+        if (tui.mode === "regular" && enableClearOnShrink) {
+          tui.setClearOnShrink(true);
+        }
+        return {
+          render: () => [],
+          invalidate() {},
+        };
+      },
+      { placement: "belowEditor" },
+    );
+  });
+
+  pi.on("session_shutdown", cleanup);
+}
+
+export default function windowsTuiCompatibility(pi: ExtensionAPI) {
+  registerWindowsTuiCompatibility(pi, process.platform, async (cwd) => {
+    const { SettingsManager } = await import("@earendil-works/pi-coding-agent");
+    return SettingsManager.create(cwd);
+  });
+}
diff --git a/tests/extensions/windows-tui-compatibility/index.test.ts b/tests/extensions/windows-tui-compatibility/index.test.ts
new file mode 100644
index 00000000..4c95d34e
--- /dev/null
+++ b/tests/extensions/windows-tui-compatibility/index.test.ts
@@ -0,0 +1,205 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import type {
+  ExtensionAPI,
+  ExtensionContext,
+} from "@earendil-works/pi-coding-agent";
+import type { Component, TUI } from "@earendil-works/pi-tui";
+import {
+  registerWindowsTuiCompatibility,
+  shouldEnableWindowsClearOnShrink,
+  shouldInstallWindowsTuiCompatibility,
+} from "../../../extensions/windows-tui-compatibility/index.ts";
+
+type WidgetFactory = (
+  tui: TUI,
+  theme: unknown,
+) => Component & { dispose?(): void };
+
+function createHarness(
+  platform: NodeJS.Platform,
+  mode: ExtensionContext["mode"] = "tui",
+  settingsManagerFactory?: Parameters<
+    typeof registerWindowsTuiCompatibility
+  >[2],
+) {
+  const hooks = new Map<
+    string,
+    (event: unknown, ctx: ExtensionContext) => unknown
+  >();
+  let widgetFactory: WidgetFactory | undefined;
+  let widgetCleared = false;
+  const notifications: string[] = [];
+
+  const pi = {
+    on(event: string, handler: unknown) {
+      hooks.set(
+        event,
+        handler as (event: unknown, ctx: ExtensionContext) => unknown,
+      );
+    },
+  } as unknown as ExtensionAPI;
+
+  const ctx = {
+    cwd: "C:\\project",
+    mode,
+    hasUI: mode === "tui",
+    ui: {
+      setWidget(_key: string, content: WidgetFactory | undefined) {
+        if (content) widgetFactory = content;
+        else {
+          widgetFactory = undefined;
+          widgetCleared = true;
+        }
+      },
+      notify(message: string) {
+        notifications.push(message);
+      },
+    },
+  } as unknown as ExtensionContext;
+
+  registerWindowsTuiCompatibility(pi, platform, settingsManagerFactory);
+
+  return {
+    ctx,
+    emit(event: string) {
+      return hooks.get(event)?.({}, ctx);
+    },
+    mount(tui: TUI) {
+      return widgetFactory?.(tui, {});
+    },
+    get widgetFactory() {
+      return widgetFactory;
+    },
+    get widgetCleared() {
+      return widgetCleared;
+    },
+    get notifications() {
+      return notifications;
+    },
+  };
+}
+
+test("installs only for interactive Windows sessions", () => {
+  assert.equal(shouldInstallWindowsTuiCompatibility("win32", "tui"), true);
+  assert.equal(shouldInstallWindowsTuiCompatibility("linux", "tui"), false);
+  assert.equal(shouldInstallWindowsTuiCompatibility("win32", "rpc"), false);
+
+  assert.equal(
+    shouldEnableWindowsClearOnShrink({ platform: "win32", mode: "tui" }),
+    true,
+  );
+  assert.equal(
+    shouldEnableWindowsClearOnShrink({
+      platform: "win32",
+      mode: "tui",
+      globalClearOnShrink: false,
+    }),
+    false,
+  );
+  assert.equal(
+    shouldEnableWindowsClearOnShrink({
+      platform: "win32",
+      mode: "tui",
+      globalClearOnShrink: true,
+    }),
+    false,
+  );
+  assert.equal(
+    shouldEnableWindowsClearOnShrink({
+      platform: "win32",
+      mode: "tui",
+      projectClearOnShrink: false,
+    }),
+    false,
+  );
+
+  const linux = createHarness("linux");
+  linux.emit("session_start");
+  assert.equal(linux.widgetFactory, undefined);
+});
+
+test("enables clear-on-shrink for regular TUI but not fullscreen", async () => {
+  const harness = createHarness("win32", "tui", async () => ({
+    getGlobalSettings: () => ({}),
+    getProjectSettings: () => ({}),
+  }));
+  await harness.emit("session_start");
+
+  const clearOnShrink: boolean[] = [];
+  harness.mount({
+    mode: "regular",
+    setClearOnShrink(enabled: boolean) {
+      clearOnShrink.push(enabled);
+    },
+    requestRender(force?: boolean) {
+      assert.equal(force, undefined);
+    },
+  } as TUI);
+  assert.deepEqual(clearOnShrink, [true]);
+
+  clearOnShrink.length = 0;
+  harness.mount({
+    mode: "fullscreen",
+    setClearOnShrink(enabled: boolean) {
+      clearOnShrink.push(enabled);
+    },
+    requestRender(force?: boolean) {
+      assert.equal(force, undefined);
+    },
+  } as TUI);
+  assert.deepEqual(clearOnShrink, []);
+});
+
+test("keeps the workaround session-local and respects explicit clear-on-shrink", async () => {
+  const writes: string[] = [];
+  const explicit = createHarness("win32", "tui", async () => ({
+    getGlobalSettings: () => ({ terminal: { clearOnShrink: false } }),
+    getProjectSettings: () => ({}),
+    drainErrors: () => [],
+  }));
+  await explicit.emit("session_start");
+
+  const clearOnShrink: boolean[] = [];
+  explicit.mount({
+    mode: "regular",
+    setClearOnShrink(enabled: boolean) {
+      writes.push("clear-on-shrink");
+      clearOnShrink.push(enabled);
+    },
+    requestRender() {},
+  } as TUI);
+
+  assert.deepEqual(clearOnShrink, []);
+  assert.deepEqual(explicit.notifications, []);
+  assert.deepEqual(writes, []);
+});
+
+test("fails closed when settings cannot be read", async () => {
+  const harness = createHarness("win32", "tui", async () => {
+    throw new Error("malformed settings");
+  });
+  await harness.emit("session_start");
+
+  const clearOnShrink: boolean[] = [];
+  harness.mount({
+    mode: "regular",
+    setClearOnShrink(enabled: boolean) {
+      clearOnShrink.push(enabled);
+    },
+    requestRender() {},
+  } as TUI);
+
+  assert.deepEqual(clearOnShrink, []);
+});
+
+test("cleans up the compatibility widget on shutdown", () => {
+  const harness = createHarness("win32");
+  harness.emit("session_start");
+  assert.ok(harness.widgetFactory);
+
+  harness.emit("session_shutdown");
+
+  assert.equal(harness.widgetFactory, undefined);
+  assert.equal(harness.widgetCleared, true);
+});