diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fe682bfd4..25e1a490a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -223,6 +223,20 @@ jobs:
         working-directory: tui
         run: python3 scripts/pty_smoke.py
 
+      - name: Set up Python for ConPTY smoke test
+        if: runner.os == 'Windows'
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.13'
+
+      - name: Test TUI in a real ConPTY terminal
+        if: runner.os == 'Windows'
+        working-directory: tui
+        shell: pwsh
+        run: |
+          python -m pip install --disable-pip-version-check pywinpty==3.0.5
+          python scripts/conpty_smoke.py
+
       - name: Build TUI
         working-directory: tui
         run: bun run build
diff --git a/tui/scripts/conpty_smoke.py b/tui/scripts/conpty_smoke.py
new file mode 100644
index 000000000..d50c276fd
--- /dev/null
+++ b/tui/scripts/conpty_smoke.py
@@ -0,0 +1,127 @@
+#!/usr/bin/env python3
+"""Exercise the TUI through the native Windows ConPTY boundary."""
+
+from __future__ import annotations
+
+import os
+import shutil
+import sys
+import time
+from pathlib import Path
+from typing import Any
+
+ROOT = Path(__file__).resolve().parents[1]
+ENTER_ALT_SCREEN = "\x1b[?1049h"
+LEAVE_ALT_SCREEN = "\x1b[?1049l"
+
+
+def _read(process: Any, timeout: float) -> str:
+    output: list[str] = []
+    deadline = time.monotonic() + timeout
+    while time.monotonic() < deadline:
+        try:
+            chunk = process.read(65_536)
+        except EOFError:
+            break
+        if chunk:
+            output.append(chunk)
+        else:
+            time.sleep(0.01)
+    return "".join(output)
+
+
+def _wait_for(process: Any, needle: str, timeout: float) -> str:
+    output: list[str] = []
+    deadline = time.monotonic() + timeout
+    while needle not in "".join(output) and time.monotonic() < deadline:
+        output.append(_read(process, min(0.1, deadline - time.monotonic())))
+    text = "".join(output)
+    if needle not in text:
+        raise AssertionError(f"terminal output did not contain {needle!r}")
+    return text
+
+
+def _wait_for_exit(process: Any, timeout: float) -> int:
+    deadline = time.monotonic() + timeout
+    while process.isalive() and time.monotonic() < deadline:
+        time.sleep(0.05)
+    if process.isalive():
+        process.close(force=True)
+        raise AssertionError("TUI did not exit after Ctrl+C")
+    return int(process.exitstatus or 0)
+
+
+def main() -> int:
+    if os.name != "nt":
+        raise SystemExit("ConPTY smoke test requires Windows")
+
+    # PyWinPTY's high-level reader otherwise blocks when ConPTY has no new
+    # bytes, preventing bounded CI assertions.
+    os.environ["PYWINPTY_BLOCK"] = "0"
+    from winpty import PtyProcess  # type: ignore[import-not-found]
+    from winpty.enums import Backend  # type: ignore[import-not-found]
+
+    bun = shutil.which("bun")
+    if not bun:
+        raise SystemExit("bun is required")
+    env = {
+        **os.environ,
+        "NANOBOT_TUI_WS_URL": "ws://127.0.0.1:9/ws",
+        "NANOBOT_TUI_API_URL": "",
+        "NANOBOT_TUI_API_TOKEN": "",
+        "NANOBOT_TUI_MODEL": "test/model",
+        "NANOBOT_TUI_WORKSPACE": r"C:\nanobot-tui-conpty",
+        "NANOBOT_TUI_VERSION": "test",
+        "NANOBOT_TUI_ACCESS": "workspace access",
+        "NANOBOT_TUI_THEME": "dark",
+        # Headless ConPTY has no terminal emulator to answer optional OSC 66
+        # width probes. Keep this smoke test focused on application behavior.
+        "OPENTUI_FORCE_EXPLICIT_WIDTH": "false",
+    }
+    process = PtyProcess.spawn(
+        [bun, "src/index.ts"],
+        cwd=str(ROOT),
+        env=env,
+        dimensions=(24, 80),
+        backend=Backend.ConPTY,
+    )
+
+    output: list[str] = []
+    try:
+        output.append(_wait_for(process, ENTER_ALT_SCREEN, 15))
+        for grapheme in "abc中文🙂":
+            process.write(grapheme)
+            time.sleep(0.03)
+        output.append(_read(process, 0.5))
+
+        process.setwinsize(18, 42)
+        resized = _read(process, 0.75)
+        output.append(resized)
+        if "\x1b[18;" not in resized or ";42H" not in resized:
+            raise AssertionError("TUI did not repaint to the resized ConPTY dimensions")
+
+        # First Ctrl+C clears the draft. The second exits the app and must
+        # restore the alternate screen without an unhandled exception.
+        process.sendcontrol("c")
+        output.append(_read(process, 0.2))
+        process.sendcontrol("c")
+        output.append(_wait_for(process, LEAVE_ALT_SCREEN, 8))
+        exit_code = _wait_for_exit(process, 8)
+    finally:
+        if process.isalive():
+            process.close(force=True)
+
+    text = "".join(output)
+    if exit_code != 0:
+        raise AssertionError(f"TUI exited with status {exit_code}")
+    for glyph in "abc中文🙂":
+        if glyph not in text:
+            raise AssertionError(f"TUI did not render committed input {glyph!r}")
+    if "Traceback" in text or "Task exception was never retrieved" in text:
+        raise AssertionError("TUI emitted an exception during shutdown")
+    print("ConPTY smoke test passed: Unicode input, resize, and terminal restoration")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())