Description

Typing /new or /clear in the CLI shows the 3-option confirmation prompt ([1] Approve Once, [2] Always Approve, [3] Cancel), but then freezes permanently. The user cannot type a choice — input() never returns.

Root Cause

_confirm_destructive_slash() in cli.py:8651 calls _prompt_text_input("Choice [1/2/3]: "). Slash commands are dispatched from process_loop (a daemon thread, cli.py:12749), not the main thread.

_prompt_text_input (cli.py:6018) checks threading.current_thread() is threading.main_thread(). When false, it falls back to direct input():

else:
    _ask()  # calls input() directly

But prompt_toolkit owns stdin in raw mode on the main thread. input() on a daemon thread is blocked waiting for stdin that ptk has already captured. This is a permanent hang.

What Was Tried

Attempted to use asyncio.run_coroutine_threadsafe(run_in_terminal(_ask), loop):

1. run_in_terminal(_ask) fails because the daemon thread has no event loop: RuntimeError: There is no current event loop in thread (Python 3.11 ensure_future requires one)
2. Adding asyncio.set_event_loop(loop) before calling run_in_terminal fixes the RuntimeError, and input() now works — but then the CLI exits after choice selection (something in run_in_terminal / prompt_toolkit state restoration causes the exit)

Suggested Fix Direction

The destructive slash confirmation should probably not use input() at all from the daemon thread. Instead, it could:

• Route the prompt through prompt_toolkit's composer/buffer system (like clarify does with _clarify_state)
• Or use event.app.run_in_terminal() from the main thread directly, by deferring the confirmation prompt to the main thread via call_soon_threadsafe
• Or handle /new inline on the UI thread like /model already does (line 11108)

Environment

• macOS 26.4.1, Python 3.11.15
• Hermes CLI (not TUI)
• prompt_toolkit 3.x
• Reproducible: always