[BUG] Terminal UI freezes/hangs significantly after running `/plan` command (macOS)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When running the /plan command inside an active Claude Code session, the terminal interface freezes completely. Although the UI updates to say "Already in plan mode. No plan written yet.", the prompt becomes unresponsive. I cannot type any text or execute further commands.

The freeze duration varies:

• Sometimes it recovers after several minutes, allowing typing again.
• Other times it remains frozen indefinitely, requiring me to kill the terminal/process.

This behavior occurs even though the initial launch of claude works perfectly fine.

What Should Happen?

After running /plan, the CLI should display the status message (e.g., "Already in plan mode") and immediately return focus to the input prompt, allowing me to continue typing without delay.

Error Messages/Logs

No crash dump occurs; the UI simply locks up. Here is the terminal state at the moment of the freeze:


[...Startup logs redacted...]

❯ /plan
  ⎿  Already in plan mode. No plan written yet.

────────────────────────────────────────────────────────────────────────────────
❯ 
────────────────────────────────────────────────────────────────────────────────
[Status line redacted]

Steps to Reproduce

1. Open terminal (Tested on iTerm2 and Ghostty on macOS).
2. Launch Claude Code: claude.
3. Ensure you are in Plan Mode (my session defaults to it).
4. Type /plan into the prompt and press Enter.
5. Observe that the UI updates to show the status message, but the cursor/input line becomes unresponsive for minutes or indefinitely.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.17

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

• Claude Code Version: 2.1.27
• OS: macOS
• Terminals: Reproduced in both iTerm2 and Ghostty.
• Context: I have a significant number of custom hooks and skills running at startup.
• Observation: The session is already in Plan Mode before running the command. The freeze happens specifically when invoking the command while already in that mode.