Windows: Cannot type in terminal until pressing Enter after v2.1.31 update (regression)

[reconunpro]

Preflight Checklist

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

What's Wrong?

When Claude Code is launched with an initial prompt argument (claude "any prompt"), the terminal input freezes — the user cannot type until pressing Enter to "unstick" it. Launching claude without arguments works fine.

Trigger: Passing a CLI prompt argument

claude "any prompt"    → FREEZES (must press Enter to unstick)
claude                 → WORKS (always)

This is a race condition that triggers more reliably in directories with heavier project context (CLAUDE.md files, .claude/ settings, git repos). In any project directory it freezes 100% of the time. In minimal directories it can occasionally succeed.

What Should Happen?

After processing the initial prompt argument, keyboard input should work immediately without needing to press Enter to activate the input field.

Error Messages/Logs

No error messages — the hook and prompt processing complete successfully.
Debug logs show normal execution; the issue is in stdin/readline state after processing.

Steps to Reproduce

1. Open any terminal on Windows (PowerShell, Git Bash, cmd)
2. Navigate to any project directory with a CLAUDE.md file
3. Run claude "hello world"
4. Wait for Claude to respond to the initial prompt
5. Try to type — nothing appears in the input field
6. Press Enter — keyboard input now works normally

Minimal reproduction (fresh terminal, no hooks/plugins needed):

cd <any-project-directory>
claude "a"
# Stdin is frozen — press Enter to unstick

What's NOT the cause (ruled out with 18+ tests)

Suspected Cause	How Ruled Out
SessionStart hooks	Disabled all hooks — freeze persists with claude "prompt"
Any hooks/plugins/statusLine	Emptied all hooks.json, disabled plugins — freeze persists
Console mode corruption	Win32 GetConsoleMode/SetConsoleMode save/restore — freeze persists
Console input buffer	FlushConsoleInputBuffer — freeze persists
PowerShell -Command mode	Freeze happens with manually typed commands too
Terminal emulator	Reproduces in Windows Terminal, standalone PowerShell
Interactive input before claude	Red herring — always co-occurred with prompt argument

What DOES work (no freeze)

Command	Result
claude (no args)	Works — always
claude --resume	Works
claude -c	Works
claude --verbose	Works

Non-prompt flags follow a different code path and don't trigger the race condition.

Claude Model

Claude Opus 4

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.30

Claude Code Version

2.1.34 (Claude Code)

Platform

Claude Max (Pro/Team subscription)

Operating System

Microsoft Windows 11 Pro (10.0.26200)

Terminal/Shell

Windows Terminal 1.23.20211.0 / PowerShell 5.1.26100.7705

Additional Information

Node.js version: v24.11.1

Related Issues (all closed as NOT_PLANNED):

• [BUG] Cannot type in Claude Code on Windows bash until pressing Ctrl+V #11581 - Cannot type until Ctrl+V on Windows bash
• [Bug] Windows Terminal Input Stream Loss After Command Execution #10736 - Windows Terminal Input Stream Loss
• [BUG] Cant type anymore in claude code #8566 - Can't type anymore in Claude Code

Likely root cause: Race condition between Node.js stdin/readline initialization and initial prompt processing on Windows. When claude processes a CLI prompt argument, stdin setup doesn't complete correctly before entering interactive mode.

Workaround: Always launch claude without prompt arguments. Type the initial prompt interactively after claude starts.

[github-actions]

Found 3 possible duplicate issues:

1. Keyboard input not working in v2.1.30 (Windows) #22906
2. CLI keyboard input broken in SSH terminal sessions after 2.1.30 update (Windows OpenSSH + Termius iOS) #22948
3. [BUG] Windows 10/11 PowerShell/CMD claude -c doesn't accept keyboard input claude (without -c) works fine Pressing Esc sometimes fixes it #22949

This issue will be automatically closed as a duplicate in 3 days.

• If your issue is a duplicate, please close it and 👍 the existing issue instead
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🤖 Generated with Claude Code

[Junik-Choi]

your my god. thank you a lot...

[ykrzy]

Same issue. Confirmed this is triggered by SessionStart hook execution.

Test Case	Result
Plugin with hooks disabled	Works
Plugin enabled, empty hooks.json	Works
SessionStart hook registered but non-matching matcher	Works
SessionStart hook executes	Freezes (Enter unfreezes)
SessionStart with simple echo {"continue":true}	Freezes
SessionStart with exit 1 (failing command)	Freezes
SessionStart with no output (silent exit)	Freezes
SessionStart with async response	Freezes
SessionStart with 0.001s timeout	Freezes
SessionStart defined in project settings (not plugin)	Freezes
Other hooks (Stop, UserPromptSubmit, PostToolUse)	Work

The freeze occurs when any SessionStart hook executes, regardless of:

• Command used (node, echo, exit)
• Output format (sync, async, none)
• Exit code (success or failure)
• Timeout value

Debug logs show the hook completes successfully:

Hook SessionStart:startup (SessionStart) success: {"continue":true}

But something in Claude Code's post-hook handling for SessionStart loses input focus.

[joeydangelo]

Experiencing the same

[reconunpro]

Update: Additional trigger identified — CLI prompt argument (v2.1.34)

After extensive debugging (18+ tests), I've identified that passing an initial prompt as a CLI argument reliably triggers the stdin freeze on Windows.

Reproduction (100% reliable)

In any PowerShell or terminal window on Windows:

claude "any prompt here"    → STDIN FREEZES (must press Enter to unstick)
claude                      → WORKS FINE (always)

This reproduces in a completely fresh terminal window with zero prior commands — no hooks, no plugins, no scripts involved.

Key findings

Command	Result
claude	Works — always, every directory, every scenario
claude "a"	Freezes — even a single character prompt
claude "hello world"	Freezes
claude --resume	Works — flags without prompt are fine
claude -c	Works
claude --verbose	Works

Race condition with project context

The freeze triggers more reliably in directories with heavier project context (CLAUDE.md files, .claude/ settings, git repos). In minimal directories it can occasionally succeed, but in any project directory it freezes 100% of the time.

What's NOT the cause (ruled out)

• Hooks/plugins/statusLine — emptied all hooks.json files, disabled all plugins, removed statusLine — freeze persists when using claude "prompt"
• Console mode corruption — tried Win32 GetConsoleMode/SetConsoleMode save/restore
• Console input buffer — tried FlushConsoleInputBuffer
• PowerShell -Command mode — freeze happens with manually typed commands in interactive PowerShell too
• Terminal emulator — not specific to Windows Terminal
• Interactive input before claude — initially suspected, turned out to be a red herring (always co-occurred with the prompt argument in our test setup)

Likely cause

Race condition between Node.js stdin/readline initialization and initial prompt processing on Windows. When claude processes a CLI prompt argument, something in the stdin setup doesn't complete correctly before entering interactive mode. Non-prompt flags (--resume, -c, --verbose) don't trigger it because they likely follow a different code path.

Workaround

Always launch claude without prompt arguments. Type the initial prompt interactively after claude starts.

Environment

• OS: Microsoft Windows 11 Pro (10.0.26200)
• Shell: PowerShell 5.1.26100.7705
• Terminal: Windows Terminal 1.23.20211.0
• Node.js: v24.11.1
• Claude Code: v2.1.34