[BUG] Input blocked/lost while assistant is generating response

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?

Description:
When Claude is generating a response (streaming), keyboard input is either blocked or lost. I cannot type ahead while waiting for a response -
characters typed during generation don't appear in the input buffer afterward.

Expected behavior:
Input should be buffered during response generation, allowing type-ahead. Characters typed while Claude is "thinking" should appear at the prompt
when generation completes.

Actual behavior:
Input during generation is dropped. Must wait for response to complete before typing.

Environment:

• macOS (Darwin)
• Terminal: [your terminal app]
• Claude Code version: [run claude --version]

Impact:
Disrupts workflow when Claude takes time to respond. Can't compose next message while reading streaming output.

What Should Happen?

Description:
When Claude is generating a response (streaming), keyboard input is either blocked or lost. I cannot type ahead while waiting for a response -
characters typed during generation don't appear in the input buffer afterward.

Expected behavior:
Input should be buffered during response generation, allowing type-ahead. Characters typed while Claude is "thinking" should appear at the prompt
when generation completes.

Actual behavior:
Input during generation is dropped. Must wait for response to complete before typing.

Environment:

• macOS (Darwin)
• Terminal: [your terminal app]
• Claude Code version: [run claude --version]

Impact:
Disrupts workflow when Claude takes time to respond. Can't compose next message while reading streaming output.

Error Messages/Logs

Steps to Reproduce

Steps to reproduce:

1. Start Claude Code in terminal
2. Ask a question that requires a multi-paragraph response (e.g., "explain how TCP works")
3. While Claude is streaming the response, start typing your next message
4. Wait for response to complete
5. Observe: typed characters are not in the input buffer

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.20 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

kitten is is terminal emulator.