[BUG] Bash tool commands unexpectedly queued to background, causing conversation stall

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:

During a normal conversation, Bash tool commands started being routed to background tasks instead of executing inline. This caused a ~30 minute stall as the assistant repeatedly attempted to retrieve output from tasks that were timing out.

Environment:

• Platform: Linux (Debian 13, kernel 6.12.57)
• Claude Code version: (2.0.76)
• Model: claude-opus-4-5-20251101

Notes:

• No run_in_background: true parameter was set
• Earlier commands in the same session worked normally
• Issue persisted across multiple retry attempts

What Should Happen?

Simple, fast commands should execute inline and return output directly, not be queued to background.

Error Messages/Logs

Commands returned messages like:
  Command running in background with ID: b34531e. Output is being written to: /tmp/claude/-home-moe/tasks/b34531e.output

  When attempting to retrieve with TaskOutput:
  <retrieval_status>timeout</retrieval_status>
  <status>running</status>

  The output files in /tmp/claude/-home-moe/tasks/ were empty or didn't exist.

Steps to Reproduce

Steps to reproduce:

1. Normal conversation with several successful Bash tool calls
2. At some point, subsequent Bash calls started returning background task IDs instead of executing
3. Commands as simple as ls -la ~/.config/kitty/sessions/ were affected

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.0.76

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other

Additional Information

QTerminal 2.1.0
xfce4 4.2

transcript.txt

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