[BUG] SIGKILL crashes 5-10x daily since Opus 4.6 (v24.13.0)

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?

Since upgrading to Opus 4.6, Claude Code is terminated by SIGKILL
multiple times per day (5-10 crashes). This did not happen on previous
model versions with the same hardware and workflow.

The crash is non-graceful — no warning, no cleanup, no chance to save
state. This has resulted in data loss when crashes occur mid-edit
across multiple files.

Impact

• Data loss: Crashes during multi-file edits leave working tree in a

partially modified state with no rollback

• Workflow disruption: 5-10 restarts per day, losing full conversation

context each time

Environment

• Claude Code version: v24.13.0
• Model: Opus 4.6
• OS: Pop!_OS / Linux 6.17.9-76061709-generic
• Shell: fish
• Node: v24.13.0

Not OOM

Verified that the Linux OOM killer is not responsible:

sudo dmesg | grep -i "oom\|killed" | tail -20 # empty
journalctl -k --since "today" | grep -i "oom\|killed" | tail -20 #
empty

No kernel-level memory kill entries exist, which rules out system
resource exhaustion.

What Should Happen?

Claude Code should either stay alive or exit gracefully with a clear
error message, not be killed by SIGKILL with no warning.

Error Messages/Logs

fish: Job 1, 'claude' terminated by signal SIGKILL (Forced quit)

Steps to Reproduce

Happens during normal CLI usage — editing files, running queries,
subagent tasks

• More frequent during longer sessions (1-2 hours)
• More frequent during bulk operations (editing many files, large

diffs in context)

• Happens regardless of whether "don't ask" mode is enabled

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

4.5

Claude Code Version

24.13.0

Platform

Anthropic API

Operating System

Other Linux

Terminal/Shell

Other

Additional Information

<img width="829" height="737" alt="Image" src="https://github.com/user-attachments/assets/1f2ee69e-0e52-43ad-b218-9d598b8d7db8" />