[BUG]

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?

Claude Code processes frequently spike to 100%+ CPU and won't stop

Environment:

• macOS Darwin 24.5.0
• Node v20.19.2
• Claude Code version: v2.0.25

Symptoms:

• Multiple claude processes spike to 80-120% CPU
• Processes get stuck in an endless loop and don't terminate naturally
• Terminal not responsive to ctrl + C or any input
• Happens frequently during normal usage
• Requires kill -9 to stop

Examples from today:

• PID 24024: 120% CPU for 22+ minutes
• PID 34494: 94% CPU for 4+ minutes (just started but will continue if not killed)
• Combined 214% CPU usage (2+ cores maxed)

Impact:

• System becomes sluggish / terminal crashes
• Interrupts workflow
• requires stopping processes and loosing progress / context

What Should Happen?

Should be able to stop process with Crtl + C / escape
Ideally shouldn't spike or stop itself and come back with error message / suggestions to improve behavior

Error Messages/Logs

This is the issue no errors messages are presented it just keeps running and it's difficult to know if it is working or stuck....difficult to diagnose....

Steps to Reproduce

open several terminal windows / sessions - even ones that are not active....

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude Code v2.0.25 Sonnet 4.5 · Claude Max

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

These types of errors have become more frequent with V2 - V1 was more way more stable. Perhaps less agents working in the background and less orchestration than we have now. It's difficult to assess if V2 is actually an improvement over V1 due to the frequent crashes with V2. It may be faster, it may be smarter but that is difficult to see as it crashes out sooner. V1 would crash in terminals with very long history but that could be expected. This new behavior is unexpected and unpredictable