Claude Code is operating very slowly

Claude Code CLI - Severe Performance Issues (18+ seconds response time)

Hello Anthropic Support Team,
I'm experiencing severe performance issues with Claude Code CLI that make it unusable. Here are the details:
Account Information:

Subscription: Claude MAX plan
Tool: Claude Code CLI (npm package @anthropic-ai/claude-code)
Version: 1.0.51

Issue Description:
Claude Code freezes and takes 18+ seconds to respond to simple queries. The terminal becomes completely unresponsive during this time - I cannot even type. Task Manager shows the process is using minimal resources (9.4% CPU, 879MB RAM), but responses are extremely slow.
Symptoms:

Response time: 18+ seconds for ~160 tokens
Terminal freezes completely while waiting for responses
Network traffic is minimal (0.1 MB/s) but active
Cannot interrupt or type during the wait
Eventually works but is too slow to be usable

Troubleshooting Steps Already Taken:

Complete uninstall and reinstall of Claude Code
Cleared all cache and config files
Tested in different directories
Disabled Windows Defender real-time protection
Tested network connection (internet is working fine)
Fresh install after complete cleanup of all Claude-related files

Additional Context:

Also experienced OAuth authentication errors earlier ("Missing client_id parameter")
Issue persists across different times of day
Web interface at claude.ai works normally
Other internet services work fine
Started experiencing issues on July 13, 2025

System Information:

OS: Windows 11
Node.js: v24.1.0 (also have WSL environment)
Internet: Stable broadband connection

This appears to be a server-side issue as local resources are not constrained. The extreme response times (18+ seconds) suggest API server overload or regional routing issues.

Could you please investigate this issue? Claude Code is currently unusable due to these performance problems.

Thank you.

I found the issue, somehow CC wrote itself a huge and bad config file - Maybe this will help some other people:

"● Critical Issue Found and Fixed!

Yes, there was a massive 1.3MB config file at .claude/settings.local.json that contained thousands of hook definitions! This was definitely the root cause of your freezing issues.

What I fixed:

1. Replaced the bloated settings.local.json - It had thousands of hook entries causing the PreToolUse:Bash freezes
2. Streamlined permissions - Only essential commands are allowed now
3. Removed all MCP server references - No more mcp__multi-ai-collab__ or mcp__context7__ entries

Files now fixed:

• ✅ ~/.claude.json - Cleaned up duplicates, fixed trust dialog
• ✅ ~/.config/claude-code/settings.json - Disabled MCP and hooks globally
• ✅ .claude-code.json - Project-specific optimizations
• ✅ .claude/settings.local.json - CRITICAL FIX - Removed thousands of problematic hooks

The 1.3MB file was the smoking gun - it contained massive amounts of hook definitions that were causing Claude Code to freeze on every tool execution. This should now work smoothly!"

Yes, I had exactly the same.

My settings file got 300.000 lines of hooks, and it was crashing my laptop when running Claude.
Once I cleaned it up, all works good.

It gets duplicated randomly on specific actions, I got my file grown to 10 MB i hours using YOLO mode with playwright mcp

somehow CC wrote itself a huge and bad config file

Was this due to a bug in application logic (writes to ~/.claude/settings.json get duplicated, etc.) or just from CC yolo-ing code generation?

I didnt use the YOLO mode (never used skip permissions so far), I am not exactly sure how it happened.

I suspected it was something in the repos settings file after I was able to run Claude Code in another folder.

The detection of the error I posted in my other comment.

We found a regression in settings that causes duplicates to be saved when setting hooks through the /hooks slash command. It will be fixed in v1.0.53 or greater.

Usage has been cut in half and dumbed down. Inside info is they are using their servers to prioritize training for sonnet 4.5 to launch at the same time as xAI dedicated coding model. xAI coding logic is very close to sonnet 4 and has anthropic scrambling. xAI sucks at making designs but codes really well.

Closing this bug since v1.0.53 is out and the previous comment has nothing to do with this bug.

@Milan4747 Thanks a lot, my Claude was running super slow, i checked the files you mentioned and I found ~/.claude.json was around ~700kb i deleted it and now claude code is running with its former glory!

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