[BUG] Temporary files grow to 800GB+ during normal usage

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

I asked for learning materials, Claude gave me a storage bill...

While using Claude Desktop, temporary files rapidly accumulated to over 800GB,
consuming nearly all available disk space.

Steps to Reproduce

1. Provided a ~50-line instruction prompt asking Claude to generate learning materials
2. No parallel sessions or unusual usage patterns
3. Temporary files grew to 800GB+ in a short period

Expected Behavior

Temporary files should be cleaned up or managed within reasonable disk space limits.

Actual Behavior

Temp files accumulated to 800GB+, which was discovered when macOS "System Data"
appeared abnormally large. The files were located under:

• ~/Library/Application Support/Claude/

(Already cleaned up — current size is ~57MB after manual deletion)

Environment

• OS: macOS 26.2 (Build 25C56)
• Claude Desktop: v1.1.2998
• Disk: 926GB APFS

What Should Happen?

While using Claude Desktop, temporary files rapidly accumulated to over 800GB,
consuming nearly all available disk space.

Error Messages/Logs

No error messages were displayed. The only symptom was macOS reporting
abnormally high "System Data" usage (~800GB). The issue was discovered
by manually inspecting disk usage, not through any in-app error.

Steps to Reproduce

1. Open Claude Desktop (v1.1.2998) on macOS
2. Start a new conversation
3. Send a single prompt (~50 lines) asking Claude to generate learning materials

• No parallel conversations running
• No special tools or MCP servers enabled
• Just a normal text prompt with instructions

1. While Claude is responding, disk usage spikes rapidly
2. macOS "System Data" grows to 800GB+

• Temp files accumulated under ~/Library/Application Support/Claude/

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.1.2998

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

<img width="263" height="97" alt="Image" src="https://github.com/user-attachments/assets/78696fb5-7b8e-426c-b4ff-ea8fbb0a53f5" />