Memory leak: ArrayBuffers grow ~1.4 GB/min while idle, reaching 28.8 GB

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 consumes massive memory while completely idle (no prompt submitted). Memory climbed from 2.3 GB to 28.8 GB
within minutes of launching, with no user input being processed.

The /heapdump diagnostics confirm the issue is ArrayBuffer accumulation:

• ArrayBuffers: 15.5 GB (out of 16 GB total heap)
• V8 heap: only 57 MB — the leak is entirely in binary buffers, not JS objects
• Growth rate: ~83,711 MB/hour (~1.4 GB/min)
• Uptime at capture: 241 seconds (~4 minutes)

The actual V8 heap is healthy at 57 MB. Something is allocating ArrayBuffers (likely related to network/streaming/API
connections) and never freeing them, even when the session is idle.

Environment:

• Claude Code v2.1.72
• Node v24.3.0
• macOS Darwin 25.2.0
• 32 GB RAM machine

What Should Happen?

It should not constantly climb.

Error Messages/Logs

Steps to Reproduce

Reproduction:

1. Launch claude
2. Do nothing — don't submit a prompt
3. Watch status bar memory climb continuously

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.1.72

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

e571c74d-b1d6-4db5-8421-187a476cf1d2-diagnostics.json