[BUG] Memory leak: API clients created repeatedly instead of reused (8-9 GB memory 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:

Claude Code is consuming excessive memory (8-9 GB) due to what appears to be an API client leak. Debug logs show 114 API clients being created in a short session, with bursts of 24-28 clients created per second.

Environment:

• Claude Code version: 2.1.27
• OS: macOS Darwin 24.3.0
• Installation: Homebrew cask (/opt/homebrew/Caskroom/claude-code/2.1.27/claude)

Symptoms:

• Single claude process using 8-9 GB RAM (25% of system memory)
• Memory grows quickly even with minimal conversation

What Should Happen?

Expected behavior:

• no OOM events
• API clients should be reused rather than recreated, and memory usage should stay reasonable (< 1 GB for typical sessions).

Error Messages/Logs

Evidence from debug logs:

  # 114 total API clients created
  $ grep -c "Creating client" ~/.claude/debug/latest
  114

  # Bursts of client creation (clients created per second):
    28 12:53:52
    24 12:55:27
    24 12:54:38
    24 12:54:28

  Example of 17 clients created in the same millisecond:
  2026-01-31T12:55:27.714Z [DEBUG] [API:request] Creating client...
  2026-01-31T12:55:27.714Z [DEBUG] [API:request] Creating client...
  (repeated 17 times)

Steps to Reproduce

Steps to reproduce:

1. Start Claude Code
2. Have a brief conversation
3. Monitor memory with Activity Monitor or ps aux
4. Check ~/.claude/debug/latest for client creation count

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.27

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_