[Bug] Stack Overflow in CLI v2.1.37 - Missing turnCount increment in CZ function

Bug Report: Stack Overflow in Claude Code CLI v2.1.37

Summary

RangeError: Maximum call stack size exceeded in cli.js CZ function due to missing turnCount increment in recursive calls.

Environment

• Claude Code: v2.1.37
• Node.js: v20.19.0
• Platform: macOS Darwin 24.6.0

Root Cause

The CZ function (main query handler) has recursive calls that do not increment turnCount, causing maxTurns checks to never trigger:

1. maxOutputTokens recovery path: turnCount passed as j instead of j+1
2. Stop hook message path: turnCount not incremented

When these conditions persist (e.g., repeated API errors, stop hooks returning messages), the recursion becomes infinite.

Code Evidence (from error stack)

// Path 1: maxOutputTokens recovery - NO turnCount increment
yield*CZ({...P,...k,V1}, ..., turnCount: j, ...);  // BUG: should be j+1

// Path 2: Stop hook messages - NO turnCount increment
yield*CZ({...P,...k,...W}, ..., stopHookActive: true, ...);  // BUG: missing turnCount

// Path 4: Main loop - CORRECT increment
yield*CZ({...P,...k,...y}, ..., turnCount: j1, ...);  // OK: j1 = j + 1

Reproduction Conditions

• Long conversation history (triggers compact)
• Multiple background agents running
• Stop hooks returning messages
• API errors requiring recovery

Suggested Fix

Ensure all recursive calls to CZ increment turnCount or have alternative termination conditions:

// Fix for path 1
yield*CZ({...P,...k,V1}, ..., turnCount: j + 1, maxOutputTokensRecoveryCount: X + 1, ...);

// Fix for path 2
yield*CZ({...P,...k,...W}, ..., stopHookActive: true, turnCount: j + 1, ...);

Impact

• Users with long conversations or multiple agents hit this frequently
• Workaround: restart CLI, /compact, or increase Node stack size

Attachments

• Full error stack trace available
• User context: nora-80b-runpod project, 30+ min conversation, multiple agents