[BUG] Error: Bad substitution: [function name]

Environment

• Platform (select one):
• [ ] Anthropic API
• [ ] AWS Bedrock
• [ ] Google Vertex AI
• [ ] Other: <!-- specify -->
• Claude CLI version: 1.0.41 (Claude Code)
• Operating System: macOS 15.5 (24F74)
• Terminal: Ghostty 1.1.3

Bug Description

Claude consistently throws an error because it tries to create a script in /tmp which it does not have access to.

Steps to Reproduce

1. Ask it to debug an issue that requires writing a script

Expected Behavior

Claude creates the script in the local directory which it has access to.

Actual Behavior

Claude tried to create the script in /tmp and crashed, with the bad substitution error.

Additional Context

You can work around this by explicitly asking Claude to create debug scripts in the local directory.

Trace:

Error: Bad substitution: [function name]
    at H (file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:7:2204)
    at file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:7:2863
    at Array.map (<anonymous>)
    at vi2 (file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:7:1942)
    at Object.A (file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:7:3027)
    at i1A (file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1512:3494)
    at iy (file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1518:77)
    at Object.isReadOnly (file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1590:3316)
    at Object.isConcurrencySafe (file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1590:3232)
    at file:///Users/blockshane/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1931:7014

Node.js v22.16.0