• Copilot Chat Extension Version: 0.29.1
• VS Code Version: 1.102.2
• OS Version: Darwin arm64 24.5.0 (macOS 15.5)
• Macbook Pro M3 (16Gb ram)
• Feature (e.g. agent/edit/ask mode): Agent
• Selected model (e.g. GPT 4.1, Claude 3.7 Sonnet): GPT-4.1, GPT-4o
• Logs:

vscode-app-1753371068157.log

Steps to Reproduce:

1. Work with a large monolithic python file, ~4k lines of code.
2. GPT-4.1/GPT-4o in Agent mode will crash the extension host (Code Helper (Plugin)?) and reset all changes when attempting to apply edits.
3. Attempted on an iMac 2019 with 24Gb of ram, same crash result.
4. Premium models do not crash.

Screenshot just as crash happened, Code Helper (Plugin) approached 4Gb of ram