Summary
The release adds GPT-6 Sol, GPT-6 Luna and Claude Opus 5.5 to the model picker when available, and reads Claude Code rule files as custom instructions. It also improves MCP OAuth scope handling, tolerates invalid neighbouring MCP entries, follows repository pull-request templates, and strengthens sandbox and session behaviour.
Why it matters
The CLI is becoming a common control surface for multiple coding-agent models, so its instruction, MCP and review-process compatibility has broad workflow consequences.
Related coverage
- Claude Code 2.1.284 makes Sonnet 5.5 the default and hardens MCP recovery
- GitHub makes Claude Sonnet 5.5 generally available across Copilot
- Firebase CLI 15.32.0 introduces function kits and deployment fixes