GitHub Copilot: Claude 3.5, Gemini 1.5 Flash Added

GitHub is expanding the AI models available in Copilot. Subscribers on Pro+, Max, and Business tiers, along with Enterprise customers, can now access Claude Fable 5.1. Gemini 3.8 Flash is also rolling out to these tiers, plus Copilot Pro users. These updates bring new features to the coding assistant. The Copilot app and command-line interface now respect content exclusions. Also, the Copilot harness is generally available in Copilot for JetBrains. For VS Code 1.136, Agent Merge is in public preview, and chat backgrounds are experimental. Chat sessions have been reorganized to group related conversations. This follows the recent general availability of GPT-6 Astra in Copilot, designed for long-horizon autonomous coding. These developments are part of Microsoft's larger push into AI-assisted development, aiming to boost productivity.