September brought two new models to GitHub Copilot, Claude Sonnet 5.5 and GPT-6.1 Sol. It also added HydraFusion, a multi-model orchestration system, as a research preview.
Models and providers
- GPT-6.1 Sol: OpenAI's latest model is generally available for Pro+, Max, Business and Enterprise users (released 29 September). It is strong at agentic and multistep coding and uses fewer tokens than earlier GPT-6 and GPT-5.6 models. It works in the model picker across editors, Copilot CLI and github.com.
- Claude Sonnet 5.5: Available on all paid plans and platforms (released 28 September). It matches Sonnet 5's coding performance with fewer tokens and tool calls, so tasks finish faster. Admins control access through model policies, and rollout is gradual.
Agents and automation
- HydraFusion: A research preview in VS Code and the GitHub Copilot app for Pro, Pro+, Business and Enterprise users. It picks between a single model, cascading models with quality gates, or critique-based revision, and shows each workflow step with live progress and clearer status indicators.