VS Code 1.143 makes the Copilot SDK-based harness the default, adds multi-model comparison and on-device MAI Code 1.1 Flash
Microsoft shipped Visual Studio Code 1.143. The Copilot harness, built on the Copilot SDK, is now the default for new sessions and works across the editor and Agents window. A Compare Models preview runs several models on one task with an optional Judge model, an experimental mode runs MAI Code 1.1 Flash on a local NVIDIA GPU, and large chats open much faster.
Key Takeaways
- Default harness: new sessions use the Copilot harness built on the Copilot SDK, which can run in the background and move between the editor and the Agents window
- Compare Models (Preview): one prompt runs 2 or more models in parallel, mixing Copilot, Claude and Codex harnesses, with an optional Judge model scoring time and token use and a Synthesize step
- On-device models (Experimental): download MAI Code 1.1 Flash to run locally, labeled On-device with no AI credits used; needs an NVIDIA GPU with 96 GB+ memory
- Performance (vendor figures): cold-opening a ~1,150-request chat dropped from 35.6 s to 9.0 s, and window freeze time from 28.3 s to 0.6 s
- Also: the editor diagnostic highlight limit rises from 500 to 5,000 per file, and the Windows installer can install GitHub Copilot CLI
Linked Models & Agents: