Agent Optimizer, Agent Plugins 1.0 & Sonnet 4.6 Sunset

Microsoft Developer shares a quick news update covering Agent Optimizer in Microsoft Foundry, the GA release of Agent Plugins 1.0 across multiple Copilot surfaces, and a timeline note that Claude Sonnet 4.6 will leave most GitHub Copilot experiences on September 1.

Overview

Agent Optimizer in Microsoft Foundry

• Agent Optimizer in Microsoft Foundry automatically improves:
  • Agent instructions
  • Skills
  • Tool descriptions
• These improvements are derived from evaluation results.
• No model changes are required.

Agent Plugins 1.0 reaches GA

• Agent Plugins 1.0 is generally available across:
  • VS Code
  • Copilot CLI
  • The Copilot SDK
  • The Copilot app
• The plugin packaging approach is described as:
  • A skill plus an MCP server bundled into a single plugin
  • “Build-once, run-everywhere”
• The ecosystem/backing mentioned includes:
  • AWS
  • Anthropic
  • Microsoft
  • OpenAI
  • Vercel
  • Google

Claude Sonnet 4.6 sunset in GitHub Copilot

• Claude Sonnet 4.6 is stated to leave most GitHub Copilot experiences on September 1.

Links

• https://aka.ms/devblogs.microsoft.com/ai
• https://aka.ms/devblogs_visual_studio_update
• https://aka.ms/devblogs_foundry_update