GitHub Weekly: GPT-5.4, Agentic Code Review, and the Platform's AI Evolution

This week, GitHub shipped its most aggressive set of AI and platform updates yet. We're not talking incremental improvements—we're talking GPT-5.4 in production, code review running on agentic tool-calling architecture, and Copilot Memory enabled by default. If you've been waiting to see where GitHub's headed with AI-assisted development, this week gave you the answer: all-in on agents. GPT-5.4 Goes Live in GitHub Copilot GPT-5.4 is now generally available across GitHub Copilot. OpenAI's latest agentic coding model is rolling out to Pro, Pro+, Business, and Enterprise users with access in the Copilot Coding Agent, GitHub CLI, GitHub Mobile, and major IDEs (Eclipse, Xcode, JetBrains, Visual Studio). GitHub's internal testing shows GPT-5.4 hitting "new rates of success" on real-world agentic workflows. The model shows improved logical reasoning and better task execution for multi-step, tool-dependent processes—exactly what you need when agents are editing code, running tests, and iterati