Microsoft replaces Anthropic's Claude with OpenAI GPT-5.6 for engineers
Microsoft just swapped out Anthropic's Claude for OpenAI's GPT-5.6 as its main AI model for engineers, according to 404 Media.
The change, shared in an internal memo, comes after Microsoft spent May telling its Windows, Office and Surface engineers to wind down Claude Code and move to GitHub Copilot CLI before the fiscal year closed on June 30.
Jay Parikh, Microsoft's CoreAI EVP, explained they want "more impact per token," not just lower usage.
Copilot automatically routed code to Claude
This move is all about boosting efficiency.
Previously, most coding tasks were automatically sent to Claude by Copilot, even if engineers didn't pick it, which racked up high token usage and expenses.
Now, with GPT-5.6 as the default, that auto-routing stops and workloads get streamlined.
Microsoft sets division AI token budgets
Microsoft also set AI token budget targets for each division, and employees can look up their individual spend on an internal dashboard.
While you'll still find Claude in some tools like Copilot CLI and Microsoft 365 Copilot, it won't be the go-to option anymore, part of a bigger push to make AI resources work smarter across the company.