The Frontier Model Arrives

OpenAI's GPT-5.5 is now generally available in Microsoft Foundry , and this isn't just another incremental model release. GPT-5.5 represents a clear evolution from "smart chatbot" to "production agent"—built specifically for sustained, multi-step professional work where the cost of imprecision is high.

The improvements matter for anyone building agentic systems. Better computer-use accuracy means fewer hallucinated UI actions. Deeper long-context reasoning means agents can hold architectural intent across large codebases. Token efficiency means lower costs at scale. GPT-5.5 Pro extends this further for the most complex enterprise workflows, though at a premium: $30/M input tokens and $180/M output tokens versus GPT-5.5's $5 and $30 respectively.

But here's what actually matters: Microsoft Foundry is positioning itself as the operating system for agents at scale .…