GPT-5.5 is OpenAI’s most capable agentic AI model yet–at twice the API price

OpenAI launched GPT-5.5 on April 23 as what it calls “a new class of intelligence for real work and powering agents,” and the framing is deliberate.

OpenAI says it’s the most capable agentic AI model to date, built from the ground up to plan, use tools, check its own output, and work through task...