According to Greg Brockman on X, OpenAI's GPT-5.5 and GPT-5.5 Pro are now available on OpenRouter, with GPT-5.5 achieving state-of-the-art performance for long-running work across code, data, and tools, and GPT-5.5 Pro positioned for more complex reasoning and analysis. As reported by OpenRouter on X, developers can route requests to these models immediately, enabling sustained multi-step workflows and tool-augmented tasks through the OpenRouter API. According to the OpenRouter announcement, this availability creates business opportunities for AI app builders to reduce task interruptions and improve throughput in agents, data pipelines, and software development lifecycles that require extended context and durable execution.