OpenAI previews GPT-5.6 Sol, leading with agents, code, biology and cyber

OpenAI has previewed GPT-5.6 Sol, the top model in a new GPT-5.6 family that also includes Terra, described as a balanced everyday model, and Luna, a faster and cheaper variant. OpenAI says Sol is its strongest model to date, with its primary focus on complex agentic tasks, coding, biology and cybersecurity.

The release method is unusual. According to AI Post, OpenAI is releasing Sol to trusted partners first and granting broader access later, with what the channel describes as U.S. government coordination at the outset. That sequencing, one capability tier at a time rather than a single public launch, resembles the access controls that labs now apply to models that could meaningfully aid work in biology and offensive cyber operations.

The capability claims are, for now, OpenAI's own. The company emphasizes agentic and coding performance, the dimensions where buyers most directly notice a model upgrade. But the preview post is a vendor publication rather than an independent reproduction, and no third-party evaluation results were available at the time of writing. Russian-language coverage from AI ML Big Data repeats the emphasis on agentic, coding, biology and cybersecurity work and notes the three-tier structure without adding outside benchmarks.

On serving speed, AI Post separately reports that Sol is targeted to deliver roughly 750 tokens per second. The channel compares that with current GPT-5.5 priority and scale tiers, which sustain more than 50 tokens per second for 99 percent of requests, and it attributes the higher throughput to a deployment on Cerebras hardware. That figure, like the capability claims, is a vendor or third-party assertion rather than a measured public benchmark.