GPT-5.6 kernel of truth: Sol can cut its own costs, says OpenAI

The New Stack · 2 months ago · 30 ● 14 sources

OpenAI detailed how its GPT-5.6 model family balances capability and cost, with the flagship Sol model outperforming Anthropic's Claude Fable 5 on a coding benchmark while using 54% fewer output tokens. The efficiency gains come from four layers of optimization: autonomous kernel rewrites that reduced serving costs by 20%, speculative decoding that improved token generation by over 15%, incremental tokenization via WebSockets that speeds up tool-heavy workflows by up to 40%, and an append-only agentic harness that reduces context bloat. These compounding improvements position efficiency alongside raw intelligence as a key axis of competition between frontier AI labs.