openai
How to Use GPT-6.1 Sol Ultrafast Mode in the OpenAI Responses API (2026)
Enable GPT-6.1 Sol Ultrafast mode in the Responses API with service_tier ultrafast, cut token latency for agents, and control the 6x price premium.
Enable GPT-6.1 Sol Ultrafast mode in the Responses API with service_tier ultrafast, cut token latency for agents, and control the 6x price premium.