OpenAI Makes Decisions API Widely Available, Cutting Latency to Sub-Second Levels
OpenAI has opened its Decisions API to all customers, optimizing ChatGPT Luna to reduce inference latency from seconds to milliseconds, challenging TypeSafe's Jev models.
OpenAI officially made its Decisions API available to all customers this Thursday (October 22, 2026). The service is based on a reconfigured ChatGPT Luna model designed to provide fast, low-cost intelligent decision-making capabilities, directly entering the "System One" decision model market pioneered by TypeSafe's Jev models.
Nikunj Handa, OpenAI's product lead for APIs, stated that after seeing Jev models, his team recognized numerous use cases. Instead of building a specifically calibrated decision model, they optimized Luna for faster inference and lower costs. Handa noted that this adjustment reduced response times from one to three seconds down to 100–180 milliseconds. While future training may further improve these metrics, current Luna configurations suffice for now.
In initial trials, customers such as Box, Datadog, Ramp, and Speak used the API to replace existing LLM workflows for higher throughput. Andrew Hsu, CTO at Speak, reported that the Decisions API allowed the company to cut the time between actions from 1.4 seconds to 0.13 seconds. OpenAI itself also utilized the product to enhance the responsiveness of its Dots voice assistant.
However, public benchmarks indicate OpenAI is not leading in this specific domain. On the AIM System One Index and the Artificial Analysis Decision Index, Liquid's D1 Ultra and Base Lab's Elephant-1 perform better, while OpenAI's Decision Model ranks eighth and fourteenth respectively. TypeSafe's Jev models remain competitive and are the most widely queried on OpenRouter. Furthermore, there is no universal standard for what constitutes a good decision model, as trade-offs between intelligence, cost, calibration, and speed vary significantly across different workloads.