OpenAI makes the Decisions API generally available, built on GPT 6 Luna, with up to 400 questions per request and input only pricing of $0.10 per million tokens
The Decisions API is now generally available! To celebrate, I had Codex reimagine a very important app… 🌭
Context
It targets the many small classification and routing calls inside agents. OpenAI says answers arrive up to 10x faster than the Responses API, a company figure supported by customer quotes OpenAI chose to publish.
The lead post is from Romain Huet, who describes himself as head of developer experience at OpenAI, so it is an announcement from a company employee. OpenAI's own page, dated October 22, says the Decisions API is generally available with GPT 6 Luna through a dedicated endpoint. The API returns a probability, a choice or a score for questions a developer defines. OpenAI's page says input costs $0.10 per million tokens and there are no output token charges.
Deep dive
Romain Huet posted at 4:37 PM Eastern on October 22 that the Decisions API is generally available, and that to celebrate he had Codex reimagine a very important app, with a hot dog emoji. The post does not name the app, and the attached two minute video is not described in the text.
OpenAI's announcement says applications and agents make many small decisions, such as classifying an input or routing a request, and that latency and cost add up at scale. It says the API focuses GPT 6 Luna on questions with bounded answers and works on text, images and structured inputs up to 10x faster than GPT 6 Luna through the Responses API. That speed figure is OpenAI's own.
Since the public beta, OpenAI says it added a native GPT Live integration, prompt caching, inference residency in the US and EU, native JSON inputs, images in question instructions, and a limit of 400 questions per request, twice the previous limit. The three answer types are predicate, choice and score.
OpenAI's page quotes customers. Box reports about 5x faster route selection on 30 certificate of insurance cases, Datadog reports 40x faster p95 latency than available frontier models with comparable accuracy, Ramp reports 4x faster and 30% cheaper than GPT 6 Luna, and Sierra reports under 280 ms p95, and Speak reports a drop from 1.4 s to 0.13 s in time to next action with GPT Live. These are customer statements published by OpenAI, not independent measurements. OpenAI lists input at $0.10 per million tokens and cached input at $0.01.
What to expect next
OpenAI's page says the API is available with GPT 6 Luna through the dedicated Decisions endpoint, and lists no other model. Independent measurements of the speed and cost claims were not found in the sources reviewed, and the customer figures come from OpenAI's own page. OpenAI says it continues to work on latency, including added capacity in several regions in Asia. Details on caching for 30 minute and 12 hour writes are in OpenAI's pricing guide. Whether more models are added to the endpoint is not stated.