
OpenAI released the Decisions API in beta on 6 October 2026[1]. Given text or images, it returns typed answers: the probability that a condition is true, one option from a fixed set, or a score against a rubric[2].
According to OpenAI, it answers about 10 times faster than the Responses API[1,2]. gpt-6-luna is currently the only model, and the endpoint is POST /v1/decisions[2]. OpenAI expects general availability in the coming weeks[2].
Only input tokens are billed, at $0.10 per million[2]. There are no charges for output, cache reads or cache writes[2]. Used normally, gpt-6-luna costs $0.50 per million output tokens[1].
Regional processing premiums and long-context input multipliers still apply to this API[2]. Zero Data Retention and HIPAA use are supported for eligible customers[2].
There are three question types[2]. predicate returns the probability from 0 to 1 that a condition is true, choice returns one of the supplied options, and score returns the probability-weighted average of the indices of ordered levels[2].
choice and score also return the probability of each option and a confidence value[2]. Independent questions can be combined in one request[2]. When a question depends on an earlier answer, send separate requests[2].
For extracting data into your own JSON schema or generating an explanation, OpenAI points to Structured Outputs in the Responses API[2].
On 15 October, GPT-Live gained the ability to call Decisions directly[1]. An application can act on what a user says while the user is still speaking[1].