Build your own decision model

By Nish Tahir — 10 Oct 2026

"System one" decision models are models that infer and respond with calibrated probabilities or every allowed answer.

Consider your everyday language model, to get typed output from it (JSON), you may use Structured Output to constrain the output to guaranteed valid JSON. While model prefills the input in one pass, it still has to go perform a pass for every token in order to generate a valid response.

In this example, 11 passes are required to generate the final output. (We're not accounting for speculative decoding and other inference optimization techniques.)

prompt (prefill) generated (predicted) being predicted