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Welcome to SystemOne.dev

Most AI content assumes you want a model that talks. This site assumes you want a model that decides, and then gets out of your way.

What a System One model is

Section titled “What a System One model is”

A model that answers typed questions about your program’s state, without generating text:

You ask You get back
a noul (yes/no): “Is this email phishing?” noul: the probability of yes
a choice: “Which team should handle this ticket?” + options the chosen option and a probability for every option
a score: “How urgent is it?” + ordered levels a probability for every level, and their weighted average

Every question in a request is answered in one pass. The answer is always one of the options you gave, so there’s nothing to parse and nothing to retry. The name comes from the psychology of fast, intuitive judgement (System 1) versus slow, deliberate reasoning (System 2). Most good AI systems need both, and this site is about the first.

The one idea

Section titled “The one idea”

A generative model answers “what should I say?”. A decision model answers “which of these, and how sure am I?”. That second answer is typed, so you can branch on it, test it and monitor it:

from systemone import Client, Choice


client = Client("http://localhost:8093")
r = client.system_one(
    state=application,                       # your real JSON, not a prompt
    questions={"decision": Choice("Should this application be approved?",
                                  {"approve": None, "review": None, "reject": None})},
)
d = r.choices["decision"]
if d.choice != "review" and d.probabilities[d.choice] >= 0.95:
    apply_automatically(d.choice)
else:
    send_to_reviewer(application, d.probabilities)

What’s here

Section titled “What’s here”
Section What it gives you
Concepts The mental model, mostly unlearning what generative AI taught you
Cookbook Patterns to paste into a real codebase
Projects End-to-end builds, with benchmarks
Blog Field notes, results and community write-ups

What this site is not

Section titled “What this site is not”
  • Not a product brochure. It’s run by the maintainers of the open-source SystemOne Builder and the Kenning models. The patterns apply to every engine that speaks the format, including hosted ones: see Engines. We publish our benchmarks, including where Kenning loses.
  • Not anti-LLM. Generative models are extraordinary at what they’re for. The argument here is about routing: send the decisions to a fast model, and the writing and reasoning to a slow one.

Next

Section titled “Next”