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Modelsystem

The public contribution surface for modelsystem.one, a curated catalog of System One decision models: systems returning typed choice, score or boolean answers with calibrated probabilities instead of chat text. The site code is private.

Stars
1
License
MIT
Published by
Community
Author
fabricioctelles
Last verified
Oct 2026

About this project

modelsystem.one is a curated catalog of System One / Decision Models — AI systems that return typed decisions (choice, score, boolean) with calibrated probabilities, instead of free-form chat text. This repository is the public contribution surface for the project (issues, PRs, discussions). The website application source lives in a separate private repository. Inspired by Kahneman’s Thinking, Fast and Slow:

Quoted from the project's README. Read the full README.

Highlights

  • Inclusion criteria are three lines: a primary interface returning typed decisions, public availability as GA, beta or waitlist, and minimum API documentation.
  • The repository holds contributions and project meta only; the application source is in a separate private repository, so PRs against app code land nowhere.
  • A comparison table frames the split: free text and seconds for generation and reasoning, typed decisions and milliseconds for routing and guardrails.
  • A quadrant page places models on maturity against capability, alongside a spec page, integration guides, category news with RSS and a Portuguese mirror.

Watch out

This is not software you run. It is a catalog plus the place to argue about it, and the README is explicit that pull requests expecting the application source will find nothing here. Inclusion is editorial, gated on a published spec rather than open by default, and the only entrant the README names is Jev, described as leading the public category today. There is also nothing to check the claims against: no comparison methodology, no per-model test data, and the framing is the site's own argument about what counts as a decision model. Licensing is split — MIT over this repository's own content, while site content and third-party trademarks such as TypeSafe's stay with their owners, and the catalog states it is not affiliated with those vendors. Copy reviewed against the repository README on 2026-10-04, not from running it.

Questions about this entry

Short answers drawn from the linked project or page.

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