What is SystemOne.Deciders?

A C# library built around one IDecider interface for bounded decisions: hand a model text and a fixed set of options, and get back one of those options with a probability, never free text.

Which engines sit behind the interface?

Three, per the README: TypeSafe Jev in the cloud through JevDecider, any local model in a constrained-decoding harness, and a fake for tests. Jev targets POST /v1/systemone with model jev-latest and needs TYPESAFE_API_KEY on early access.

What is the system-one-is-a-harness idea?

The README argues System One is not a special model but a harness: never let the model free-write, force it to pick from your answer space and read the distribution. Jev is one implementation; a local model plus a grammar is another, under the same contract.

What does a Decision contain?

The chosen Value, its Confidence, the full Options distribution and an Abstained flag that is set when the top probability falls under your threshold.

How does abstention work?

ChooseAsync takes an abstainBelow parameter; when the top probability comes in under that threshold the result is flagged as abstained so you can escalate to a human or a bigger model instead of acting on a weak pick.

What does the interface look like?

A public IDecider interface with one method, ChooseAsync, taking the state, the question, the option list, an optional abstainBelow threshold and a cancellation token, and returning a Task of Decision.

What is missing from the digest?

The captured excerpt cuts off inside the engines table, where the open-jev row points at daseinlabs without a full name, so install steps, target frameworks and the local harness details are not visible; no license is listed and the repo has 0 stars.

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SystemOne.Deciders

A C# library that puts TypeSafe Jev, a local model in a constrained-decoding harness and a test fake behind one IDecider interface, returning a chosen value with its confidence, the full options distribution and an abstain flag instead of free text.

See highlights Open github.com

Stars: 0
Language: C#
Reading time: 2 min
Published by: Community
Author: egarim
Last verified: Oct 2026

egarim/systemone-deciders

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One C# IDecider, three engines: TypeSafe Jev (cloud), any local model in a constrained-decoding harness, and a fake for tests. 'System One' bounded decisions in .NET.

Forks: 0
Last pushed: Updated Sep 2026

Repo stats from the GitHub API, cached Oct 2026.

Tagscommunity github csharp dotnet

Works forJev for Classification Jev for Decision gating

Used inJev for Software & DevTools

Languages: C# / .NET
Platforms: API
Capabilities: Open sourceRequires API key

Highlights

One IDecider interface over TypeSafe Jev (cloud), any local model in a constrained-decoding harness, and a test fake.
Decision carries the chosen Value, its Confidence, the full Options distribution and an Abstained flag.
abstainBelow sets a threshold: if the top probability falls under it, the result flags for escalation.
Frames System One as a harness, not a model: force a pick from the answer space and read the distribution.
JevDecider targets POST /v1/systemone with model jev-latest and needs TYPESAFE_API_KEY on early access.

Watch out

README and GitHub metadata reviewed 2026-10-17; the captured excerpt cuts off inside the engines table, where the open-jev row names daseinlabs without a full link, so install steps, target frameworks and results are not visible; no license is listed.

Questions about this entry

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From the Jev guides

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