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SystemOneDotNet

.NET client for TypeSafe System One: typed Choice, Score and Noul questions in, answers with probabilities and confidence out.

LibrarybetaMIT
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Overview

SystemOneDotNet is a .NET client for TypeSafe System One models such as Jev. Developers declare the answer space in C# and get C# values back: ChoiceAnswer with the chosen option, per-option probabilities and confidence; ScoreAnswer with a probability-weighted score and legend; and NoulAnswer with the probability of yes. One request can carry several questions, evaluated in parallel against the same state. The default model alias is jev-latest.

The package targets .NET Standard 2.0, so it runs on .NET Framework 4.6.2 and later as well as modern .NET, and depends only on System.Text.Json. It suits .NET teams doing triage, routing, moderation or lead scoring who want to replace regex or prompt-and-parse code. The README encourages turning confidence into policy, for example acting automatically above a threshold and escalating otherwise, and notes there is no automatic boolean conversion for Noul answers.

What the decision model decides

TypeQuestionAnswers
ChoiceWhich team should handle this?billing · technical · sales
ScoreHow frustrated is the customer?Calm · Frustrated · Very angry
Yes / noDoes this message convey urgency?—

How it works

  1. Install the NuGet package and set an API key.
  2. Call ChoiceAsync, ScoreAsync or NoulAsync, or batch several questions.
  3. Receive typed answers with probabilities and confidence.
  4. Act automatically above a confidence threshold, escalate below it.

Strengths

  • Wide .NET compatibility with a single dependency.
  • Typed answers remove output parsing.
  • Several questions in one request with little extra latency.

Caveats

  • Requires a TypeSafe API key and hosted service.
  • Thresholds must be chosen by the application.

Getting started

dotnet add package SystemOneDotNet

At a glance

Type
Library
Status
beta
Language
C#
Runtime
.NET Standard 2.0
Has code
yes
License
MIT

Use cases and integrations

How curated lists describe it

  • .NET client for TypeSafe System One (Jev) — typed questions in, typed answers with probabilities and confidence out. No prompt engineering, no output parsing.

    hellogumbo/awesome-jev

Frequently asked questions

Which .NET versions are supported?

Anything compatible with .NET Standard 2.0, including .NET Framework 4.6.2+ and .NET Core 2.0+.

Does it need a TypeSafe key?

Yes, it calls TypeSafe's hosted System One API.

How should I use confidence?

The README suggests acting automatically when confidence is high and escalating below a threshold you choose.

Related projects

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    Local service to define, test and publish versioned Jev judgment functions, callable over HTTP by backends and over MCP by agents.

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    Ruby gem that stores Jev Noul, Choice and Score answers about a record's text as ordinary ActiveRecord columns you can query.

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  • systemone

    Unofficial Go client for TypeSafe System One with generics that bind each choice, score and noul answer to a declared Go type.

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  • jevlang

    Python dialect that adds a '~' operator and jev/case blocks so a branch can ask Jev a yes/no, scale or choice question.

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  • DecisionKit

    Provider-independent .NET decision engine with a separate TypeSafe Jev provider package mapping Choice, Score and Noul to /v1/systemone.

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  • jev (Elixir)

    Elixir/OTP library treating Jev as a peer process whose answers arrive as messages you pattern match in GenServer clauses.

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