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TypeSafeJevPlayground

Unofficial dependency-free .NET port of the TypeSafe JS SDK v0.6.0, accompanying blog posts including an MCP server.

Libraryprototype
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Overview

TypeSafeJevPlayground is an unofficial .NET port of the official JavaScript SDK v0.6.0, targeting net11.0 and C# 15 with System.Text.Json and no runtime package dependencies. The author describes it as vibe-coded and to be used at your own risk. It accompanies two blog posts: one introducing a community .NET SDK and one on building a Jev MCP server with .NET.

The API mirrors the JavaScript systemOne call through SystemOneRequest. State, instructions and criteria accept JSON strings, objects, arrays or null; it validates non-empty question dictionaries and criteria, requires at least two score levels, forwards extra top-level fields and supports cancellation. It also lists models. It validates that questions and criteria are not empty and that score criteria have at least two ordered entries, and supports cancellation tokens and model listing.

What the decision model decides

TypeQuestionAnswers
Yes / noAssess safety.The statement is safe. · The statement is unsafe.
ChoiceChoose a topic.science · other
ScoreRate quality.poor · good · excellent

How it works

  1. Create TypeSafeClient with an API key.
  2. Build a SystemOneRequest.
  3. Call SystemOneAsync.
  4. Cast and read answers.

Strengths

  • No runtime dependencies.
  • Accompanied by explanatory blog posts.

Caveats

  • Described by the author as vibe-coded; use at your own risk.
  • Targets net11.0, which may be ahead of many projects.

At a glance

Type
Library
Status
prototype
Language
C#
Runtime
.NET library
Has code
yes

Use cases and integrations

How curated lists describe it

Frequently asked questions

Is it production-ready?

The author calls it an unofficial, vibe-coded port to use at your own risk.

What does it port?

The official JavaScript SDK v0.6.0.

Is there an MCP example?

Yes, in the accompanying blog post on building a Jev MCP server with .NET.

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