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All Jev resources

This is the full index of everything Jev: 2231 entries for TypeSafe AI's flagship System One model, from official documentation, SDKs, and cookbooks to community-built clients, MCP servers, agent tools, and write-ups. Every entry is tagged by category, format, and topic, and sorted newest first.

Filter by category or tag, or search titles, descriptions, authors, and repos. Open any card for its detail page — most entries carry a verified deep dive with highlights, caveats, and a quickstart snippet.

Entries
2231
Categories
11
Official
93
Community
2138
Source sites
148
Deep dives
2231

Last updated . Entries are added as they appear and re-checked when they are touched.

Browse Jev by category

11 ways into the ecosystem. Each category page leads with its own shortlist of starting points.

All 2231 Jev resources

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Showing 241–288 of 736 resources

4GitHub stars
JVM SDK for the TypeSafe System One API with a pure-Java core, Kotlin DSL, Spring Boot starter, and Spring AI bridge, speaking the System One wire contract across hosted and self-hosted backends.
Jev Repos & SDKs#community#awesomejev#catalog-import
4GitHub stars
Self-hosted trading intelligence platform pairing a Python scoring and risk engine with a Claude plus Jev analyst, where the analyst answers only through fetched data tools and the user confirms every action at their broker.
Jev Tools & CLIs#community#awesomejev#catalog-import
9GitHub stars
Cookbook of runnable Jev examples, reusable composition patterns, and theory notes showing how to put a fast typed classifier in front of slower LLM fallbacks.
Jev Agents & MCP#community#awesomejev#catalog-import
11GitHub stars
NPM package and Ink TUI for asking Jev small typed questions stored as jevel files, mapping confidence to act, mark, or fall_back decisions with every decision kept in a local log.
Jev Agents & MCP#community#awesomejev#catalog-import
10GitHub stars
Claude Code plugin that re-checks each reply and file edit against CLAUDE.md or AGENTS.md rules with one batched Jev request, quoting broken rules back so the model fixes them in the same turn.
Jev Agents & MCP#community#awesomejev#catalog-import
6GitHub stars
Provider-neutral benchmark and harness for typed System One decisions, freezing corpora, manifests, and scoring so engines are compared on identical rows across accuracy, calibration, and robustness axes.
Jev Practices & Patterns#community#awesomejev#catalog-import
4GitHub stars
Context manager where Jev scores tool output into keep, pointer, or quarantine classes while kept lines stay verbatim and anything moved out can be expanded back byte for byte.
Jev Demos & Experiments#community#awesomejev#catalog-import
26GitHub stars
Explainable day-trip planner where an LLM drafts the itinerary, Jev screens candidates and reviews choices with typed decisions, and deterministic controller code owns routes, timing, validation, and repair.
Jev Demos & Experiments#community#awesomejev#catalog-import
4GitHub stars
Research decoder that treats Jev as if it were a language model, assembling replies in code from Choice distributions over a hierarchical codebook instead of generated tokens.
Jev Practices & Patterns#community#jevbest#catalog-import
Recruiter dashboard that applies calendar date math plus visa, tenure, license and clearance gates, then a Jev decision step, sorting resumes into disqualified, advance or manual review.
Jev Tools & CLIs#community#jevbest#catalog-import
9GitHub stars
Hermes Agent plugin exposing Jev as four coding-workflow tools for parallel judgments, binary checks, option routing and rubric scoring, with a bundled question-design skill.
Jev Agents & MCP#community#jevbest#catalog-import
27GitHub stars
Local typed-decision models that answer Choice, Noul and Score in one forward pass on your own machine, with a Python API, local HTTP server and System One request shape.
Jev Demos & Experiments#community#jevbest#catalog-import
LangChain deepagents middleware that replaces SkillsMiddleware with per-turn judging, loading only the SKILL.md files a turn needs so large catalogs stay out of the prompt.
Jev Agents & MCP#community#jevbest#catalog-import
3GitHub stars
Stdlib-only Python CLI and agent skill that evaluates a state against typed Choice, Score and Noul questions over the System One API without generating prose.
Jev Agents & MCP#community#jevbest#catalog-import
4GitHub stars
Community Swift SDK for TypeSafe with a dependency-free client that sends state plus typed questions and returns inferred answers for Apple platforms.
Jev Repos & SDKs#community#jevbest#catalog-import
3GitHub stars
Experiment where Jev controls the tool loop and a LangChain chat model only fills argument values and final prose, using 12 local read-only MCP tools across documents, math, and calendar.
Jev Agents & MCP#community#jevbest#catalog-import
4GitHub stars
Community Go client for the TypeSafe System One evaluation API with raw structs and a builder that produce the same EvaluationRequest, defaulting to jev-latest.
Jev Repos & SDKs#community#jevbest#catalog-import
3GitHub stars
Browser agent where Jev makes every navigation decision and agent-browser performs clicks and typing, stopping when the named goal page is reached or blocked.
Jev Demos & Experiments#community#jevbest#catalog-import
3GitHub stars
TypeScript layer that binds a Standard Schema state to Jev Choice, Score, and Noul questions, validating locally before sending one parallel request with typed projections.
Jev Repos & SDKs#community#jevbest#catalog-import
Local three-panel playground for trying TypeSafe judgments, with 110 editable examples across 22 categories including A/B comparisons, running one request per Run without bulk automation.
Jev Demos & Experiments#community#jevbest#catalog-import
6GitHub stars
Idiomatic Java 17 and later client for Jev with one-off evaluate calls, reusable JevRequest builders, async support, and structured rubric helpers.
Jev Repos & SDKs#community#jevbest#catalog-import
6GitHub stars
Go driver for native macOS apps where Jev picks the next Accessibility action from live app and window state, with code mapping typed answers to tool calls.
Jev Demos & Experiments#community#jevbest#catalog-import
7GitHub stars
MCP server exposing Jev Choice, Score, Noul, batched ask, file-reading triage, and model listing as typed tools with full probability distributions.
Jev Agents & MCP#community#jevbest#catalog-import
3GitHub stars
macOS window switcher that predicts the app you want on ⌘` from recent switching history, asking Jev to pick from the 10 most recently used running apps with a 1 s fallback.
Jev Tools & CLIs#community#jevbest#catalog-import
3GitHub stars
Independent browsable field guide to Jev 1.13.0 covering 11,621 text-study requests, Snake controllers, and a 3D-city driving lab with replays, token counts, and reports.
Jev Practices & Patterns#community#jevbest#catalog-import
6GitHub stars
Agent skill plus CLI that rebuilds a plain requirement, an existing prompt, or current LLM-call code as typed Jev choice, score, and noul questions with runnable code.
Jev Agents & MCP#community#jevbest#catalog-import
4GitHub stars
Browser agent that takes a goal and start URL, reads each page as a numbered control table, and has Jev pick one operation and target per step until done or stuck.
Jev Demos & Experiments#community#awesomejev#catalog-import
4GitHub stars
Design-time toolkit for using Jev from a coding agent, combining docs, a stdio MCP server, and an agent skill for decomposing judgments into Choice, Score, and Noul.
Jev Practices & Patterns#community#awesomejev#catalog-import
5GitHub stars
Electron app for controlling a Windows 10 or 11 PC by voice in Turkish or English, routing decisions through OpenRouter typesafe/jev-1.13 with UI Automation first.
Jev Demos & Experiments#community#awesomejev#catalog-import
136GitHub stars
Unofficial operator companion showing how Jev works as a function call, with an offline lab, smart-home demo, TypeScript harness CLI, and portable agent skills.
Jev Practices & Patterns#community#awesomejev#catalog-import
3GitHub stars
Semantic test matchers for Vitest and Jest where plain-English expectations become single Noul judgments, with probabilities mapped to pass, fail, or ambiguous.
Jev Practices & Patterns#community#awesomejev#catalog-import
4GitHub stars
Hook-level gate for coding agents that watches tool use for grader tampering, hidden-test edits, and eval-process interference, steering toward checks that cannot be gamed.
Jev Practices & Patterns#community#awesomejev#catalog-import
4GitHub stars
Fills Notion database properties with calibrated Jev judgments through a native macOS SwiftUI app and a terminal CLI, polling row edits and routing uncertain entries to review.
Jev Demos & Experiments#community#awesomejev#catalog-import
3GitHub stars
Browser page that turns pasted text and a plain-language question into a runnable Jev request, then keeps every run so you can check whether the answer holds steady.
Jev Demos & Experiments#community#awesomejev#catalog-import
5GitHub stars
Unofficial Java SDK that defines Choice, Noul, and Score questions in code and submits them together for typed answers instead of parsed text.
Jev Repos & SDKs#community#awesomejev#catalog-import
3GitHub stars
Life-and-civilization sim where every voluntary action is a validated Jev Choice with ledger receipts, while optional LLM planners may only propose grounded intentions.
Jev Practices & Patterns#community#awesomejev#catalog-import
Shell gate for coding assistants that judges commands by effect and blast radius, asking Jev twelve questions or a chat model, with fast rules first.
Jev Agents & MCP#community#awesomejev#catalog-import
6GitHub stars
Community n8n node that adds a Jev judgment step to workflows, returning one of your options with probabilities so unsure items can go to review.
Jev Integrations & Adapters#community#awesomejev#catalog-import
5GitHub stars
Experimental OpenTelemetry Collector processor that asks Jev about metric metadata and applies explicit keep or drop policy, starting in annotate mode.
Jev Integrations & Adapters#community#awesomejev#catalog-import
5GitHub stars
Ruby gem that groups noul, choice, and score questions into one parallel Jev query, exposing a typed result plus raw probabilities.
Jev Repos & SDKs#community#awesomejev#catalog-import
3GitHub stars
Go utilities for TypeSafe with a standard-library-only client plus qgrep for files and qlog for Kubernetes pod logs.
Jev Tools & CLIs#community#awesomejev#catalog-import
3GitHub stars
.NET port of the JavaScript SDK that batches Choice, Score, and Noul questions in one call, resolved by explicit options, environment, then defaults.
Jev Repos & SDKs#community#awesomejev#catalog-import
3GitHub stars
A local, trainable implementation of the System One decision contract on a 0.5B model: you send state plus closed questions and get one discrete answer per question by scoring option tokens instead of generating JSON.
Jev Tools & CLIs#community#awesomejev#catalog-import
3GitHub stars
Mailbox triage proof-of-concept: a local fake IMAP server feeds a listener that asks Jev one batched call per email, and plain Python turns the answers into labels that a single-file dashboard shows.
Jev Agents & MCP#community#awesomejev#catalog-import
2GitHub stars
A Chrome extension that scores X posts and replies as they enter the viewport, judging the author's handle, display name and bio alongside the post text and, for replies, the parent post.
Jev Demos & Experiments#community#awesomejev#catalog-import
3GitHub stars
A character-level language model assembled out of a classifier: the vocabulary becomes 28 Choice options, a to z plus space and stopping, and generation is the ordinary autoregressive loop.
Jev Tools & CLIs#community#awesomejev#catalog-import
5GitHub stars
A CUDA-native decision engine that turns an open Qwen3.5 checkpoint into a System One endpoint with Jev's wire format, answering many typed questions per state from C and CUDA with no PyTorch at runtime.
Jev Practices & Patterns#community#awesomejev#catalog-import
4GitHub stars
A DeepSeek Harness plugin that replaces DSH's size-based context compaction with Jev judgments: tool results that are still needed are never trimmed however large, and spent ones get a code-written receipt instead of a model-written summary.
Jev Agents & MCP#community#awesomejev#catalog-import

Start here with Jev

Hand-picked entries the maintainers recommend first, from official primitives to community tools.

Published evaluations of four automation workflows, security incidents, agent trace observability, invoice processing, and customer service, comparing Jev and frontier LLMs as structured workflows versus single prompts.
Jev Practices & PatternsDocs#official#benchmarks#evaluation
Official
6GitHub stars
.NET SDK for the System One API with typed question sets, HttpClientFactory and dependency-injection wiring, plus Microsoft.Extensions.AI guardrail, routing, tool, and evaluator adapters.
Jev Repos & SDKs#community#sdk#csharp
A NativeAOT-ready .NET SDK generated from TypeSafe's OpenAPI definition, with typed question sets, batching, dependency injection, and Microsoft.Extensions.AI integrations.
Jev Repos & SDKs#community#sdk#csharp

Watch: Jev in action

Walkthroughs, tests, and demos from the community.

YouTube: KodeKloud's three-minute primer: what a System One model decides, and why it answers in milliseconds.

YouTube: Caleb Writes Code explains what Jev is and how to call it, in seven minutes.

YouTube: Greg Isenberg and Ryan Vogel on the businesses Jev unlocks, and a path in through the Vercel AI Gateway.

YouTube: CJ from Syntax demos browser use, classification, code review, a model router, and a chat bot with no LLM.

YouTube: Ryan Vogel runs Jev on 100 and then 1,000 emails: category, priority, spam, and reply predictions.

YouTube: AICodeKing tests support routing, refund detection, prompt-injection resistance, and browser automation.

Discussions about Jev

Threads from Reddit and Hacker News about building with Jev.

Hacker News: Show HN: Ad Spend Guard gates budget before the auction, not the creative after.

Show HN: Gating ad budget with a decision modelRead the thread on Hacker News

Reddit: Reranking rebooking options with a decision model, ranked with reasons.

Hacker News: Pick Verify: a single decision at the warehouse pick station catches confusable picks.

Show HN: Verifying robot picks with a decision modelRead the thread on Hacker News

Hacker News: Software Bombe and live Enigma demo where Jev ranks cribs and judges plaintext.

ag_212 pointsShow HN: Jev as the Bletchley Park Analyst: A Software Bombe on EnigmaRead the thread on Hacker News

Hacker News: Show HN for the decide CLI: brew install, file context, and multi-question shell scripts.

vsekhar2 pointsShow HN: Decide – Jev decisions in the shell, scripts, and agent skillsRead the thread on Hacker News

How entries are chosen

Every entry is hand-picked against the same bar, whether it comes from TypeSafe or the community.

  • Public and working — no paywalls, sign-up walls, or dead links.
  • Concrete — it has to be about Jev and the System One API, not generic LLM content.
  • Useful today — something a developer can learn from or use right now.
  • Distinct — if a similar entry exists, the description has to say what makes this one different: a different runtime, a cheaper path, a measured result, or a narrower focus.
  • Documented — repos state their license, and docs are in English or carry an English summary.

Spam, affiliate links, and thin AI-generated content are rejected. New entries are expected to ship with a deep dive: two to five highlights, caveats, a quickstart snippet where one helps, and a verification date. Star counts are refreshed when an entry is touched.

Common questions

Short answers about Jev and how this directory works.

What is Jev?

Jev is TypeSafe AI's first System One model. It takes a state plus typed questions and returns one structured answer per question — a choice, an ordered score, or the probability of yes — with calibrated confidence on Choice and Score answers, so code can branch on the result without parsing generated text.

What is the difference between Choice, Score, and Noul?

They are the three question primitives. Choice picks one of up to 255 options, Score rates on 2 to 10 ordered levels, and Noul answers yes or no. Choice and Score answers carry a confidence between 0 and 1; a Noul answer is the probability of yes.

Which Jev SDKs and client libraries are available?

TypeSafe maintains official JavaScript/TypeScript and Python SDKs plus a Python adapter. The community has built clients for Go, .NET, PHP, Laravel, Rust, Elixir, Ruby, and Scala, along with framework integrations such as DSPy, LlamaIndex, and Home Assistant. All of them are listed in the Repos & SDKs category.

Is the directory free, and is it affiliated with TypeSafe AI?

The directory is free to browse: every entry is hand-picked, and spam, affiliate links, and sign-up walls are rejected. JevDirectory.org is community-run and not affiliated with TypeSafe AI — Jev and System One are TypeSafe AI trademarks.

How often is the directory updated?

Entries are added as new resources appear and re-checked when they are touched. The directory currently holds 2231 entries from 148 source sites, last updated Oct 12, 2026.

What is a verified deep dive?

Most entries include a deep dive: two to five highlight bullets someone would only know from using the resource, a caveats note about limits and requirements, an optional quickstart snippet, and the date the link was last checked. 2231 of the 2231 entries carry one today.

For the canonical details, read the official TypeSafe docs and the API reference.

From the Jev community

Posts from builders shipping with Jev right now.

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