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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

Search the full directory, or filter by category and tag.

Showing 145–192 of 954 resources

16GitHub stars
Shell wrapper that intercepts unknown subcommands, reads the target CLI help output, and asks Jev which documented subcommand matches the intent behind the typo.
Jev Agents & MCP#community#jevbest#catalog-import
72GitHub stars
Open training and deployment stack for System 1 decision models: one state-plus-question-plus-options API that returns a choice with probabilities for tickets, tools, or robot actions.
Jev Demos & Experiments#community#jevbest#catalog-import
275GitHub stars
Self-rebuilding Jev index organized by evidence grade, with one ranked pick per category, multilingual guides, and links through to full cards and sources.
Jev Guides & Articles#community#jevbest#catalog-import
19GitHub stars
Windows desktop aid that reads the local WeChat database for the foreground chat, strips identifiers, and asks Jev for stage, intent, tension, suggested moves, and a reply review.
Jev Tools & CLIs#community#jevbest#catalog-import
48GitHub stars
Next.js dashboard plus Python feed that streams market data, computes indicators across timeframes, sends enabled states to Jev, and applies the judgments to a SQLite paper portfolio.
Jev Tools & CLIs#community#jevbest#catalog-import
26GitHub stars
LLM CLI plugin that exposes TypeSafe classification and scoring as a jev model with yes-or-no, category, and rubric-rating calls from shell or Python.
Jev Tools & CLIs#community#awesomejev#catalog-import
23GitHub stars
Coding-agent plugin that routes prompt classification, subagent tiering, edit rule checks, and fast Jev-backed compaction through small typed judgments.
Jev Agents & MCP#community#jevbest#catalog-import
15GitHub stars
Prompt-first symbolic music studio where a live Jev model decides plan, instruments, harmony, groove, and each bar, rendering every pick into an editable multitrack piece.
Jev Tools & CLIs#community#jevbest#catalog-import
15GitHub stars
Uncertainty-aware semantic control flow and routable procedures for Effect, with type-safe patterns and policies over Effect Decision and DecisionModel where uncertain answers stay explicit branches.
Jev Integrations & Adapters#community#jevbest#catalog-import
13GitHub stars
Free starter that teaches turning one document into one small typed decision, built around a fictional travel agency where recorded observations meet inspectable application rules.
Jev Demos & Experiments#community#jevbest#catalog-import
14GitHub stars
Small skill that grills a plan as a design-tree interview, using Jev ad hoc for typed judgments during the session.
Jev Demos & Experiments#community#jevbest#catalog-import
46GitHub stars
Pixel-art simulation engine where agents pick structured next actions through Jev while a separate language model handles dialogue, memory, and beliefs, all running in one browser tab.
Jev Demos & Experiments#community#jevbest#catalog-import
106GitHub stars
Decision layer exposing Jev's typed yes-no, choice, and score answers to DeepSeek Harness and MCP hosts, offline by default with every network transmission disclosed per feature.
Jev Agents & MCP#community#jevbest#catalog-import
14GitHub stars
Self-hosted Decision Lab that asks typed choice, yes-no, and score questions through a browser explorer and a TypeSafe-shaped local API backed by a diffusion checkpoint.
Jev Demos & Experiments#community#jevbest#catalog-import
15GitHub stars
Python prototype that plays NES Super Mario Bros. by sending decoded RAM geometry to Jev, which answers movement and jump questions that code composes into controller buttons.
Jev Demos & Experiments#community#jevbest#catalog-import
12GitHub stars
Single-binary linter whose YAML rules are plain-language questions sent to the Jev model as yes-no judgments with probabilities, fitting CI jobs and pre-commit hooks.
Jev Agents & MCP#community#jevbest#catalog-import
16GitHub stars
Fifty minimal runnable demos pairing Jev's choice, score, and yes-no primitives against a structured-output language-model baseline, each with synthetic scenarios and a small 2D visual.
Jev Demos & Experiments#community#jevbest#catalog-import
941GitHub stars
Type-safe generation layer over existing autoregressive models via JSON Schema on SGLang, returning constrained string, numeric, boolean, and enum answers with optional thinking.
Jev Practices & Patterns#community#jevbest#catalog-import
12GitHub stars
Python bulk-classification helper that packs many independent short texts and one judgment question into fewer Jev requests, aimed at queues of tickets, logs, or labels.
Jev Demos & Experiments#community#awesomejev#catalog-import
17GitHub stars
Command Code mod that asks Jev at every agent stop whether a nudge would help, continuing unfinished work while leaving waits for the user alone.
Jev Agents & MCP#community#jevbest#catalog-import
16GitHub stars
Swift library and CLI for asking Jev typed Choice, Noul, and Score questions from Apple platforms, with answers returned alongside calibrated probabilities in one parallel request.
Jev Repos & SDKs#community#jevbest#catalog-import
12GitHub stars
Programming language and VM where agents run as isolated actors with managed context, durable effects, and confidence-aware control flow, including a Jev decision effect.
Jev Integrations & Adapters#community#jevbest#catalog-import
13GitHub stars
Chrome extension that adds a second Twitch chat column showing only messages Jev rates as matching your chosen intent, with every row linked to its probability distribution.
Jev Demos & Experiments#community#jevbest#catalog-import
16GitHub stars
Standalone terminal agent that puts Jev inside its planning loop, proposing text-model steps and scoring candidates against independent rubrics before a deterministic policy executes one.
Jev Agents & MCP#community#jevbest#catalog-import
12GitHub stars
Command-line checker that asks Jev whether each selected source file violates a plain-English convention, returning file-level probabilities for an agent or CI step to act on.
Jev Integrations & Adapters#community#jevbest#catalog-import
34GitHub stars
Curated catalog of community Jev applications grouped by use, where each case explains the mechanism and states what the public evidence does and does not prove.
Jev Practices & Patterns#community#jevbest#catalog-import
26GitHub stars
Self-hosted scientific wiki that stores paper PDFs in your AWS account, writes one structured evidence note per paper, and answers questions from those notes with citations.
Jev Tools & CLIs#community#jevbest#catalog-import
99GitHub stars
Unofficial PyTorch reconstruction of the ideas behind Jev, encoding state once and answering each question through small typed readout heads in a single parallel pass.
Jev Demos & Experiments#community#jevbest#catalog-import
14GitHub stars
Pi extension that pairs a local coding model with hosted Jev judgments for skill hints, file retrieval, and evidence ranking, with caching and failure bounds on every call.
Jev Agents & MCP#community#jevbest#catalog-import
14GitHub stars
Local Jev-compatible decision server for Macs that reads answer probabilities from Qwen next-token logits in one forward pass, with no text generation or JSON parsing.
Jev Demos & Experiments#community#jevbest#catalog-import
22GitHub stars
Command-line toolkit that wraps Jev judgments into scriptable verify, screen, classify, extract, find, rerank, match, route, ask, compact, and batch commands.
Jev Agents & MCP#community#jevbest#catalog-import
11GitHub stars
TypeScript evaluation utilities that test full AI agent conversations as end-to-end scenarios with binary assertions, without imposing a test runner.
Jev Agents & MCP#community#jevbest#catalog-import
12GitHub stars
Local HTTP API that scores 2-255 candidate options per field with a redistributed ternary GGUF, returning typed Choice, Noul, and Score answers as structured JSON.
Jev Demos & Experiments#community#jevbest#catalog-import
18GitHub stars
Elixir DSL where Gut.feel/4 maps a subject and question to one offered choice, using Jev, any ReqLLM model, local Ollama, or a custom adapter.
Jev Integrations & Adapters#community#jevbest#catalog-import
11GitHub stars
Pi Coding Agent extension that routes only at task boundaries, using Jev judgments plus declared capabilities, availability, price estimates, and failure state.
Jev Agents & MCP#community#jevbest#catalog-import
16GitHub stars
Minimal grammY Telegram bot that sends each new or edited group message to Jev once and deletes only the linked campaign suffix above a 0.81 cutoff.
Jev Tools & CLIs#community#awesomejev#catalog-import
37GitHub stars
Python SDK that runs the same prompt, tools, and MCP setup across DeepAgents, Pydantic AI, Claude Agent SDK, Codex, and OpenCode by switching harness.
Jev Agents & MCP#community#jevbest#catalog-import
40GitHub stars
Claude Code plugin with jev find, jev ask, and a Read hook that keeps large-file context out of the agent by scoring relevance with Jev.
Jev Agents & MCP#community#jevbest#catalog-import
24GitHub stars
Wires Jev into agents as seven MCP tools, an embeddable JevDecisionModel library with run functions, and Claude Code hooks at tool and turn boundaries.
Jev Agents & MCP#community#jevbest#catalog-import
22GitHub stars
Sentence-driven runner where one command is matched to installed reflex programs, planned up front with per-step probabilities and gates.
Jev Agents & MCP#community#jevbest#catalog-import
21GitHub stars
Language and VM for agent programs that wait for approval, survive restarts, and replay portable receipts without recalling the model.
Jev Integrations & Adapters#community#jevbest#catalog-import
12GitHub stars
Semantic lint that checks code against plain-English conventions via Jev and reports file-level violation probabilities for agents and CI.
Jev Agents & MCP#community#jevbest#catalog-import
11GitHub stars
Python browser agent that reads one lean page view per state and answers with a single JSON action, using any OpenAI-compatible model with no decision API or browser daemon.
Jev Practices & Patterns#community#jevbest#catalog-import
19GitHub stars
Capability resolver that uses Jev to search a nested command catalog and return selected instruction context to an agent through one MCP tool, keeping the search outside agent context.
Jev Agents & MCP#community#jevbest#catalog-import
74GitHub stars
Native Swift 6 bridge that evaluates typed Generable structs and enums against app state through on-device Core ML, self-hosted HTTP, or hosted Jev endpoints.
Jev Integrations & Adapters#community#jevbest#catalog-import
19GitHub stars
Rails decision layer that evaluates noul, choice and score questions about app state in one Jev request, with per-question confidence floors that gate auto-action versus human review.
Jev Integrations & Adapters#community#jevbest#catalog-import
24GitHub stars
Curated link collection tracking Jev resources, open reproductions, integrations and architecture playbooks, with every entry resolved from its source thread and checked as a live repo.
Jev Guides & Articles#community#jevbest#catalog-import
21GitHub stars
Browser top-down driving sim that sends sensor JSON to Jev every 200ms with four typed driving questions in one call, then applies confidence gating and reflex rules to steer.
Jev Demos & Experiments#community#jevbest#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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