Skip to content

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 49–96 of 625 resources

30GitHub stars
Rust CLI that checks each PDF page for a usable text layer, extracts text pages locally, sends only the rest to an OCR model via LiteLLM, and merges a page-ordered result.
Jev Tools & CLIs#community#jevbest#catalog-import
27GitHub stars
Local-first trading journal and review harness that is read-only over markets, captures runs into frozen envelopes and evidence packs, and requires explicit human promotion before any rule returns.
Jev Tools & CLIs#community#jevbest#catalog-import
25GitHub stars
Agent runtime with a terminal UI and a messaging gateway that keeps memory, self-built skills, session search, scheduling, and subagents across Telegram, Discord, Slack, WhatsApp, Signal, and CLI.
Jev Integrations & Adapters#community#jevbest#catalog-import
47GitHub stars
Zero-dependency Node 22 adapter that puts typed Jev decisions beside any LLM, with swappable backends, confidence gates, MCP tools, an ACP sidecar, and offline-ready recipes.
Jev Demos & Experiments#community#jevbest#catalog-import
30GitHub stars
Side-by-side game harness where Laya running locally and Jev over API answer the same typed questions for snake, kombat, runner, flappy, tetris, and human-versus-model matches.
Jev Demos & Experiments#community#jevbest#catalog-import
40GitHub stars
Python decision client exposing Choice, Noul, and Score primitives with isolated order-invariant scoring, a deliberative flywheel that crystallizes hard cases into fast paths, and local or hybrid deployment.
Jev Demos & Experiments#community#jevbest#catalog-import
27GitHub stars
SwiftPM client for the TypeSafe System One API that mirrors the official JavaScript SDK, with typed Choice, Noul, and Score questions over Codable answers.
Jev Repos & SDKs#community#jevbest#catalog-import
72GitHub stars
MCP server over stdio that gives coding agents fourteen Jev judgment tools, turning evidence plus an enumerable question into auto, review, or escalate actions from calibrated probabilities.
Jev Agents & MCP#community#jevbest#catalog-import
29GitHub stars
Static aggregation site and JSON dataset collecting Jev posts, demos, long-form pieces, and discussions from X with original links and author credit and no rehosted content.
Jev Guides & Articles#community#jevbest#catalog-import
22GitHub stars
Local browser-agent extension where FX plans tasks and Jev picks constrained actions from observed elements, with model calls routed through Vercel AI Gateway.
Jev Demos & Experiments#community#jevbest#catalog-import
36GitHub stars
Small decision model that returns per-answer probabilities for yes/no, 2-255 choices, or 2-10 level scores in one prefill over the SystemOne format.
Jev Demos & Experiments#community#jevbest#catalog-import
53GitHub stars
Rust server that exposes a System One compatible API at /v1/systemone for self-hosted Laya checkpoints with token-based batching.
Jev Demos & Experiments#community#jevbest#catalog-import
32GitHub stars
Design sampler that turns a one-line prompt into a canvas of full-page screens by asking Jev to pick among fixed shadcn layouts instead of writing code.
Jev Demos & Experiments#community#jevbest#catalog-import
51GitHub stars
GraphRAG layer that runs a 4-phase ingest-to-answer pipeline over Neo4j, Memgraph, AGE or Kuzu using Laya or Jev decisions instead of per-hop LLM calls.
Jev Integrations & Adapters#community#jevbest#catalog-import
33GitHub stars
SillyTavern extension that sends chat text to Jev sensors and fires one rule action per turn such as nudging, rerolling, editing lists, or running scripts.
Jev Integrations & Adapters#community#jevbest#catalog-import
22GitHub stars
Terminal harness that checks ROS 2 robots with deterministic health tests, capability descriptions, SQLite history, and optional Jev evidence routing.
Jev Demos & Experiments#community#jevbest#catalog-import
34GitHub stars
Local server for typed-decision models that answers many Jev questions in one forward pass with checkpoint routing and micro-batching.
Jev Demos & Experiments#community#jevbest#catalog-import
39GitHub stars
Video tool where Jev scores subtitle segments and code assembles a short highlights cut plus a de-watered full cut with timestamped summaries.
Jev Tools & CLIs#community#jevbest#catalog-import
22GitHub stars
Browser extension that scores social hooks keystroke by keystroke with Jev curiosity, emotion, pattern and clickbait checks plus short fix tips.
Jev Demos & Experiments#community#jevbest#catalog-import
Android chat client and SillyTavern-compatible endpoint with prefix-cache fixes, layered memory, plugins, and Jev-assisted screening.
Jev Tools & CLIs#community#jevbest#catalog-import
Research runtime that pages a large logical tool and context space through a small bounded Jev decision surface with explicit approvals.
Jev Agents & MCP#community#jevbest#catalog-import
29GitHub stars
DuckDB extension that asks a Jev question about every row in SQL and returns a typed ENUM, DOUBLE, or STRUCT column instead of generated text.
Jev Integrations & Adapters#community#jevbest#catalog-import
30GitHub stars
Forkable weekday radar that asks Jev one yes-or-no question per interest over each new arXiv announcement and publishes a page plus RSS feed.
Jev Tools & CLIs#community#jevbest#catalog-import
44GitHub stars
Pi extension that keeps a fast Executor model on implementation and brings in a separate Advisor model for consequential choices and reviews.
Jev Agents & MCP#community#jevbest#catalog-import
21GitHub stars
Pi guard plugin that checks inputs and tool calls with local rules plus Jev semantic judgements, with redaction and verification reminders.
Jev Demos & Experiments#community#jevbest#catalog-import
70GitHub stars
Self-hosted proxy that records typed decisions, distils them into small heads on a frozen encoder, and answers locally when confident.
Jev Demos & Experiments#community#jevbest#catalog-import
21GitHub stars
Rust CLI that sends selected source to the Jev API under JSON-defined choice rules and maps answers to warnings or errors.
Jev Agents & MCP#community#jevbest#catalog-import
18GitHub stars
Local engine with TypeScript and Python SDKs that runs Claude Code and Codex sessions as a warm team with a durable mailbox.
Jev Agents & MCP#community#jevbest#catalog-import
22GitHub stars
Zero-dependency client that turns any logprobs-capable chat endpoint into typed choice, boolean, and score decisions with abstention.
Jev Demos & Experiments#community#jevbest#catalog-import
18GitHub stars
Desktop workspace for AI-assisted development that pairs Codex conversations with local CodeGraph indexes, plus editing, Ghostty terminal panes, and Git in one app.
Jev Tools & CLIs#community#jevbest#catalog-import
21GitHub stars
Skill pack for Codex, Claude Code, and WorkBuddy that drives CNKI topic search, result parsing, detail reading, downloads, citation export, screening tables, and resumable task ledgers.
Jev Agents & MCP#community#jevbest#catalog-import
24GitHub stars
Unofficial laptop study of parallel constrained decoding: prefill once, share the KV cache across fields, and decide all schema fields in one batched forward pass without writing JSON.
Jev Practices & Patterns#community#jevbest#catalog-import
17GitHub stars
Pi extension that trims wasted context before each model call by deduplicating repeated tool results, stripping failed payload args, and letting the model summarize closed spans.
Jev Tools & CLIs#community#jevbest#catalog-import
12GitHub stars
Local decision engine that answers letter-choice questions from one forward pass: shared prefill, one batched decode, and softmax over option letters with no text generation or repair.
Jev Demos & Experiments#community#jevbest#catalog-import
24GitHub stars
Native macOS computer-use agent on Apple silicon that finds controls with local CoreML detection, OCR, and accessibility, then asks Jev to pick the next finite-choice action.
Jev Demos & Experiments#community#jevbest#catalog-import
42GitHub stars
Open harness that renders allowed JSON answers on a diffusion canvas, denoises for a fixed step budget, then picks the top allowed tokens from final logits with no training.
Jev Demos & Experiments#community#jevbest#catalog-import
38GitHub stars
Async supervisory layer for Hermes Agent that locks Definitions of Done, proves mechanical criteria locally, and calls Jev only for unresolved semantic checks under a token budget.
Jev Tools & CLIs#community#jevbest#catalog-import
Browser drone-fleet lab where TypeSafe Jev steers each drone as fast reflexes and an optional planner offers one-use strategy advice when confidence drops, without pausing control.
Jev Demos & Experiments#community#jevbest#catalog-import
16GitHub stars
Single-command harness that turns a plain-language stack description into synced docs plus blocking hooks for Claude Code, Codex, and Pi, with deterministic presets or one Jev chooser call.
Jev Agents & MCP#community#jevbest#catalog-import
18GitHub stars
CPU port of the SemIf decision pattern with a browser UI: type state and runtime criteria, then read typed option probabilities from one open-model forward pass with no GPU.
Jev Demos & Experiments#community#jevbest#catalog-import
19GitHub stars
Six side-by-side web demos where Jev returns typed probabilistic decisions, plain code owns routing, and a switchable small model writes the words for Claude or Kimi tiers.
Jev Demos & Experiments#community#jevbest#catalog-import
Python CLI and MCP server for keyless web search over DuckDuckGo or self-hosted SearXNG, with an optional local Laya sieve that filters, reranks and stance-checks evidence before it reaches an agent.
Jev Agents & MCP#community#jevbest#catalog-import
24GitHub stars
macOS floating WeChat companion that reads the visible chat with on-device Vision OCR, judges intent and reply risk with Jev, drafts toned replies with GPT, and only fills text after you approve it.
Jev Tools & CLIs#community#jevbest#catalog-import
19GitHub stars
Community index of shipped Jev decision-model projects across workflow, bulk, realtime, verify, harness and voice patterns, with official docs, SDKs and per-link rubric scoring.
Jev Guides & Articles#community#jevbest#catalog-import
25GitHub stars
Jev decision layer for DeepSeek Harness that narrows visible tools, gates risky calls, guards retry loops and routes models, with Jev permitted only to restrict or gate, never to widen access.
Jev Agents & MCP#community#jevbest#catalog-import
41GitHub stars
Open MIT family of typed-decision models in 4B and 27B with GPU and Apple Silicon builds, answering structured questions in one forward pass with calibrated per-option probabilities.
Jev Demos & Experiments#community#jevbest#catalog-import
16GitHub stars
Self-hosted OpenAI-compatible router on port 8787 that sends each prompt to the cheapest capable model across free, budget, mid and premium tiers, with heuristic auto and Jev-backed routing modes.
Jev Agents & MCP#community#jevbest#catalog-import
23GitHub stars
Live race rig that labels 1,000 real app reviews with Jev typed questions against Gemini JSON output on identical batches, then replays recordings and re-ranks rows locally without extra model calls.
Jev Practices & Patterns#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.

Follow @typesafeai