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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 12 of 2231 resources

A warehouse pick-verification step that compares a scanned item, the bin's expected contents, and the order line to decide between accept and re-scan, catching confusable picks a barcode alone would pass.
Jev Integrations & Adapters#community#python#robotics
Community
3GitHub stars
Measured robotics study that runs Jev as the decision layer for a 10,000-robot warehouse fleet over 41 bilingual incident templates and publishes a crossover against a self-hosted ModernBERT: 0.527 s p50, $24.57 per million decisions, and 91.3% agreement with template labels.
Jev Benchmarks & Evaluations#community#robotics#fleet-triage
21GitHub stars
Multimodal finite-choice decision interface and MuJoCo robotic-arm workbench: dual-camera images and state go to a self-hosted Qwen3.5-9B with a corrective head, which returns one typed next-skill choice without generating text.
Jev Models & Reimplementations#community#robotics#multimodal
1GitHub stars
MuJoCo simulation where a local decider-2b model picks the next skill for an AgileX PiPER arm through a Jev-style typed-choice interface while the red cube target is pushed to new positions mid-run. Deterministic checks may reject a chosen skill but never substitute another.
Jev Demos & Experiments#community#robotics#simulation
Dan Makes Things wires an ESP32 robot so Jev picks the next move, and asks whether it is the first robot controlled that way.
Jev Demos & ExperimentsVideo#community#video#robotics
Community
12GitHub stars
A ManiSkill demo where plain-English goals drive a simulated Franka Panda: Jev picks one primitive per step from a catalog of about 30 hardcoded skills, and Python executes the move. No training or policy.
Jev Cookbooks#community#python#robotics
257GitHub stars
A Python CLI that connects multiple robots under one contract with an optional Jev stepper: Jev picks among permitted discrete calls while an LLM writes poses and prose and the executor enforces safety gates.
Jev Tools & CLIs#community#python#robotics
287GitHub stars
A MuJoCo and Franka Panda workbench where Jev chooses the next manipulation step for pick-and-place, stacking, and obstacle-carry tasks, with rule baselines and side-by-side model comparison.
Jev Cookbooks#community#python#robotics
57GitHub stars
Two-stage Jev control of a Franka Panda in MuJoCo: Jev selects a task intent, then X/Y/Z directions and a gripper command executed against real contacts, with 43 of 50 Jev episodes succeeding versus 48 of 50 for a rule baseline.
Jev Cookbooks#community#python#robotics
4GitHub stars
An SO-101 workbench where an evaluation model or rules baseline picks bounded joint steps from typed candidate actions: decision runs are spend-capped via the Vercel AI Gateway and drive a real LeRobot arm or mock hardware.
Jev Cookbooks#community#typescript#robotics
80GitHub stars
A fine-grained robot control study loop for LIBERO tasks: Jev layers an intent, a contact or motion family, and one of 27 control inputs, while reversible MuJoCo previews evaluate each candidate before execution.
Jev Cookbooks#community#python#robotics
266GitHub stars
A camera-only MuJoCo quadrotor that uses Jev for tactical maneuvers at 2.5 Hz while classical perception and a 50 Hz reflex layer keep safety outside Jev, clearing a five-station course.
Jev Cookbooks#community#python#robotics

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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