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.
- Repos & SDKs202Client libraries, adapters, and source code you can build on with Jev, from the official Python and TypeScript SDKs to community ports in Go, .NET, and PHP.
- Integrations & Adapters145Framework, platform, gateway, and database integrations that put Jev inside the stack you already run, from LangChain and Pydantic AI to Postgres and Home Assistant.
- Agents & MCP302Agent runtimes, coding-agent gates and routers, MCP servers, and skill or context tooling that hand an agent Jev's typed decisions.
- Tools & CLIs447Standalone Jev CLIs, desktop apps, playgrounds, and utilities you run directly, from shell history and semantic search to dashboards and meters.
- Cookbooks91Official, runnable Jev recipes that show what decision models are good at, each with its own datasets, latencies, and numbers.
- Demos & Experiments363Playable demos, games, simulators, and experiments that put Jev in the loop, from Mario and drones to moderation firehoses and trading bots.
- Practices & Patterns248How to design Jev states, questions, and confidence gates the right way, from the official patterns to the failure modes worth designing around.
- Guides & Articles224Documentation, write-ups, and community hubs for learning Jev, from the canonical docs to independent tutorials and reviews.
- Benchmarks & Evaluations55Benchmarks, calibration studies, independent evaluations, and observability write-ups that measure how Jev actually behaves.
- Models & Reimplementations99Open reimplementations of Jev, retrained heads on small models, and inference-time tricks that reproduce the System One shape with other weights.
- Media & Talks55Videos, talks, podcasts, and news coverage about building with Jev.
Browse Jev by use case or industry
The same directory, sliced by what you are building and who you are building it for.
All 2231 Jev resources
Search the full directory, or filter by category and tag.
Showing 625–672 of 954 resources
1GitHub stars
A Letta agent skill that wraps TypeSafe System One (Jev) as a cheap external judge for texts and decisions, plus a paragraph scanner that maps where a document argues, lists, asks, or admits uncertainty. The README is in Russian.
Jev Integrations & Adapters#community#jevbest#catalog-import
2GitHub stars
A Next.js workbench that converts OpenAI-compatible Chat Completions requests into Jev state and typed questions, compares chat output against structured judgments, and publishes saved question packs as proxy routes. The interface is mainly in Chinese.
Jev Integrations & Adapters#community#jevbest#catalog-import
Community
Chandler-Sun/chat2jevTypeScript
Chandler-Sun/chat2jevTypeScript1GitHub stars
An evidence and reproduction package for a Jev decision study: the original fixed-split result on DBLP to ACM entity matching and SciFact relation verification, a later fresh repeat that did not resolve it, and the graph-synthesis work that followed.
Jev Practices & Patterns#community#jevbest#catalog-import
Community
CompleteDotTech/paper-packagePython
CompleteDotTech/paper-packagePython1GitHub stars
An Oh-my-pi extension that asks Jev which parts of large tool results are worth keeping before they enter the main model's context, and can also trim earlier plain-text assistant messages, keeping the original text locally for exact recovery.
Jev Agents & MCP#community#jevbest#catalog-import
Community
d3d0n/omp-statifyTypeScript
d3d0n/omp-statifyTypeScript4GitHub stars
A single-file host agent skill that reports what another skill's next closed decision would be, with a confidence and a probability over every outcome, by asking Jev to choose rather than by running the target skill at all.
Jev Agents & MCP#community#jevbest#catalog-import
3GitHub stars
A local markdown mirror of the TypeSafe documentation plus Lume, a Rust search tool that indexes it with BM25 and a tag graph, so pattern-style queries such as intent routing can walk to the right page without a network round trip.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
DeepBlueDynamics/typesafe-arenaRust
DeepBlueDynamics/typesafe-arenaRust2GitHub stars
A Chrome extension that asks Jev closed yes/no questions about the pages you browse and hangs a label on each item from a rule pack, with per-site sensitivity, read-ahead, optional fading or hiding, and a tuning mode that shows how every judgment was reached.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
elpumberto/barruntoTypeScript
elpumberto/barruntoTypeScript1GitHub stars
Two frozen open-weight Qwen3.5 models read each task four ways, a letter and a pair readout each, and a fit-free fusion plus an agreement router turn those readings into calibrated decisions, with no fine-tuning and no distillation anywhere in the pipeline.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
FeiLiuEM/tetrajevPython
FeiLiuEM/tetrajevPython9GitHub stars
An SRT translator and subtitle QC tool: cue numbers, order and timestamps are preserved locally, missing translations are retried by ID, and Jev flags each source and translation pair that may deserve human review. Web UI or CLI.
Jev Tools & CLIs#community#jevbest#catalog-import
1GitHub stars
A Claude Code plugin that verifies every tool call before it runs, asking Jev five parallel questions about the plan, scope, prior action and stated intent, then allowing, asking or blocking. Fresh installs ship in audit mode.
Jev Agents & MCP#community#jevbest#catalog-import
Community
getexcited/stepwardenTypeScript
getexcited/stepwardenTypeScript2GitHub stars
A .NET 10 and React 19 support-ticket triage application: one batched Jev call yields five typed decisions, a deterministic rule engine makes the final call, and every field reports whether the model or a rule decided it. Accepts Persian and English.
Jev Tools & CLIs#community#jevbest#catalog-import
Community
GhrezaKh74/JevTicktRouterC#
GhrezaKh74/JevTicktRouterC#1GitHub stars
Python adapter that turns an existing LLM into a bounded decision function: define one question and its answers, get scores, optionally calibrate on your own examples, then abstain below a threshold you set.
Jev Practices & Patterns#community#jevbest#catalog-import
Community
grishahq/decisionbridgeHTML
grishahq/decisionbridgeHTML1GitHub stars
Unofficial Go SDK for TypeSafe AI's System One API, kept deliberately minimal: one client, a state map, a map of typed questions, and answers read back by question id.
Jev Repos & SDKs#community#jevbest#catalog-import
Community
guillemus/jev-goGo
guillemus/jev-goGo10GitHub stars
An independent typed-decision server built on Google's DiffusionGemma and SGLang: it reads image pixels as well as text, returns choice, noul and score answers, and ships a drawing playground and local evaluation artifacts.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
Hangzhi/diffusion-jev-sglangPython
Hangzhi/diffusion-jev-sglangPython1GitHub stars
A stunt build where C is compiled and run on a simulated SERV RISC-V CPU whose logic gates are lookup tables of 22 boolean answers that Jev fills in, with the clock, trace and cost on screen.
Jev Practices & Patterns#community#jevbest#catalog-import
Community
i2cjak/RISC-jeVPython
i2cjak/RISC-jeVPython1GitHub stars
A pre-release .NET decision library that keeps the domain in a dependency-free Core assembly and reaches Jev through a pluggable provider, so changing vendors does not mean rewriting your application model.
Jev Repos & SDKs#community#jevbest#catalog-import
Community
iamjonatha/decisionkit-dotnetC#
iamjonatha/decisionkit-dotnetC#10GitHub stars
Two pi extensions driven by Jev judgments: one replaces summary-based context compaction with keep, drop and shorten calls, the other scores each prompt for difficulty and switches pi's model before the turn runs.
Jev Agents & MCP#community#jevbest#catalog-import
Community
iefnaf/pi-jevTypeScript
iefnaf/pi-jevTypeScript2GitHub stars
A Tauri desktop workspace for running coding agents side by side: parallel task queues in isolated Git worktrees, your existing agent sign-ins, and a review step before anything is merged.
Jev Tools & CLIs#community#jevbest#catalog-import
Community
Jackalope-Dev/jackalopeRust
Jackalope-Dev/jackalopeRust3GitHub stars
A Home Assistant Assist conversation agent that sends each command to Jev as one request with a speculative fan-out of questions, then hands the typed answers to Home Assistant's own intents to do the device control.
Jev Integrations & Adapters#community#jevbest#catalog-import
Community
JanOstrowka/typesafe-assistPython
JanOstrowka/typesafe-assistPython1GitHub stars
A small stdio MCP server that exposes three Jev-backed tools to coding agents: structured judgments, ranking supplied candidates by relevance, and checking claims against evidence you provide.
Jev Agents & MCP#community#jevbest#catalog-import
Community
jbt95/jev-toolkitTypeScript
jbt95/jev-toolkitTypeScript1GitHub stars
An unofficial async Rust client for the TypeSafe System One API in which each question hands back a key typed by its answer, so reading a choice answer as a probability fails to compile.
Jev Repos & SDKs#community#jevbest#catalog-import
Community
JedimEmO/typesafe-clientRust
JedimEmO/typesafe-clientRust3GitHub stars
A CLI that sends state plus typed questions to Jev and prints structured JSON, with boolean, choice and score question types, a documented exit-code contract for CI, and an optional Vercel AI Gateway transport.
Jev Tools & CLIs#community#jevbest#catalog-import
Community
jtsang4/jev-cliTypeScript
jtsang4/jev-cliTypeScript4GitHub stars
A CLI and agent skill that asks plain-English questions across a repository, sends each in-scope chunk to the provider, returns scored source locations to investigate, and runs recurring review rules on diffs.
Jev Agents & MCP#community#jevbest#catalog-import
Community
Kelbie/hunchTypeScript
Kelbie/hunchTypeScript3GitHub stars
An experiment that composes TypeSafe Jev Choice decisions into free-form text: every next character becomes one typed decision over 98 options, with branch backtracking and a final complete/incomplete check.
Jev Practices & Patterns#community#jevbest#catalog-import
Community
kesku/jev-freeformJavaScript
kesku/jev-freeformJavaScript1GitHub stars
A Python search command for terminals and agents: Parallel Search seeds queries, a local Chromium fetches pages concurrently, and Jev scores the evidence to expand a breadth-first link queue. Ships readable output, JSON and an MCP server.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
komikat/psearchPython
komikat/psearchPython10GitHub stars
A research reproduction of the Jev question shape — Choice, Score and Noul answered in one forward pass — trained and measured side by side on encoder backbones and a diffusion LLM, with accuracy, calibration, latency and training cost in one table.
Jev Practices & Patterns#community#jevbest#catalog-import
Community
kotoba-lang/typed-decisionsPython
kotoba-lang/typed-decisionsPython1GitHub stars
A FastAPI plus React lab where Jev picks each 2048 move through one choice decision per turn, running many games in parallel with a live best score and a browser editor for the exact state payload Jev sees.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
KyleKreuter/jev2048TypeScript
KyleKreuter/jev2048TypeScript1GitHub stars
A minimal Next.js workbench for Jev: paste a state, mix noul, choice and score questions, and see the typed answers, probability distributions and confidence returned from a single parallel request.
Jev Demos & Experiments#community#jevbest#catalog-import
2GitHub stars
A TypeScript decision layer for agent loops that reads yes/no, one-of-n and rubric answers off one token's probabilities from a local logprobs model, with a permission gate shipped as a Claude Code plugin.
Jev Agents & MCP#community#jevbest#catalog-import
Community
liu-x27/XavierJevTypeScript
liu-x27/XavierJevTypeScript4GitHub stars
A LangChain agent where Jev routes intent as a typed choice over four fixed criteria, with confidence below 0.6 falling back to local keyword rules, and each route carrying exactly one tool and one prompt.
Jev Agents & MCP#community#jevbest#catalog-import
6GitHub stars
An unofficial Java 21 client for the Jev decision API that replaces maps with records and sealed types, so a malformed choice, score or noul question fails to compile instead of coming back as a 422.
Jev Repos & SDKs#community#jevbest#catalog-import
Community
luigivis/jev-sdk-javaJava
luigivis/jev-sdk-javaJava1GitHub stars
A Rust filter that reads JSONL security alerts on stdin and asks five Jev questions per alert — disposition, severity, false positive, escalation, ATT&CK class — then applies the routing policy in ordinary code you control.
Jev Tools & CLIs#community#jevbest#catalog-import
Community
m0rphtail/triagedyRust
m0rphtail/triagedyRust4GitHub stars
A Rust CLI of Jev experiments, led by a PHI screener that judges four separate 45 CFR 160.103 metrics per file and an English part-of-speech tagger that batches only the unresolved words into one request.
Jev Demos & Experiments#community#jevbest#catalog-import
2GitHub stars
An agent tool and MCP call gate: paste a planned call plus its context and it returns allow, ask_human or deny with risk scores derived from a TypeSafe Jev decision call.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
ndolinschi/toolgateTypeScript
ndolinschi/toolgateTypeScript1GitHub stars
A Bun and Next.js moderation demo that screens text with one systemOne call — seven hazard Nouls plus a severity Score in parallel — and computes the verdict in code from policy thresholds.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
NorbertBodziony/guard-jevTypeScript
NorbertBodziony/guard-jevTypeScript1GitHub stars
A CLI that reads the comments in your JS/TS files with the code around them and scores each one for accuracy and usefulness out of 100, weakest first, using Jev.
Jev Tools & CLIs#community#jevbest#catalog-import
Community
ntedvs/commentcopTypeScript
ntedvs/commentcopTypeScript1GitHub stars
A PowerShell hook for Codex that intercepts your prompt turn and asks Jev to audit the conversation recorded so far, answering with typed probabilities rather than prose.
Jev Agents & MCP#community#jevbest#catalog-import
Community
omni-/ask-jevPowerShell
omni-/ask-jevPowerShell2GitHub stars
A Game of Thrones roleplay where a narrator model writes each scene and Jev answers five typed questions about it, with the location, music, artwork and next prompt all following from those answers.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
phureewat29/got-jevTypeScript
phureewat29/got-jevTypeScript2GitHub stars
Screens MEDLINE titles and abstracts for an ADHD systematic review with Jev, scored against the Cohen 2006 Abstract Triage gold labels, with a published rule rather than a bare model verdict.
Jev Practices & Patterns#community#jevbest#catalog-import
1GitHub stars
An unofficial MCP server exposing one ask tool: your agent hands Jev some material and a list of plain questions, and gets typed answers with probabilities back in one round trip.
Jev Agents & MCP#community#jevbest#catalog-import
Community
pZacca/askjevTypeScript
pZacca/askjevTypeScript2GitHub stars
A TypeScript client for Jev where every decision must handle an unsure branch, so a low-confidence answer escalates instead of collapsing silently into a boolean.
Jev Tools & CLIs#community#jevbest#catalog-import
Community
qddegtya/qualmTypeScript
qddegtya/qualmTypeScript3GitHub stars
An MCP server with a single evaluate_decision tool that returns noul, choice or score probabilities over a diff, log or plan, with output tokens set to zero on every call.
Jev Agents & MCP#community#jevbest#catalog-import
2GitHub stars
Ten runnable JavaScript experiments on agent decisions, each pairing a small Jev judgment with visible application policy code, plus authored fixtures so the whole set runs offline.
Jev Demos & Experiments#community#jevbest#catalog-import
1GitHub stars
A zero-dependency Node proxy that sits in front of Jev, forwards every request unchanged, and reports whether a local decision model would have made the same call on your own traffic.
Jev Practices & Patterns#community#jevbest#catalog-import
1GitHub stars
A directory of projects built on Jev, grouped into SDKs, integrations, agent tooling, applications and research, where each repository is classified by the model itself.
Jev Guides & Articles#community#jevbest#catalog-import
Community
rhc98/awesome-jevTypeScript
rhc98/awesome-jevTypeScript5GitHub stars
An inference-only prototype of a Jev-style decision model on a sub-billion-parameter hybrid backbone, returning typed probability distributions in one forward pass, with its architecture treated as an explicit guess.
Jev Practices & Patterns#community#jevbest#catalog-import
Community
shamazharikh/qwen-rlcdPython
shamazharikh/qwen-rlcdPython1GitHub stars
A static HTML dashboard, four commits deep, scoring Jev against two luna variants on Japan's 2026 Common Test. The repo is results only: CSV tables, one JSON file and two HTML pages, with no scripts to regenerate them.
Jev Practices & Patterns#community#jevbest#catalog-import
Community
shibadogcap/kyotsu-ai-benchHTML
shibadogcap/kyotsu-ai-benchHTML14GitHub stars
Claude Code hook that asks Jev which installed skill fits each prompt and logs the answer, plus the script that joins that log to session transcripts and the negative result the author got from a week of running it.
Jev Agents & MCP#community#jevbest#catalog-import
Community
shimo4228/jev-skill-routerPython
shimo4228/jev-skill-routerPythonStart 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
Community
Hawxy/TypeSafeAI.NetC#
Hawxy/TypeSafeAI.NetC#0GitHub stars
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
Community
tryAGI/TypeSafeAIC#
tryAGI/TypeSafeAIC#Newest Jev resources
The latest additions to the directory, newest first.
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 NewsReddit: 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 NewsHacker News: Decision Index 0.2.1 scores open reproductions of Jev on a frozen suite.
jackbravo4 pointsDecision Index 0.2.1 – 70 open reproductions of TypeSafe Jev's Decision ModelRead the thread on Hacker NewsHacker 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 NewsHacker 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 NewsHow 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.