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The full directory

All Jev AI model resources

Entries for TypeSafe AI's flagship System One model — official docs and SDKs alongside community clients, tools, and write-ups.

Entries
3,889
Categories
11
Official
102
Community
3,787
Source sites
293
Deep dives
3,889

By format

3889
  • Docs169
  • Repos & sites3090
  • Videos74
  • Posts103
  • Articles377
  • Playgrounds76

Updated

Browse the Jev AI model by category

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

All 3889 Jev AI model resources

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Showing 3841–3888 of 3889 resources

A 22-minute walkthrough covering what Jev is, API setup, and three demos: a voice-controlled browser, AI memory, and a YouTube predictor, with chapter timestamps in the post.
Jev Media & TalksVideo#community#x#video
Community
The pg-jev author demos jev(), a PostgreSQL extension that filters table rows with natural-language conditions and no index or embeddings, judging 129 rows in about a second.
Jev Tools & CLIsVideo#community#x#video
Community
A widely read counterpoint to Jev-based context compaction: compaction is reconstruction, not filtering, and scoring tool calls to drop history misunderstands context management.
Jev Practices & PatternsPost#community#x#compaction
Community
The WebMCP benchmark author reports that Jev paired with the small Mercury 2.5 model solved 100% of tasks at roughly 112x lower model cost than GPT-6 Astra with computer use.
Jev Practices & PatternsPost#community#x#benchmark
Community
A short demo of a model router built with Jev: each request is classified by Jev and forwarded to the model judged most suitable, shown as a screen recording.
Jev Tools & CLIsVideo#community#x#video
Community
The jevmeter author runs five yes/no questions per sentence across a debate: 1,191 Jev calls, 1.18M tokens, 415 ms median latency, and $0.0497 for the full run.
Jev CookbooksVideo#community#x#video
Community
A DuckDB extension that classifies rows in CSV, Parquet, or DuckDB tables with Jev, reported at about 10 seconds for 1,000 rows and framed as more ergonomic than a bespoke classifier.
Jev Tools & CLIsPost#community#x#duckdb
Community
Cloudflare's developer account announced that Jev is available on AI Gateway, callable from Workers with typed Noul, Choice, and Score questions returning structured answers.
Jev Tools & CLIsPost#community#x#cloudflare
Community
An independent Jev-compatible public API backed by Qwen3.6-35B-A3B and SGLang radix caching, reporting 64 parallel typed-decision tasks in under a second.
Jev Repos & SDKsVideo#community#x#video
Community
End-to-end guide to a ticket-routing workflow with confidence thresholds, zero-data-retention options, and mock-based tests that need no network call.
Jev Guides & ArticlesArticle#community#vercel#tutorial
Community
Use Jev as a Braintrust judge scorer, then inspect selected answers, confidence, and probabilities alongside the scorer answer. Includes tracing for your own calls.
Jev Tools & CLIsArticle#community#evaluation#observability
Community
2GitHub stars
An agent-first CLI for System One: ask, rank, extract, verify, screen, find, and decide from the shell, with an installable agent skill. Published on PyPI.
Jev Tools & CLIs#community#cli#agent
@jev.fn compiles a Python function definition (parameters, docstring, return annotation) into a state plus typed questions, then validates the answers back into Pydantic models.
Jev Tools & CLIsDocs#community#python#decorator
Community
5GitHub stars
An unofficial Go client for the System One API: typed judgments and calibrated probabilities instead of generated text.
Jev Repos & SDKs#community#sdk#go
12GitHub stars
Community .NET SDK for the System One API: typed noul, choice, and score questions with structured, confidence-scored answers.
Jev Repos & SDKs#community#sdk#csharp
A community PHP and Laravel SDK for the Jev model series, wrapping typed questions and probability answers for the PHP ecosystem.
Jev Repos & SDKs#community#sdk#php
6GitHub stars
Eight minimal, zero-dependency examples applying Jev to mechanical and electrical engineering: CAD/CAE/CAM routing, FEM result triage, DFM screening, and BOM alignment.
Jev Repos & SDKs#community#engineering#python
A community playground with over a hundred use cases, games, and model challenges, with editable prompts and side-by-side comparisons.
Jev Tools & CLIsPlayground#community#playground#nextjs
406GitHub stars
A monorepo of roughly 20 latency-focused demos: moderation firehoses, rerankers, inbox triage, macOS launchers, and closed-loop control simulators, each with p50/p95 telemetry.
Jev Repos & SDKs#community#demos#typescript
3kGitHub stars
One AI trade decision every Monad block: Jev evaluates the market state and returns a typed decision the bot acts on, on Kuru's MON-USDC market.
Jev Repos & SDKs#community#trading#realtime
1.4kGitHub stars
Train a small model that chooses among a changing list of text options, one probability per option in a single pass. Includes Doom, chess, and Wikispeedia demos.
Jev Repos & SDKs#community#training#research
Run a Pydantic AI agent on Jev: each field of the output type becomes one question, the prompt is the state, and confidence comes back per field.
Jev Tools & CLIsDocs#community#pydantic#python
Community
A practical tour with JavaScript examples: typed choices, scores, probabilities, real latencies and costs, the jagged edges, and how to split jobs correctly.
Jev Guides & ArticlesArticle#community#tutorial#javascript
Community
Give Jev a screen snapshot and a task, and it chooses the next action for agent-driven mobile QA. Ships as a CLI you can point at a real app.
Jev Guides & ArticlesArticle#community#mobile#qa
Community
64GitHub stars
An MCP server that puts Jev in the coding loop for Cursor, Codex, and other MCP clients: coding-loop checks, ranking, verification, and review tools.
Jev Tools & CLIs#community#mcp#coding-agent
An open Python toolkit with question builders, confidence gates, tiered routing, a concurrent corpus evaluator, calibration tooling, a CLI, and an MCP server, with published benchmarks.
Jev Repos & SDKsArticle#community#python#mcp
Community
32GitHub stars
Jev-backed auto mode for the Pi coding agent: semantically approves bash, write, and edit tool calls, and fails closed whenever a decision cannot be made.
Jev Tools & CLIs#community#coding-agent#permissions
The launch story: why TypeSafe built decision models, the side-by-side demo, the Doom and Wikiracing bots, and the published workflow evals.
Jev Guides & ArticlesArticle#official#announcement#benchmarks
Official
AI Gateway's evaluation modality: call Jev as `typesafe-ai/jev` through the AI SDK's experimental_evaluate API, with structured answers instead of free-form text.
Jev Tools & CLIsDocs#community#vercel#integration
Community
Model card for `typesafe-ai/jev`: evaluation type, $0.042 per 1M input tokens, zero output token charge, and a hosted playground.
Jev Tools & CLIs#community#vercel#pricing
Community
Access Jev through OpenRouter's decisions endpoint, an alternative route to early access that still uses TypeSafe's question and answer shapes.
Jev Tools & CLIs#community#openrouter#api
Community
The canonical introduction: Jev is TypeSafe's flagship model and the first System One model. Send state and typed questions, get structured answers your code can use directly.
Jev Guides & ArticlesDocs#docs#official#primitives
Official
Everything you need to make your first request: install an SDK, get an API key, and send state plus typed questions.
Jev Guides & ArticlesDocs#docs#official#quickstart
Official
The three TypeSafe question types, the typed answers they return, how to choose between them, and how to ask several in a single call.
Jev Practices & PatternsDocs#official#primitives#choice
Official
How TypeSafe reports certainty, how it differs from probability, and how to use it architecturally to gate and route decisions.
Jev Practices & PatternsDocs#official#confidence#routing
Official
Architectural patterns for System One systems: speculative fan-out, confidence-gated routing, composite scoring, and intent routing.
Jev Practices & PatternsDocs#official#patterns#architecture
Official
Design AI-powered software by keeping code in control and giving System One narrow, structured decisions to make.
Jev Practices & PatternsDocs#official#patterns#architecture
Official
Explore TypeSafe use cases by industry and turn promising ideas into concrete software workflows.
Jev Practices & PatternsDocs#official#use-cases
Official
A 13-question regulatory briefing that shows batching every question into one call is 12.2x cheaper and 10x faster with no change in answers.
Jev CookbooksDocs#official#cookbook#batching
Official
One question per query-candidate pair raises top-1 accuracy from 5% to 18% and top-10 accuracy from 38% to 62% on 40 CLERC legal queries.
Jev CookbooksDocs#official#cookbook#reranking
Official
Screen every message going into and out of an LLM app: a Noul describes possible hazards, a Score rates severity, and code thresholds the probabilities.
Jev CookbooksDocs#official#cookbook#guardrails
Official
Classify documents through deep patent, retail product, biomedical, and source-code hierarchies using parallel beam search over Choice probabilities.
Jev CookbooksDocs#official#cookbook#classification
Official
Classify SEC annual reports into 75 industry groups with one Choice each, then read confidence to decide when to fall back to a broader division.
Jev CookbooksDocs#official#cookbook#classification
Official
A smart home assistant that uses TypeSafe to evaluate user requests, pick a tool, and fill its arguments from plain language.
Jev CookbooksDocs#official#demo#tool-calling
Official
2.7kGitHub stars
Drop-in skill for Claude Code, Codex, and other agent environments that teaches the right way to structure states and questions.
Jev Tools & CLIsDocs#official#agent#skill
Official TypeScript/JavaScript client with inferred answer types, retries, and a question DSL. `npm install @typesafe-ai/sdk`.
Jev Repos & SDKs#official#sdk#typescript
298GitHub stars
Official sync and async Python client for the TypeSafe API with typed questions, retry policies, and inferred answers. `pip install typesafe-sdk`.
Jev Repos & SDKs#official#sdk#python
Official drop-in TypeSafeClient replacement backed by OpenAI, Anthropic, and compatible LLM APIs, for comparing Jev against chat models on the same questions.
Jev Repos & SDKs#official#adapter#python

Start here with the Jev AI model

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

The Jev Day release post: Jev 1.14.0 under jev-preview plus three danger-zone features — composable images on both models, the box question type on 1.14 only, and opt-in 262k context.
Jev Guides & ArticlesArticle#official#release#vision
Official
The box question type: one bounding box per question, returned as four edges that are fractions of the image, plus confidence, with no criteria field and no not-found value.
Jev Practices & PatternsDocs#official#docs#vision
Official
LiteLLM's Day 0 post for TypeSafe Jev 1.14: the proxy adds box questions, image input and long-context mode on both POST /v1/systemone and POST /v1/decisions, forwarding TypeSafe-Danger-Zone headers only to TypeSafe deployments.
Jev Integrations & AdaptersArticle#community#litellm#gateway
Community

From the Jev community

Watch walkthroughs, read the threads, and see what builders are posting.

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.

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 reviewed 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 the Jev AI model?

Jev is TypeSafe AI's first System One model — an AI model that 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. 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 reviewed, 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 3889 entries from 293 source sites, last updated Nov 4, 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. 3889 of the 3889 entries carry one today.

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