1. The Production Bottleneck
Agents can propose actions with real side effects. A guardrail must distinguish content classification from authorization and must make uncertain cases visible instead of silently allowing or blocking them.
2. Architecture Comparison: Without vs With Jev
Rules mixed into a generative instruction are hard to version, test and audit.
Simple string rules miss context and can block legitimate work.
A binary allow/block result gives no path for ambiguous actions.
Represent allow, confirm and block as explicit application states.
Evaluate the proposed action and relevant context before a tool runs.
The tool layer still checks identity, permissions and resource limits.
3. Execution Micro-Flow
How state flows through the bounded decision layer during live agent execution:
4. Practical Engineering Trade-offs
✓Deploy This Pattern When:
- The policy question can be expressed as bounded outcomes
- Risky actions have a human-confirmation path
- Execution services enforce their own permissions
⚠Avoid Or Re-evaluate When:
- Prompt injection and untrusted content
- Hidden external state not included in the decision
- Treating a classifier as a complete security boundary
5. Sourced Community Builds
55 ImplementationsElune Coding Agent Switch
An author demo uses Jev to route work between Claude Code and Codex and review risky tool calls.
Auto-Guard for Coding Agent Tool Calls
Jev scores a proposed tool call and the user's request before code allows, escalates or blocks execution.
pg-jev - Natural-Language Filtering in PostgreSQL
A PostgreSQL extension for filtering, ranking and classifying rows with Jev.
Two-Stage Fraud Detection Funnel (Jev + Kimi K3)
An email fraud-classification demo that sends uncertain cases from Jev to Kimi K3.
On-Device Audio Decision Pipeline (Ear + Voz + Jev)
A demo combining local audio models with a Jev decision call.
Metaview Candidate Sourcing Agents
Metaview's CTO reports using Jev across its agents to speed up candidate searches.
Exa Live Web Context for Jev
A live demo that compares Jev's typed answer with and without retrieved web evidence.
Agent Trace Observability
A TypeSafe workflow that triages completed agent runs for review, bugs, or on-call escalation.
Jev Browser
A Jev-driven browser agent exposed as an MCP server, CLI, or library.
TypeSafe Agent Skills
Official skills that teach coding agents how to design and compose TypeSafe decision workflows.
Jev MCP
Eleven typed Jev judgment tools exposed through MCP for verification, screening, routing and review.
Instant Context Compaction
A community demonstration of using Jev to score which coding-agent context should be kept, reviewed, or dropped.
Mastra Agent Guardrail Middleware
A single-file Mastra input processor that uses Jev to moderate the latest user message.
Pi-Heed Tool Call Auditor
An agent security supervisor that audits side-effecting tool calls against the user's explicit request.
Pi Context Curator
A Pi extension that asks Jev which context units remain essential before an LLM call.
DiffJury
Evaluates public PR links to provide instant safe-to-merge or review-required verdicts.
Agent Safety Monitor
A gatekeeper evaluating proposed agent actions before execution, catching attacks with near-zero false blocks.
Bouncer
A Claude Code tool-call judgment hook with deterministic hard rules and Jev for ambiguous cases.
AI slop detector
jev is INSANE.
Hide posts on X in plain language
I built a browser extension with Jev @typesafeai that can hide/collapse posts on
A filter for reply-guy comments
Pro tip: You can use Jev to remove annoying reply guy comments that X seems to a
Jev System Architect
A coding-agent skill for finding places where fuzzy semantic logic should become an explicit Jev decision boundary.
Jev Benchmark
A community benchmark project for testing Jev as a guardrail over risky agent tool calls.
Jev Vision Boundary & Limitations Breakdown
A short critical post arguing that Jev does not directly read image pixels.
Why I Couldn't Build Jev at OpenAI: Diogo Almeida
TypeSafe Co-founder & CEO Diogo Almeida explains why post-training on generative LLMs fails on agent loops and how RLCD trains System 1.
crush-monitor
Reads a WeChat thread and scores emotion, intent and reply quality.
Doomscroll Filter
Pick a niche, and Jev sorts fresh X posts into Read, Skim or Pass.
Ad creatives from filtered assets
Jev filters content and picks assets; DeepSeek and Higgsfield turn them into ads.
is-malicious
A codebase scanner that helps you not run malicious code.
Jev Anti-Spam Bot
A Telegram bot that deletes only the spam Jev is sure about.
jev-axi
A shell CLI for agents: pick, rate, check, rank, triage and guard.
jev-drone
A simulated drone that asks Jev for a judgment 2.5 times a second.
Lurk
Find and monitor Reddit threads to get cited by AI, for free.
Watching 25 customer groups on WhatsApp
Jev reads the groups and only wakes the LLM when it matters.
Filtering WIP todos by meaning
Finds the todos where revenue moved, or the work got stuck.
Natural-language search over Zillow
Thousands of listings sorted by what the site has no filter for.
Hawk or dove?
Fed press conferences scored word by word, Jev against chat models.
jevocks
A stock terminal: Valyu brings the evidence, Jev gives the status.
fedjev-bench
Does Jev hear a rate rise coming in an FOMC statement?
Clawby re-scores four dimensions every ten minutes
Technical, liquidity, sentiment and risk, re-judged on a ten-minute loop.
A stock scoring engine, on a first investment
Non-mathematical stock data, scored by Jev into a decision.
Jev-as-Policy
One-click simulation setup with Jev as the control policy.
Voice Control a Mac with Jev
Hands-free OS accessibility and tool execution driven by Jev realtime classification.
unawair v3, a rule engine after Jev
Trying Jev led to a rule-based engine with better temperature response.
Jev in embodied robot control
Where a typed decision fits next to VLA and diffusion policies.
A family-only LINE bot for the house
Lights and AC by chat, with Jev keeping the cost down.
JEV Fuse
A governed execution layer that turns Jev probabilities into deterministic policy actions.
jev-kit for Claude Code
A Claude Code kit that wires Jev into guards, sub-agent sizing, search, browsing and review.
Jev Subconscious Helper
A lightweight decision layer that filters logs, blocks risky commands and speeds up small coding-agent checks.
Jev Skills for Routing, Guardrails and Fan-out
Reusable community skills for adding Jev decisions to agent workflows.
Jev and Claude: Workflow Architecture PDF Overview
A community overview of pairing Jev decisions with a generative model.
Reconstruct an Incident Timeline with Jev
Start with a confirmed malicious event and review which related activity belongs to the same incident.
Review Data Questions and SQL Answers with Jev
Ask a SQLite question and review the generated SQL and its evidence.
Filter Your X Timeline with Jev
Choose unwanted topics and let Jev judge each post.
Label GitHub Issues and Pull Requests with Jev
Select existing repository labels from issue and pull-request evidence.