jev

jev is a skill for Claude Code from anton-abyzov/specweave. It costs 38 tokens per session (2,565 once invoked), scanned C, original, MIT.

A selection model for questions where all possible answers can be listed ahead of time. It can choose one named option, estimate a yes-or-no statement, or place an item on an ordered scale, but it does not generate code or prose.

In plain words
What is it for?
Use it to route tasks, choose an agent or scope, check whether a command or text is acceptable, classify failures, and score risk, severity, or priority.
Why use it?
Closed-choice decisions can be handled consistently without using a larger general-purpose model for every small routing or safety judgment. It is unsuitable for questions with unknown or open-ended answers.

Skill for Claude Code

Written for Claude Code: argument-hint in frontmatter. Also seen: mentions Claude Code.

Part of the sw plugin — 11 skills, 1 agent, 2 hooks shipped together

Good fit Use it to route tasks, choose an agent or scope, check whether a command or text is acceptable, classify failures, and score risk, severity, or priority.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/anton-abyzov/specweave/jev
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add anton-abyzov/specweave --skill jev
Clone the repo
git clone --depth 1 https://github.com/anton-abyzov/specweave

Made for: Claude Code.

Or install sw, the plugin that ships this one along with the rest of its 11 skills, 1 agent, 2 hooks.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for jev

README.md
[![agentmods](https://agentmods.dev/badge/skills/anton-abyzov/specweave/jev/github.svg)](https://agentmods.dev/skills/anton-abyzov/specweave/jev)
Your own site
<a href="https://agentmods.dev/skills/anton-abyzov/specweave/jev"><img src="https://agentmods.dev/badge/skills/anton-abyzov/specweave/jev/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for jev

Your own site · 80×15
<a href="https://agentmods.dev/skills/anton-abyzov/specweave/jev"><img src="https://agentmods.dev/badge/skills/anton-abyzov/specweave/jev.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 38 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,565 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 2 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00038 $0.02565
Opus 5.5 $0.00015 $0.01026
Sonnet 5.5 $0.00008 $0.00513
Haiku 4.5 $0.00004 $0.00257

Measured 14d ago against content hash a9efb39df53c, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade C, and why

jev scanned grade C with 2 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 14d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Recursive force deletehighDestructive command

rm -rf with a variable or a broad path is one typo away from removing the wrong tree.

`specweave jev guard "rm -rf ./build"` exits 0 allow, 2 warn, 3 deny, 4 unavailable. Call it yourself before

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

not found → **manual path** (the same POST by hand; curl and PowerShell forms below).
plugins/specweave/skills-optional/jev/SKILL.md · 149 lines

How it starts

The opening of the file, as written. The whole thing — 149 lines — stays where its author put it; the contents beside it link to each section on GitHub.

sw-jev — bounded decisions

These selection models evaluate state against questions whose answers are enumerated in advance and return probabilities. Measure latency, cost and error rates on your own fixtures before enabling routing. It cannot answer outside your schema and never writes code, prose or explanations. Run specweave --version: exit 0 → CLI path; not found → manual path (the same POST by hand; curl and PowerShell forms below).

The one test

Can every possible answer be written down before the call? Yes → Jev. No → keep it in the frontier model. That is the whole rule. Three primitives: choice picks one of 2–255 named options and returns probabilities plus a confidence; noul returns the probability a statement is true (0–1), for yes/no gates; score places the state on 2–10 described, ordered levels, for graded severity or risk.

What leaves the machine

Every call sends its state — prompt text, task titles and acceptance criteria, the shell command, test-output tails, screened text, page text and element names — to the configured provider (OpenRouter, TypeSafe or OpenAI) under your own key. Secret-shaped values (tokens, --password/--token flags, KEY=value assignments, bearer headers, URL credentials) are masked heuristically first and the count is reported, but masking is best-effort, never a guarantee.

Setup

Key in the environment: OPENROUTER_API_KEY (endpoint https://openrouter.ai/api/v1/systemone, model jev-1.13) or TYPESAFE_API_KEY (https://api.typesafe.ai/v1/systemone, model jev-latest), or OPENAI_API_KEY (https://api.openai.com/v1/decisions, model gpt-6-luna). JEV_API_KEY is a fallback for all three providers. Never print, echo, log or commit the value — report the variable name only. CLI: specweave jev setup pings live, then writes jev.enabled: true into .specweave/config.json. Manual path: confirm the variable exists without printing it (grep -q OPENROUTER_API_KEY .env, PowerShell Select-String -Quiet), then set "jev": { "enabled": true } in .specweave/config.json yourself.

Read the full file on GitHub · 149 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 14d ago Changed · -2 lines · -8 tokens per session a9efb39df53c
  2. 27d ago Changed · -53 lines · +46 tokens per session scan A → C 587194b8b165
  3. 1mo ago First seen · 204 lines · 0 tokens per session scan A 0ec12b3d3542

Subscribe to this mod's changes

jev is a skill published in the GitHub repository anton-abyzov/specweave (167 stars, last pushed today), licensed MIT. It adds 38 tokens to every session and 2,565 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it C with 2 findings (recursive force delete, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-22.