jev-spec

# jev-spec

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<p align="center"><img src="./assets/hero.png" alt="jev-spec: catch spec drift on every commit" width="100%" /></p>

🌐 [日本語](README.ja.md) | [简体中文](README.zh.md) | [한국어](README.ko.md)

**Catch spec drift on every commit.** `jev-spec` checks your code against the requirements in your Markdown specification and fails the build when they drift apart. It asks [TypeSafe AI's Jev model](https://docs.typesafe.ai) one focused question per requirement, gets a probability back, and compares it with a threshold you set. That makes it small enough for a pre-commit hook and strict enough for a CI gate.

```text
$ npx jev-spec check

=== jev-spec Check Report ===

Target: auth [✖ FAILED]
  Spec files: docs/specs/auth.md
  Code files: src/auth/session.ts
  Model: jev-1.13.0
    ✔ REQ-AUTH-01: probability: 0.97
    ✖ REQ-AUTH-02: probability: 0.08
       └─ Violation: Probability 0.08 is below minimum threshold 0.85
    ✔ introducesUnspecifiedBehavior: probability: 0.03

Overall: ✖ CHECKS FAILED

$ echo $?
1
```

*Example report. The layout is what the CLI prints (timing and cost lines omitted); the probabilities are illustrative.*

`jev-spec` is an independent open-source project. It is not affiliated with or endorsed by TypeSafe AI. Please report problems with `jev-spec` in [this repository](https://github.com/nozomi-koborinai/jev-spec/issues), not to TypeSafe.

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## Why jev-spec?

Linters and schema checks can tell you that `REQ-AUTH-02` exists, is well formed and is linked from the right place. They cannot tell you whether the code does what `RE