Will adding semantic rules force me to rewrite my Zod schemas?

No. semantic() wraps your existing base schema and returns the same schema type, so extend, strict, and toJSONSchema keep working and callers still use safeParseAsync plus getSemanticIssues to separate meaning issues.

What happens when Jev times out or returns something unusable?

The parse fails with an unavailable issue carrying a reason such as timeout, network, http, malformed response, not_json, or state_too_large. It never treats a missing judgment as a pass, and aborts are re-thrown rather than converted.

How do pass, rejected, and uncertain differ when I route results?

Against threshold t, p >= t passes, p <= 1-t is rejected with your message, and anything between is uncertain with your uncertainMessage. Both rejected and uncertain fail the parse; details.kind lets you auto-reject one and route the other for human review.

Can one parse check a whole array without a request per row?

Yes with semanticArray, which packs elements into as few requests as possible with a 128-question default and issue paths like [index, ...rule.path]. Each request carries only its slice, so cross-item conditions still need semantic() on the whole array.

What Zod version does zod-jev need?

zod@^4.3.0 and Node 20 or newer; it excludes zod 4.0 to 4.2 because deriving a schema in those versions silently drops refinements.

How does zod-jev treat an unavailable judgment?

It fails closed: if it cannot obtain a judgment the outcome is unavailable, reported as an issue and never silently treated as a pass, with a reason such as timeout, network, http or malformed response.

What is the default acceptance threshold in zod-jev?

0.95, configurable within the 0.5 < t <= 1 limit; a probability at or above t passes, one at or below 1 - t is rejected, and anything between is uncertain.

CommunityJev Repos & SDKs

Zod Jev

Q: Can one parse check a whole array without a request per row?

Yes with semanticArray, which packs elements into as few requests as possible with a 128-question default and issue paths like [index, ...rule.path]. Each request carries only its slice, so cross-item conditions still need semantic() on the whole array.

Q: What Zod version does zod-jev need?

zod@^4.3.0 and Node 20 or newer; it excludes zod 4.0 to 4.2 because deriving a schema in those versions silently drops refinements.

Q: How does zod-jev treat an unavailable judgment?

It fails closed: if it cannot obtain a judgment the outcome is unavailable, reported as an issue and never silently treated as a pass, with a reason such as timeout, network, http or malformed response.

Q: What is the default acceptance threshold in zod-jev?

0.95, configurable within the 0.5 < t <= 1 limit; a probability at or above t passes, one at or below 1 - t is rejected, and anything between is uncertain.

Zod 4 companion that adds Jev meaning checks to shape checks: one parseAsync call sends every semantic rule as noul questions in a single request and turns probabilities into ordinary Zod issues.

See highlights

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Stars: 8
Language: TypeScript
License: MIT
Published by: Community
Author: jomatsu
Last verified: Oct 2026

jomatsu/zod-jev

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Last pushed: Updated Sep 2026

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About this project

Zod validates the shape. Jev validates the meaning. zod-jev composes TypeSafe Jev (System One) semantic checks into Zod 4 schemas. Shape rules stay in Zod. Judgments that only a model can make ("does this body contain personal data?", "is this price plausible for this item?", "does the category match the description?") become calibrated probabilities that your code can threshold on.

Quoted from the project's README. Read the full README.

Tagscommunity jevbest catalog-import awesomejev

Works forJev for Classification

Used inJev for Software & DevTools

Languages: TypeScript

Highlights

semantic() returns the same schema type, so extend, strict, and toJSONSchema keep working.
Rules carry id, is, message, path, and threshold; probabilities map to pass, rejected, or uncertain.
Fail-closed design: unavailable judgments report an issue and never count as a pass.
Needs Node 20+, a zod 4.3 release, and TYPESAFE_API_KEY; rule IDs stay local.

Watch out

Design notes and the migration guide are written in Japanese, and Jev is an early-access hosted model billed by input tokens. Copy reviewed against the repository README on 2026-10-04, not from running it.

Questions about this entry

Short answers drawn from the linked project or page.

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jod

TypeScript layer that binds a Standard Schema state to Jev Choice, Score, and Noul questions, validating locally before sending one parallel request with typed projections.