Jev 1.13 jaggedness
TypeSafe publishes a jaggedness page for jev-1.13 (last reviewed 2026-09-17). The model is “fast, calibrated, and good at common-sense judgment” and weaker on indirection, literal about wording, and bad at numeric precision.
This page is a pointer, not a restatement of their worked counters. Official table and examples stay on docs.typesafe.ai/model-jaggedness/jev-1.13. Unofficial; not affiliated; no keys.
Pin jev-1.13.0 (the versioned id) after you fit thresholds. jev-latest and the marketing line jev-1.13 can move. Log the response model. TypeSafe’s published list price for jev-1.13 is $0.042 per million input tokens (vendor claim — confirm on the models page); output tokens are free on that same page.
Failure modes they list
- Literal reading — answers the words you wrote, not the intent. Put the exact condition in
instructions; put boundaries in criteria. - Math and numbers — not a calculator. Count in code. Semantic color names beat hex. Do not reconstruct a physical quantity from a Score expectation.
- Date and time — dates are text, not ordered quantities. Extract parts (Choice over months/days); compare in code. See the date-extraction cookbook.
- Indirection — double negatives and multi-hop properties cost accuracy. Name the field.
- Large irrelevant state — distractors hurt. Filter first.
- Adversarial content — state is not treated as hostile by default. Injected instructions can move answers. Test.
- Contradictory instructions vs criteria — align them.
- Structural invariants — Noul and yes/no Choice need not match; a question and its negation need not sum to 1. Ask once, directly.
- Generation — do not chain Choices to write text.
They want reports of new modes on Discord.
Design rules we keep repeating because they do
- Ask something code cannot compute exactly.
- One judgment per question.
- Avoid System Two piles of hops.
- Do not dump the whole warehouse into
state.
Ask Jev vs do it in code
| Task | Owner |
|---|---|
| Common-sense on a short language packet | Jev Choice / Score / Noul |
| Arithmetic, counts, “which amount is larger” | Code |
| Date order, business-day math | Extract parts; compare in code |
| Write the email / footnote / graph schema | LLM or human — not Jev |
| Walk a multi-hop property | Graph/SQL first; then one atomic question |
The official page explains why each mode fails; this table is only the ownership rule.
When not to use Jev
Do not use Jev as a calculator, a date library, or a writer. If the answer is a join, a regex, or a > b, official “how to build” keeps that in code.
Do not use Jev to paper over a bloated state. Distractors are a billed accuracy tax: unused tokens still count as input at the vendor list price above.
Do not assume a yes/no Choice and a Noul on the same proposition will agree, or that P(A) + P(not A) = 1. Enforce identities in code if you need them.
This pointer is not a substitute for the official modes page. We will not clone their paragraphs or invent extra modes.
When the official modes page wins
Read TypeSafe’s note for worked counters, the review date, or to file a new mode. This URL is the index; that URL is the source. See Jev 1.13 explainer and atomic questions.
Production sketch
- Before a new question ships, classify it: language snap vs exact compute vs generation.
- Exact compute and generation leave the Jev call. Language snaps get one question, named fields, filtered state.
- Pin
jev-1.13.0. Fit floors on a labeled set that includes math/date distractors and one adversarial span. - In the worker, compare numbers and dates in code; pass only the residual language into
state. - Log
response.model, the git SHA of criteria, and whether a human overrode. Replay after any alias move.
Hub: Comparisons. Siblings: why Jev gives up generation, Noul primitive.
FAQ
Is jaggedness a Jev-vs-product bake-off?
No. It is TypeSafe’s own list of jev-1.13 weaknesses. We point; we do not invent benches.
Does pinning jev-1.13.0 remove jaggedness?
No. Pinning stops silent mode drift. Math, dates, and generation stay weak until you keep them in code.
Can I ask Jev which of two dates is later?
Extract the calendar parts (or unix timestamps) in code. Dates in state are text, not ordered quantities.
Schema-safe means true? No. A well-typed wrong answer is still wrong.
Disclaimer
This is an independent unofficial site and is not affiliated with TypeSafe AI; official documentation is available at https://docs.typesafe.ai. Never treat jev.pro as TypeSafe official documentation. We do not sell, issue, or proxy API keys.