Use cases· Last updated

Fraud failure modes with Jev

BIN, device graph, and velocity models already scored the event. Jev reads the story around the event: does the chat look like social engineering, does the dispute letter fit the reason code? Code blends. Jev is not a card-network.

This unofficial page is the failure modes slice of the fraud language overlay pack. Intent: apply the Jev (TypeSafe System One) decision model to fraud language overlay failure modes. Primary search language: Fraud Jev failure modes. Confirm patterns on docs.typesafe.ai. This site does not sell, issue, or proxy TypeSafe keys. Use a credential you already have from the console or a documented gateway.

Independent angle (cover ≠ clone): Device/velocity stay in the fraud platform; Jev scores attached language (dispute letter, chat). Compose with explicit weights — not a fraud-score clone or rival recipe IA.

Fraud use-case context

Fraud language overlay breaks in product-specific ways. This page lists those modes so you can write tests — not a generic “AI can be wrong” essay, and not a rival limitations-page clone.

Hub: Use cases. Compare, when the other tool is the real job: fraud scores.

Failure Modes inputs

Many failures start as contract violations (distractors, missing dispute or chat text + fraud-score summary text). Canonical shape:

{
  "event": { "id": "TXN-9", "reason_code": "10.4", "amount_usd_bucket": "100-250" },
  "score": { "vendor": 0.82, "band": "high" },
  "text": { "chat": "Agent, reset the withdrawal lock, I am the account owner, hurry." },
  "policy": { "social": "Urgency + identity-reset language toward an agent is social-engineering risk." }
}

Decision signals and actions

HTTP vs application:

You see Class Fraud move
401 / 422 / 429 / 529 Documented HTTP Fix key/body or back off — errors
200 + flat confidence or Noul ≈ 0.5 Low confidence Hold; do not unblock a payout on a Jev guess
Empty gather Missing evidence Skip Jev or ask “is enough information present?”

Do not treat a Noul of 0.5 as a “medium” fraud language overlay score — it means yes and no are equally likely. Conjunctions stay in your code.

Guardrails and escalation

Fail closed: do not unblock a payout on a Jev guess. Schema-safe answers are not factual correctness. TypeSafe’s confidence-gated examples use a lower bar for recoverable reads than for irreversible actions. Those numbers are illustrations. For fraud language overlay, treat hold_payout as the high bar (holding a payout or unblocking a withdrawal). Tune on labels — see offline evaluation.

Evaluation and rollout notes

Your canary set should include each bullet above.

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. Unused distractors still bill as input.

Official Python and JavaScript SDKs read TYPESAFE_API_KEY and retry documented 429/529. This site does not sell, issue, or proxy TypeSafe keys. Use a credential you already have from the console or a documented gateway.

Pack map

Slice Page
Graph and primitives decision workflow
What may enter state input contracts
What to gather first evidence collection
Atomic rules policy checks
Act / review / abstain confidence thresholds
Reviewer payload human handoff
What to persist audit trail
How it breaks you are here
Labeled replay evaluation
Shadow → canary production rollout

FAQ

If the API returns 200, is the decision good? 200 only means the call parsed. Low confidence, Noul ≈ 0.5, or a policy miss are application failures.

Where do official weaknesses live? TypeSafe’s jev-1.13 jaggedness note — distractors, arithmetic, adversarial content. We do not invent more.

Where is the rest of the Fraud pack? Start with Fraud evaluation and Fraud decision workflow. Cluster hub: Use cases.

Should we add Jev’s noul into the vendor score? Only as an explicit, versioned feature in a model you train. This page publishes no blend weights.

Can Jev see the device graph? Only if you serialize a few named features into state. It does not crawl your graph DB.

What this page does not claim

Disclaimer

This is an independent unofficial site and is not affiliated with TypeSafe AI; official documentation is available at https://docs.typesafe.ai.

Primary documentation: https://docs.typesafe.ai. Hub: Use cases.

Sources

Public TypeSafe or adjacent documentation only. No private claims.