Use cases· Last updated 2026-09-21

Routing input contracts with Jev

Not every request deserves the same handler. Jev classifies cheaply; code sends work to a lookup, a specialist LLM, a costlier model, or a human.

This unofficial page is the input contracts slice of the intent and model routing pack. Intent: apply the Jev (TypeSafe System One) decision model to intent and model routing input contracts. Primary search language: Routing Jev input contracts. 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): Routing glossary + compare vs rules/queues; ranked-route floors. Not a clone of a rival intent-routing glossary page.

Routing use-case context

An input contract is the allow-list of fields you will ever POST for intent and model routing. It is a decision contract for the latest user request: if a field is not named in instructions, it should not be in state. That is how you beat noisy “dump the object” integrations — the rival-intent failure mode — without cloning anyone’s IA.

Hub: Intent routing. Compare, when the other tool is the real job: rules and queues.

Input Contracts inputs

Documented System One inputs: state (string, object, or array of text) and a questions map. English is the primary training language. Images, audio, and video are not accepted.

Allow for intent and model routing:

{
  "user": { "message": "Where is order 8831?", "locale": "en" },
  "session": { "authenticated": true, "plan": "free" },
  "catalog": { "handlers": ["order_status", "product_question", "return_exchange", "complaint", "other"] }
}

Bind paths: user.message, session.authenticated.

Refuse at the wrapper (do not send):

• full order-line JSON when the intent might be a product question
• every historical session turn
• model price tables (your code already knows those)

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.

Decision signals and actions

The contract exists so each primitive stays atomic:

If a new CRM field appears, either add a question that names it or drop it. Do not “just include it.” Do not treat a Noul of 0.5 as a “medium” intent and model routing score — it means yes and no are equally likely. Conjunctions stay in your code.

Guardrails and escalation

Contracts are a guardrail: missing required text → do not call Jev (or ask a Noul “is enough information present?”). That is cheaper than a confident wrong intent. TypeSafe’s confidence-gated examples use a lower bar for recoverable reads than for irreversible actions. Those numbers are illustrations. For intent and model routing, treat complaint_auto_llm as the high bar (opening a refund/complaint LLM path or jumping to a costly model). Tune on labels — see offline evaluation.

Evaluation and rollout notes

Version the contract (field list + criteria git SHA) next to the pinned model. Replay handler gold and whether a human would have taken the complaint when either changes. 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

FAQ

What happens if I send the whole warehouse row? jev-1.13 loses accuracy as distractors grow (official jaggedness note). Drop full order-line JSON when the intent might be a product question. 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.

Can I send images of the artifact? No. State is text (string, object, or array of text). Transcribe first.

Where is the rest of the Routing pack? Start with Routing decision workflow and Routing evidence collection. Cluster hub: Use cases.

Is intent a reserved API field? No. You name the key. See glossary: intent.

When do rules beat Jev? When the route is already in structured data. Compare traditional routing.

What this page does not claim

• No claimed win-rate versus regex routers.
• LangChain ModelRouterMiddleware APIs are LangChain’s — believe their docs if they move.
• Not official TypeSafe.
• Official TypeSafe status, or that jev.pro issues API keys.
• That a schema-constrained answer is automatically factually correct.

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.