— Developer Tools

Build Jev Schemas From Plain Language

Transform decision descriptions into valid Jev JSON for routing, classification, and guardrails. Free, no signup.

— the generator

Describe your decision

Describe the decision you want Jev to make in plain language(0/2000)
optional

Let AI decide or specify the type yourself

1 variant

Your Jev Schema Will Appear Here

Describe a decision and click Generate

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What is a Jev Question Builder?

The Jev Question Builder transforms plain-language decision descriptions into valid Jev JSON schemas. Jev is a decision model API that returns typed, probability-backed answers instead of generated text — ideal for routing, classification, moderation, and guardrails in production applications.

Describe what you want to decide in natural language, and the tool generates a complete Jev request body with properly structured instructions and criteria. Supports all three Jev question types: Choice (pick one option), Score (rate on a scale), and Noul (yes/no judgment).

Key Features

Plain Language to Structured Schema

Describe your decision in everyday language — 'route support tickets to the right team' or 'rate how urgent this message is' — and get a properly formatted Jev question with clear instructions and well-defined criteria.

All Three Jev Question Types

Generates Choice questions for classification (up to 255 options), Score questions for ordered ratings (2–10 levels), and Noul questions for yes/no judgments. Let the AI pick the best type or specify it yourself.

Best Practices Built In

The generated schema follows Jev's documented best practices: distinct descriptions for every option, 'other' catch-all for Choice questions, proper low-to-high ordering for Score levels, and affirmative phrasing for Noul.

Ready-to-Use JSON Output

Copy the complete JSON request body directly into your code. Includes the model version, sample state, and properly structured questions map — ready for the Jev API via OpenRouter.

Free for All Developers

No sign-up, no API key required. Generate as many Jev schemas as you need while building and testing your decision workflows.

Perfect for everyone

  • Developers integrating Jev into applications
  • Engineers building AI-powered routing and classification
  • Teams implementing content moderation and guardrails
  • Anyone learning the Jev API

How to Use the Jev Question Builder

Transform plain-language decisions into valid Jev JSON schemas in three simple steps

1

Describe Your Decision

Enter a plain-language description of the decision you want Jev to make. Be specific about the options, categories, or judgment criteria. For example: 'Route customer support tickets to shipping, refunds, billing, or general support based on the message content.'

  • Mention specific options or categories if you have them in mind
  • Describe what input (state) the decision will be made on
  • Include any edge cases or 'other' scenarios
2

Choose Question Type (Optional)

Let the AI automatically choose the best question type, or specify it yourself. Use Choice for classification into categories, Score for ordered ratings or severity levels, and Noul for simple yes/no judgments.

3

Generate and Copy JSON

Click generate to create a complete Jev request body. The output includes the model version, sample state, and properly structured questions with clear instructions and criteria. Copy it directly into your code.

4

Send to Jev via OpenRouter

Use the generated JSON as the request body for POST requests to OpenRouter's API with model 'typesafe/jev-1.13'. The response includes typed answers with probabilities you can use directly in your application logic.

Who Uses the Jev Question Builder?

Build Jev decision schemas for routing, classification, moderation, and more

Support Ticket Routing

Automatically route incoming support tickets to the right team. Generate Choice questions that classify messages into shipping, billing, refunds, technical support, or other categories based on the ticket content.

  • Route tickets to specialized teams instantly
  • Include an 'other' catch-all for edge cases
  • Get probability-backed confidence for each routing decision

Survey Response Coding

Analyze open-ended survey responses at scale. Create Noul questions for each theme in your codebook to tag responses with multiple categories, then aggregate the results for reporting.

  • Code thousands of responses in minutes
  • Multi-tag with one yes/no question per theme
  • Validate against hand-coded samples

Content Moderation and Guardrails

Build moderation pipelines that flag content based on specific criteria. Use Score questions for severity ratings or Noul questions for policy violation checks, with thresholds you control.

  • Set confidence thresholds for automated actions
  • Combine multiple checks in a single request
  • Keep humans in the loop for borderline cases

Intent Classification

Classify user intents in chatbots and voice assistants. Generate Choice questions that map user messages to predefined intents, with probabilities that help you handle ambiguous inputs.

  • Map messages to intents with confidence scores
  • Handle 'none of the above' with an other option
  • Use probabilities to trigger clarification flows

Tips for Best Results

Write better Jev questions with these best practices from the official documentation

Tip 01

State the Exact Condition

Jev answers the question you wrote, not the one you meant. Be specific in your instructions. When you look at a wrong answer and find yourself explaining what you really meant, that explanation is the missing half of the instruction.

Tip 02

Keep Arithmetic in Code

Jev is not a calculator. Don't ask it to count items, sum values, or compare dates. Extract the semantic judgment with Jev, then do the math in your application code.

Tip 03

Use Distinct Option Descriptions

Every Choice option needs a clear, unique description that tells Jev when to select it. Overlapping or vague descriptions lead to inconsistent results. Include boundary cases in the criteria.

Tip 04

Phrase Noul for Affirmative = High

Write Noul instructions so that a high probability (near 1) means 'yes' and low (near 0) means 'no'. Inverted phrasing confuses the model and hurts accuracy.

Tip 05

Send Only Relevant State

Large states full of irrelevant detail act as distractors. Filter your input to include only what the decision needs. You also pay per input token, so trimming saves money.

Tip 06

Test with Reordered Options

Jev can lean toward the first option in a Choice. Reorder your options and verify the answer is consistent. If it changes, your descriptions need more clarity.

Frequently Asked Questions