Verified against published documentation. Examples are not live API test results. Availability and provider terms can change.
What Is the Jev API?
The Jev API is TypeSafe AI’s HTTP interface for asking a decision model focused questions. A request supplies context and named questions; the result contains typed answers for your application to interpret.
Reference: Official documentation ↗
Is the Jev API Available?
Yes. TypeSafe publishes an HTTP API and a console for obtaining credentials. Documentation availability does not guarantee that every account has immediate access, quota or billing eligibility. Check those details in your account before planning a launch.
Reference: Official documentation ↗
How to Access the Jev API
Use the official TypeSafe console to obtain an API key. Store it as TYPESAFE_API_KEY in a server-side environment variable. This website does not issue keys or send requests on your behalf.
- Open the official documentation and follow its console link.
- Confirm your account can use the selected model.
- Set a spending limit and use synthetic data for the first request.
- Keep API calls on your server; never embed a secret in frontend code.
Reference: Official documentation ↗
Jev API Example
These original examples ask one bounded question about a fictional support message. The endpoint and request fields were checked against the official reference on September 24, 2026. They have not been run against a paid account. Choose a language below; no request executes in your browser.
# Bash / zsh; set TYPESAFE_API_KEY in your environment.
curl --fail-with-body --max-time 30 \
https://api.typesafe.ai/v1/systemone \
--header "Authorization: Bearer $TYPESAFE_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"model": "jev-latest",
"state": {
"message": "Could you email a copy of the invoice from the previous month?"
},
"questions": {
"needs_invoice": {
"type": "noul",
"instructions": "Does the sender ask for an invoice copy?"
}
}
}'Original example based on the official HTTP reference. Node.js 20+, Python 3.10+ or Bash cURL. No API call runs on this website.
Jev API Response
Read the result under answers.needs_invoice. For the Noul question used here, the noul field is a number from 0 to 1 representing the probability of yes. The response also reports the model and usage.
Do not convert a probability into a destructive action without a separate policy. Decide how ambiguous results should be handled, validate the returned shape, and record the model version with each evaluation. A valid type alone does not establish a correct judgment.
Reference: Official documentation ↗
Jev API Pricing
The table reports the direct provider’s published rate, not a reseller quote. Your final bill depends on input volume and current account terms. No free tier is assumed.
| Billing unit | Published rate (USD) |
|---|---|
| 1 million input tokens | $0.042 |
| 1 million output tokens | $0 |
Source: Official pricing reference · Checked 2026-09-24.
Jev API vs Traditional LLM APIs
The interface choice starts with the output your application needs. A generative model may also offer structured output; that does not make its task or behavior identical to a decision model. This is an interface comparison, not a performance ranking.
| Your requirement | Jev decision interface | Generative LLM interface |
|---|---|---|
| Draft an explanation | Use a separate generation step | Common application |
| Choose from known options | A Choice question | Possible via a structured-output feature |
| Assess a yes/no condition | A Noul question | Requires a defined output and interpretation |
| Execute a business action | Application code owns execution | Application code owns execution |
| Establish real-world accuracy | Evaluate on your task | Evaluate on your task |
Official Resources
Start with the official API reference for the complete contract. The TypeSafe GitHub organization contains developer projects; its existence is not evidence that Jev model weights are open source. All verified resource links appear below.
Frequently asked questions
What is the official Jev API endpoint?
The documented evaluation endpoint is POST https://api.typesafe.ai/v1/systemone. Check the linked official API reference before integrating.
Can I use Jev from JavaScript or Python?
Yes. You can send HTTP requests from either language. The examples above use built-in HTTP capabilities and do not depend on a Jev-specific SDK.
Does Jev return a chat response?
The documented interface returns structured answers for Choice, Score and Noul questions. Use a generative model if you need a drafted explanation or conversation.
Where do I get a Jev API key?
Use the console linked from TypeSafe’s official quick start. Account access and billing are controlled by TypeSafe, not by this directory.
Are these examples tested against a live Jev account?
No. They are original examples checked against the published contract. No API key was supplied and no paid API call was made.
Is Jev available on OpenRouter?
OpenRouter availability has not been verified in this edition. This guide does not publish a gateway model ID or endpoint without a checked provider listing.
Go straight to the source
Reviewed Sep 24, 2026. Provider documentation can change. These are primary sources, not independent performance tests.