{"slug": "typesafe-ai-s-jev-now-available-on-ai-gateway", "title": "TypeSafe AI's Jev now available on AI Gateway", "summary": "TypeSafe AI's Jev, a probabilistic decision model that returns typed Choice, Score, and Boolean answers instead of generated text, is now available on Vercel's AI Gateway and accessible through the experimental `evaluate` API in AI SDK 7.0.105 and later. TypeSafe reports Jev was up to 193.6x faster and 444.6x cheaper than LLMs on its workflow evaluations, with use cases including tool or subagent selection in agent loops, retry-or-stop decisions, urgency and risk scoring, and output verification. Jev supports Zero Data Retention and No Training per request, and its evaluation calls appear in Gateway logs, count toward budgets, and expose separate Choice and Score confidence in `result.providerMetadata.typesafe.confidence`.", "body_md": "[Jev from TypeSafe AI](https://vercel.com/ai-gateway/models/jev) is now available on AI Gateway.\n\nJev is a probabilistic decision model for software: state goes in, typed Choice, Score, and Boolean answers come out.\n\nRegular language models generate text one token at a time, which the application then parses and validates. Jev evaluates all declared questions in parallel and returns typed answers plus probabilities directly. That removes unnecessary text generation and makes it straightforward to automate clear cases while routing uncertain ones to review.\n\nTypeSafe reports Jev was up to 193.6x faster and 444.6x cheaper than LLMs on its workflow evaluations. Example use cases include:\n\nChoosing the next tool or subagent in an agent loop\n\nDeciding whether to continue, retry, ask the user, or stop\n\nScoring urgency or risk before an action\n\nVerifying model outputs and enforcing guardrails.\n\nAI SDK 7 exposes Jev through the experimental `evaluate` [API](https://ai-sdk.dev/docs/ai-sdk-core/evaluation). Choice selects an option, Score grades an ordered rubric, and Boolean estimates the probability of `true`. Install the current AI SDK (AI SDK 7.0.105 onwards supports the `evaluate` API):\n\nEach evaluation specifies:\n\n`model`: the evaluation model to call,\n\n`state`: the shared string, object, or array to evaluate, and\n\n`questions`: a map of named decisions to make about that state.\n\nCall the model with `typesafe-ai/jev`. This example turns one support case into a queue, priority, and refund-review decision, with uncertain routing sent for manual review:\n\nThe result preserves question IDs and Choice keys. TypeSafe reports separate Choice and Score confidence in `result.providerMetadata.typesafe.confidence`. Calibrate probabilities and confidence against labeled examples from your workflow.\n\nJev supports [Zero Data Retention](https://vercel.com/docs/ai-gateway/security-and-compliance/zdr) and [No Training](https://vercel.com/docs/ai-gateway/security-and-compliance/disallow-prompt-training), enabled per request in the example. Evaluation calls also appear in [logs](https://vercel.com/docs/ai-gateway/observability-and-spend/logs) and [custom reporting](https://vercel.com/docs/ai-gateway/observability-and-spend/custom-reporting), count toward [budgets](https://vercel.com/docs/ai-gateway/observability-and-spend/budgets), and accept other Gateway provider options in the same `providerOptions.gateway` object.\n\nRead the documentation on [evaluation models](https://vercel.com/docs/ai-gateway/modalities/evaluation) on AI Gateway for more details.", "url": "https://wpnews.pro/news/typesafe-ai-s-jev-now-available-on-ai-gateway", "canonical_source": "https://vercel.com/changelog/typesafe-ai-jev-now-available-on-ai-gateway", "published_at": "2026-09-16 00:00:00+00:00", "updated_at": "2026-09-17 00:24:48.629400+00:00", "lang": "en", "topics": ["ai-agents", "ai-tools", "ai-products", "developer-tools", "ai-infrastructure"], "entities": ["TypeSafe AI", "Jev", "Vercel", "AI Gateway", "AI SDK 7", "evaluate API"], "alternates": {"html": "https://wpnews.pro/news/typesafe-ai-s-jev-now-available-on-ai-gateway", "markdown": "https://wpnews.pro/news/typesafe-ai-s-jev-now-available-on-ai-gateway.md", "text": "https://wpnews.pro/news/typesafe-ai-s-jev-now-available-on-ai-gateway.txt", "jsonld": "https://wpnews.pro/news/typesafe-ai-s-jev-now-available-on-ai-gateway.jsonld"}}