Jev

Jev is TypeSafe AI's decision model for software automation, returning typed decisions with calibrated confidence instead of text.

Jev is the first public System One Model from TypeSafe AI, a San Francisco lab that spent two years in stealth. Instead of producing text for people, it answers structured questions with typed decisions that software can act on, and every decision includes a calibrated estimate of how confident the model is. Developers set thresholds for when software acts on its own and when it asks a person to review, then combine decisions in code to build larger workflows. The model is trained with a method the company calls Reinforcement Learning for Calibrated Decisions, and TypeSafe reports a sample workflow running 193 times faster and 444 times cheaper than with an LLM. Input is priced at $42 per billion tokens, and Jev is in early access.

Jev at a glance

Best for: Software engineer, Founder
Runs on: API
Pricing: $42 per billion input tokens; early access
Released: September 2026
Category: AI coding tool
Website: typesafe.ai

Key features

Typed decisions instead of free text
Calibrated confidence with every answer
Thresholds for acting alone or escalating to review
Decisions combined in code into larger workflows
Low latency for high-volume automation
API access during early access

Use it for

Classify and route support tickets automatically
Approve or flag records in a data pipeline
Decide when an automation should ask a human

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