Jev in Practice: Browser Use and Agent Workflows

The author built gpui-agent so Jev can operate GPUI app UIs much like browser use, which has worked well for agents testing their own GPUI apps; it requires gpui-pre 0.3.5 plus a patch.

In a demo app, Ear detects the language, Voz transcribes and Redact strips PII, while Jev makes about 20 decisions in one call within milliseconds to pick which on-device model to run, with no LLM in the loop.

The BYOR tool lets you choose whether Jev classifies requests by task type, complexity or your own question, then drag models into each route and compare intelligence, speed and price before saving.

The author uses Jev's fast thinking mode to decide whether to buy or sell based on an asset pair's price feed, then execute real trades.

The author built Reflex, a free tool that uses Jev to understand each link's intent and pick the right browser dynamically instead of relying on static routing rules.

The author says Jev retrieves from an LLM wiki 10x cheaper and 40x faster than a frontier model like Sonnet, and built s1m, a command-line knowledge recall tool for agents, on that basis.

Degen Village gained an NFT analyzer that uses Jev to produce typed verdicts with confidence scores, flagging a collection up 300% as nine wallets wash trading and avoiding it before the floor collapsed.

With the same model and no weight changes, having Jev ask six structured questions after each failure in 50 adversarial checkout attempts kept 8 rules and discarded 16 noisy failures, taking 29 seconds and $0.02.

An opinion post argues that calling a large model for every branch decision is wasteful, and Jev replaces it with a typed Choice plus probability, priced at $0.042 per million input tokens with 70–500 ms latency per TypeSafe.

The card game Dungeon Rummy integrated Jev to create five Jev agents as always-ready opponents, ranging from the strongest to the weakest.

OpenRouter launched a Classifiers feature that uses TypeSafe's Jev to automatically tag LLM requests, with results analyzable in Explore.

A roundup of 20 open-source tools built with Jev's decision-making, from browser agents and model routing to code review, trading market making and playing Mario.