Jev GUI Delegate
Windows and Chrome GUI delegation for Codex: a local controller runs a task contract, calling Jev only for semantic choices.
Overview
Jev GUI Delegate is a Chinese-language prototype that lets Codex hand GUI work on Windows and Chrome to a local controller. The main model delivers a task contract with goal, allowed actions, scope, inputs, steps and success conditions; the controller observes, matches and executes deterministically, calling Jev only when a semantic choice is needed, and verifies the actual result after each step. Chrome runs through the host's official browser session and Windows through UI Automation, without copying profiles or extracting cookies.
It saves progress and supports filling missing inputs, partial repair, pause, cancel and user takeover; uncertain results are not auto-replayed, and low confidence stops for a person. In two synthetic rounds of the same four tasks and 24 actions, the README reports the main model's tokens fell about 90 percent (from about 2.26M to about 0.19 to 0.24M including cached input) with all tasks completed and 3 to 3.5 times faster end to end, while cautioning that the sample is small and not a billing saving. Version 0.7.0 ships a Windows package.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Choice | Which on-screen control matches the next step? | — |
| Yes / no | Is this candidate action acceptable for the task? | — |
How it works
- Codex writes a task contract
- Controller observes and matches controls deterministically
- Jev resolves semantic choices; low confidence stops for a person
- Verify each result and save progress
Strengths
- Large reduction in main-model tokens in tests
- Uses official browser session and UIA
- Explicit contracts and recovery
Caveats
- Small synthetic test set
- Windows x64 focus
- Chinese documentation
Getting started
Download the 0.7.0 Windows package and follow INSTALL_ZH.md.At a glance
- Type
- Project
- Status
- prototype
- Language
- Python
- Runtime
- Windows UIA and Chrome session, Codex skill
- Has code
- yes
- Has tests
- yes
Use cases and integrations
How curated lists describe it
Windows and Chrome GUI delegation for Codex: the model hands over a task contract, a local controller runs deterministic steps, and low confidence stops for a person. Chinese.
MrJev/awesome-jev
Frequently asked questions
What does Jev decide?
Semantic control selection when deterministic matching is not enough.
How much did it save?
About 90 percent of main-model tokens on a four-task synthetic test.
Does it copy my browser cookies?
No, it uses the host's official browser session.
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