Jev is a model for making choices. You can use it to select the next action, locate UI elements, and evaluate whether a condition holds. It is fast and inexpensive, but is not suitable for tasks that require complex reasoning.
Midscene support for Jev is experimental.
First configure a general-purpose default model (MIDSCENE_MODEL_*) and keep that configuration, then add the Jev configuration below. Jev handles Planning, Locate, and Insight; the general-purpose default model still handles tasks Jev cannot perform. See Multiple models for default model configuration.
Copy the following configuration to use Jev for Planning, Locate, and Insight:
# Planning
MIDSCENE_PLANNING_MODEL_BASE_URL="https://api.typesafe.ai/v1" # TypeSafe official API endpoint
MIDSCENE_PLANNING_MODEL_API_KEY="......"
MIDSCENE_PLANNING_MODEL_NAME="jev-1.14.0"
MIDSCENE_PLANNING_MODEL_FAMILY="jev"
# Locate
MIDSCENE_LOCATE_MODEL_BASE_URL="https://api.typesafe.ai/v1" # TypeSafe official API endpoint
MIDSCENE_LOCATE_MODEL_API_KEY="......"
MIDSCENE_LOCATE_MODEL_NAME="jev-1.14.0"
MIDSCENE_LOCATE_MODEL_FAMILY="jev"
# Insight
MIDSCENE_INSIGHT_MODEL_BASE_URL="https://api.typesafe.ai/v1" # TypeSafe official API endpoint
MIDSCENE_INSIGHT_MODEL_API_KEY="......"
MIDSCENE_INSIGHT_MODEL_NAME="jev-1.14.0"
MIDSCENE_INSIGHT_MODEL_FAMILY="jev"
When the corresponding model role is configured to use Jev, tasks are handled as follows:
- Locate: Jev performs element localization.
- Insight: Jev evaluates
aiBoolean, aiAssert, and aiWaitFor. The general-purpose default model handles aiQuery, aiString, aiNumber, and aiAsk.
- Planning: In
aiAct, Jev plans simple actions such as clicking, double-clicking, and going back. The default model plans complex actions such as input and scrolling.
Model selection is based on the capabilities required by each task. Failed Jev requests do not automatically switch to the default model.
Jev uses TypeSafe's System One protocol, not an OpenAI protocol. Some OpenAI model settings do not apply, such as temperature, native reasoning, response format, and streaming output.
Notes
- Base URL: The Base URL must include
/v1, for example https://api.typesafe.ai/v1.
- Image input limits: The latest version of Jev currently limits the longest edge of an image to 1568 pixels. Use the Agent's
screenshotShrinkFactor option to control screenshot dimensions. To avoid image quality degradation from repeated resizing and accommodate image dimension requirements in future Jev versions, Midscene does not automatically resize images to match the limits of a specific Jev version.