Ecosystem
Jev on GitHub
Jev's weights are not on GitHub — the model is proprietary and hosted. What is public is the client layer: TypeSafe's official SDKs and agent skill, plus a handful of community clients in other languages. This page maps what exists and how to point each at jev-api.org.
Updated
The weights are not public
Jev is a proprietary model. Its weights, parameter count, and architecture details are not published, and there is no self-host download. The same weights serve every account, and TypeSafe says customer requests are not used for training. Everything below is a way to call the hosted model, not a way to run it yourself.
Official TypeSafe projects
TypeSafe maintains the SDKs for the System One API. Both work against jev-api.org by changing only the base URL:
- typesafe-ai/typesafe-sdk-python — the Python SDK, pip install typesafe-sdk, Python 3.10+. Set TYPESAFE_BASE_URL=https://jev-api.org and a jev-api.org key.
- JavaScript SDK — npm package @typesafe-ai/sdk; create the client with apiKey and baseURL set to https://jev-api.org, or the TYPESAFE_API_KEY / TYPESAFE_BASE_URL env vars.
- typesafe-ai/skills — TypeSafe's official agent skill — install it into your coding agent so it knows the question types and request shape.
# agent skill
npx skills add typesafe-ai/skills --skill typesafe-ai
# Claude Code plugin
claude plugin marketplace add typesafe-ai/skills
claude plugin install typesafe@typesafe-aiCommunity projects
Unofficial clients and tools built around Jev. The last column shows how to point each at this site's compatible endpoint instead of api.typesafe.ai.
| Repository | Type | What it does | Point it at jev-api.org |
|---|---|---|---|
| gopinav/jev-demo | TypeScript demo, Node.js 22+ | A demo app calling Jev through the TypeScript SDK. | SDK baseURL: https://jev-api.org |
| danvega/jev-spring-boot-starter | Spring Boot 4 starter | Jev as a Spring service with properties jev.api-key, jev.base-url and jev.model. | jev.base-url=https://jev-api.org |
| dannote/jev | Elixir/OTP client, Elixir 1.18+, OTP 27+ | An Elixir client for the System One API. | base_url: "https://jev-api.org" |
| jkudish/jev-mcp | MCP server, MIT, Node.js 22+ | Twelve typed judgment tools for coding agents. | JEV_PROVIDER=compatible + JEV_API_BASE_URL=https://jev-api.org/v1/systemone |
| laguagu/jev-skills | Agent skills collection | A collection of agent skills and examples for Jev. | Skills, not a client — pair with an SDK pointed at jev-api.org |
| aaddrick/building-with-typesafe-jev | Unofficial agent skill, MIT | Guidance on question design and community patterns. | Reference material; pair with the Python guide |
All of the above are community projects, not maintained by TypeSafe or by this site. Clients that let you set the base URL and send the standard System One body should work against jev-api.org; send one test call before wiring one into production.
Where to go deeper
Two of the ecosystem entries have dedicated guides here:
FAQ
Can I download Jev's weights?
No. Jev is proprietary; its weights, parameter count and architecture are not published. The only access is hosted APIs — TypeSafe's own, gateways, or this site.
Is there an official JavaScript SDK?
Yes — the npm package @typesafe-ai/sdk. Create the client with the apiKey and baseURL options and set baseURL to https://jev-api.org to run it against this site.
Are the community clients safe to use with a jev-api.org key?
They are third-party code — read the repos before handing any of them a key. Most only need a base URL change; send one test call first.
Does Jev have an official MCP server?
TypeSafe publishes an agent skill (typesafe-ai/skills), not an MCP server. The MCP server for Jev is the community project jkudish/jev-mcp.
Send the first decision
Pick an SDK or client above, create a key, and point it at jev-api.org.