Jev API content types
Content types for Jev are simple: the documented evaluation call sets Content-Type: application/json and a JSON body. Models are text only — string, object, or array of text values.
This page is for builders who searched an extra “endpoint” name while wiring Jev / System One. jev.pro is an independent unofficial field guide — not affiliated with TypeSafe AI. We do not sell or issue keys. Confirm first-party routes on docs.typesafe.ai/api.
The public API reference documents one evaluation route — POST https://api.typesafe.ai/v1/systemone — plus GET /v1/models. This title is not a separate first-party URL in that reference. There is no /v1/content-types. The header belongs on the official POST.
Steps
- Send JSON. Do not invent multipart, protobuf, or audio content types for System One.
- Pre-process images/audio/video into text before the call.
- Prefer named objects so instructions can address fields.
- English is the primary training language; test other languages yourself.
Request / response shape
Header: Content-Type: application/json plus Authorization: Bearer. Body: model, state, questions. Response: JSON model, answers, usage. Choice/Score answers include probabilities + confidence. Noul answers include noul only. Question ids are not sent to the model.
Official SDKs set the header for you: Python typesafe-sdk (TypeSafeClient / AsyncTypeSafeClient) and JS @typesafe-ai/sdk (systemOne on Node 20+). Raw HTTP must set it explicitly. A wrong type is a 422-class problem if the body cannot be parsed — not a reason to invent a second route.
jev-latest / jev-preview currently resolve to jev-1.13.0 — confirm. Pin when floors exist. Vendor-claimed context (64k / 32k) still counts Base64 blobs you stuffed “just in case.” Those blobs are not vision input; they are expensive text (vendor claim: $0.042 / million input tokens, output free).
When not to stretch the header
You can put XML or HTML as text inside state. The HTTP envelope is still JSON. You cannot ask System One for NDJSON token streams, Server-Sent Events, or multipart file parts. You receive a complete answers map. Documented errors: 401, 422, 429, 529. SDKs retry 429/529.
Pitfalls
application/x-www-form-urlencodedclones of chat APIs.- Base64 blobs in state “just in case.” They cost tokens and are not vision input.
- Sending
audio/mpegand hoping the model transcribes. - Assuming Gateway wrappers keep the same header names — confirm that door.
See also
- API hub — JSON evaluation POST
- Request format — required fields inside the JSON
- State — text shapes the model can use
- Language support — English primary
FAQ
Is this a documented TypeSafe URL?
The header belongs on POST /v1/systemone — there is no /v1/content-types.
NDJSON streaming?
Not how System One is documented. You get a complete answers map.
XML in, JSON out?
You can put XML text in state. The HTTP envelope is still JSON.
Can I attach a PDF part?
Not as multipart. Extract text first, then evaluate.
What this page does not claim
- Official TypeSafe status, logos, or support.
- That jev.pro sells, issues, or proxies API keys.
- Extra first-party HTTP routes beyond
POST /v1/systemoneandGET /v1/modelsunless the API reference lists them. - Invented latency SLOs, search volume, or unofficial prices. List price and rate limits are vendor claims — confirm on models.
- That a schema-constrained answer is automatically factually correct.
Disclaimer
This is an independent unofficial site and is not affiliated with TypeSafe AI; official documentation is available at https://docs.typesafe.ai. Never treat jev.pro as TypeSafe official documentation. We do not sell, issue, or proxy API keys.