Model routing

Let Jev pick which model should handle a request.

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The decisions Jev makes

In a single call, Jev evaluates each of these — in parallel, against the same input:

scorecomplexity

How complex is this request?

rates it on an ordered scale:

trivial
simple
moderate
hard
very hard / architectural

choiceroute

Which model should handle it?

picks one of these options:

fast — fast cheap model — trivial edits, formatting, lookups
balanced — mid model — normal features and fixes
strong — frontier model — architecture, migrations, hard reasoning

noulneeds_tools

Will this likely require tool calls (reading files, running commands)?

returns a calibrated yes/no probability.

The exact request

This is the real payload behind the live demo — copy it, change the state, and you're building:

{
  "model": "jev-latest",
  "state": "Incoming user request to an AI coding agent: \"Refactor our auth service to support multi-tenant SSO with SAML and SCIM, keep backward compatibility, and write a migration plan.\" Available models: fast (cheap, small), balanced (mid), strong (expensive, frontier).",
  "questions": {
    "complexity": {
      "type": "score",
      "instructions": "How complex is this request?",
      "criteria": [
        "trivial",
        "simple",
        "moderate",
        "hard",
        "very hard / architectural"
      ]
    },
    "route": {
      "type": "choice",
      "instructions": "Which model should handle it?",
      "criteria": {
        "fast": "fast cheap model — trivial edits, formatting, lookups",
        "balanced": "mid model — normal features and fixes",
        "strong": "frontier model — architecture, migrations, hard reasoning"
      }
    },
    "needs_tools": {
      "type": "noul",
      "instructions": "Will this likely require tool calls (reading files, running commands)?"
    }
  }
}

Wire it into your code

Read the typed answers and branch in plain code — no parsing. Auto-handle the high-confidence cases and route the uncertain ones to a bigger model or a human. It's one API call and output is free, so ask every question you need at once.

Build your own

Every scenario above is a single API call. Try any of them free in the playground, then get a hosted key to ship it — no waitlist.

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