Drex v1.5

const res = await fetch("https://openrouter.ai/api/alpha/decisions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.OPENROUTER_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "nace-ai/drex-v1.5",
    "state": {
      "ticket": "I was charged twice this month."
    },
    "questions": {
      "needs_human": {
        "type": "noul",
        "instructions": "Does this ticket need a human?"
      }
    }
  }),
});
if (!res.ok) throw new Error(`Decisions ${res.status}: ${await res.text()}`);
const { answers } = await res.json();
// A noul answer is the probability of "yes". Your code picks the thresholds.
const p = answers.needs_human.noul;
if (p >= 0.9) console.log("yes");
else if (p <= 0.1) console.log("no");
else console.log("send to a human", p);

Decisions is an alpha endpoint on OpenRouter. The TypeScript SDK exposes it as openRouter.alpha.decisions.create().