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Adapters

TypeSafe

You have a TypeSafe API key and you want typed answers from Jev. Install @tanstack/ai-typesafe. Then pass typesafeDecider to decide().

The adapter covers evaluate only. It talks to TypeSafe over fetch. There is no TypeSafe SDK.

Installation

sh
npm i @tanstack/ai @tanstack/ai-typesafe
npm i @tanstack/ai @tanstack/ai-typesafe

Evaluate

typescript
import { decide, choice, score, boolean } from "@tanstack/ai";
import { typesafeDecider } from "@tanstack/ai-typesafe";

const ticket = {
  subject: "Charged twice for the same invoice",
  body: "Please refund the extra payment.",
};

const result = await decide({
  adapter: typesafeDecider("jev-latest"),
  state: ticket,
  questions: {
    queue: choice({
      instructions: "Which team should handle this ticket?",
      options: {
        billing: "Payments, invoices, refunds",
        tech: "Bugs, outages, integrations",
        sales: "Pricing, upgrades, new accounts",
      },
    }),
    urgency: score({
      instructions: "How urgent is this ticket?",
      levels: ["low", "medium", "high"],
    }),
    refund: boolean({
      instructions: "Is the customer asking for a refund?",
    }),
  },
});

console.log(result.queue.value);
console.log(result.queue.probability);
console.log(result.queue.confidence);
console.log(result.meta.usage);
import { decide, choice, score, boolean } from "@tanstack/ai";
import { typesafeDecider } from "@tanstack/ai-typesafe";

const ticket = {
  subject: "Charged twice for the same invoice",
  body: "Please refund the extra payment.",
};

const result = await decide({
  adapter: typesafeDecider("jev-latest"),
  state: ticket,
  questions: {
    queue: choice({
      instructions: "Which team should handle this ticket?",
      options: {
        billing: "Payments, invoices, refunds",
        tech: "Bugs, outages, integrations",
        sales: "Pricing, upgrades, new accounts",
      },
    }),
    urgency: score({
      instructions: "How urgent is this ticket?",
      levels: ["low", "medium", "high"],
    }),
    refund: boolean({
      instructions: "Is the customer asking for a refund?",
    }),
  },
});

console.log(result.queue.value);
console.log(result.queue.probability);
console.log(result.queue.confidence);
console.log(result.meta.usage);

For question helpers, the result shape, abort, and middleware, see Evaluate.

Models

ModelDescription
jev-latestCurrent stable Jev alias
jev-1.13.0Pinned Jev release

You can also pass other TypeSafe model ids as a string.

Environment Variables

The adapter reads your API key from the environment:

sh
TYPESAFE_API_KEY=your-typesafe-api-key
TYPESAFE_API_KEY=your-typesafe-api-key
VariableRequiredDescription
TYPESAFE_API_KEYYesYour TypeSafe API key

Get a key from TypeSafe.

Explicit API Keys

To pass a key directly, use createTypesafeDecider:

typescript
import { createTypesafeDecider } from "@tanstack/ai-typesafe";

const adapter = createTypesafeDecider(
  "jev-latest",
  process.env.MY_TYPESAFE_KEY!,
);
import { createTypesafeDecider } from "@tanstack/ai-typesafe";

const adapter = createTypesafeDecider(
  "jev-latest",
  process.env.MY_TYPESAFE_KEY!,
);

Behind a proxy

Route every request through a gateway with baseURL and defaultHeaders. These two option names are the same on every TanStack AI adapter.

typescript
import { createTypesafeDecider } from "@tanstack/ai-typesafe";

const adapter = createTypesafeDecider(
  "jev-latest",
  process.env.TYPESAFE_API_KEY!,
  {
    baseURL: "https://gateway.example.com/typesafe",
    defaultHeaders: {
      "cf-aig-authorization": `Bearer ${process.env.GATEWAY_TOKEN}`,
    },
  },
);
import { createTypesafeDecider } from "@tanstack/ai-typesafe";

const adapter = createTypesafeDecider(
  "jev-latest",
  process.env.TYPESAFE_API_KEY!,
  {
    baseURL: "https://gateway.example.com/typesafe",
    defaultHeaders: {
      "cf-aig-authorization": `Bearer ${process.env.GATEWAY_TOKEN}`,
    },
  },
);

baseUrl and headers are aliases of the same two options. If you set both forms, baseURL and defaultHeaders win.

API Reference

typesafeDecider(model, config?)

Creates an evaluate adapter. It reads TYPESAFE_API_KEY from the environment.

  • model: "jev-latest", "jev-1.13.0", or another TypeSafe model id
  • config.baseURL: override the API base URL (default https://api.typesafe.ai). baseUrl is an alias.
  • config.defaultHeaders: extra request headers. headers is an alias.
  • config.fetch: override fetch
  • config.timeout: request timeout in milliseconds

createTypesafeDecider(model, apiKey, config?)

Same as typesafeDecider with an explicit API key.

The adapter sends POST /v1/systemone to that base URL.

Next Steps

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