Structured Output

Generate typed, constrained output using GenerationSchema. The model's response is guided to match your schema exactly.

Defining a Schema

import { GenerationSchema, GenerationGuide } from "tsfm-sdk";

const schema = new GenerationSchema("Person", "A person profile")
  .property("name", "string", { description: "Full name" })
  .property("age", "integer", {
    description: "Age in years",
    guides: [GenerationGuide.range(0, 120)],
  })
  .property("tags", "array", {
    guides: [GenerationGuide.maxItems(5)],
    optional: true,
  });

Property Types

"string" | "integer" | "number" | "boolean" | "array" | "object"

Generation Guides

Guides constrain the model's output for a property:

Method	Constrains
GenerationGuide.anyOf(["a", "b"])	Enumerated string values
GenerationGuide.constant("fixed")	Exact string value
GenerationGuide.range(min, max)	Numeric range (inclusive)
GenerationGuide.minimum(n)	Numeric lower bound
GenerationGuide.maximum(n)	Numeric upper bound
GenerationGuide.regex(pattern)	String pattern
GenerationGuide.count(n)	Exact array length
GenerationGuide.minItems(n)	Minimum array length
GenerationGuide.maxItems(n)	Maximum array length
GenerationGuide.element(guide)	Applies a guide to array elements

Generating Structured Output

const session = new LanguageModelSession();
const content = await session.respondWithSchema("Describe a software engineer", schema);

Extracting Values

Use content.value<T>(key) to extract typed values:

const name = content.value<string>("name");
const age = content.value<number>("age");

Full Example

interface Cat {
  name: string;
  age: number;
  breed: string;
}

const schema = new GenerationSchema("Cat", "A rescue cat")
  .property("name", "string", { description: "The cat's name" })
  .property("age", "integer", {
    description: "Age in years",
    guides: [GenerationGuide.range(0, 20)],
  })
  .property("breed", "string", { description: "The cat's breed" });

const content = await session.respondWithSchema("Generate a rescue cat", schema);

const cat: Cat = {
  name: content.value("name"),
  age: content.value("age"),
  breed: content.value("breed"),
};