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Structured Output

Structured output is a feature that allows you to generate structured data in JSON format with a JSON schema. This is more strict than JSON mode.

To enable this mode, set responseType to json_schema.

script({
    responseType: "json_schema",
    responseSchema: {
        type: "object",
        properties: {
            name: { type: "string" },
            age: { type: "number" },
        },
        required: ["name", "age"],
    },
})

Note that there are several restrictions on the schema features supported by this mode.

  • additionalProperties: true is not supported.
  • all optional fields (e.g. not in required) will be returned and might be null

Support

This is a list of models that support structured output. This is a changing field and the list might not be up-to-date. The best way is to try it out.

  • OpenAI: supported by gpt-4o-mini, gpt-4o-2024-08-06 and later models.
  • Ollama: supported by 0.5.0 and higher

Choices

If you are looking to build a LLM-as-a-Judge and only looking for outputs in a set of words, you can also consider using choices to increase the probability of the model generating the specified words.