Structured Output
Structured output constrains a model to return data in a specified machine-readable format, such as JSON matching a schema, rather than free-form prose. This makes responses reliably parseable by downstream code and is essential for function calling, data extraction, and integrating models into software pipelines.
Definition
Structured OutputApplications often need a model's answer as data, not paragraphs. Structured output enforces a target shape — commonly JSON conforming to a provided schema — so the response can be validated and consumed programmatically without brittle text parsing. Providers offer modes that guarantee syntactically valid, schema-conformant output.
Structured output underpins function calling and tool use, where arguments must match a declared schema, and it powers reliable extraction and classification tasks. It shifts effort from cleaning up model text to defining the schema, and pairs naturally with validation as a guardrail.
Frequently asked questions
What is Structured Output?
Structured output constrains a model to return data in a specified machine-readable format, such as JSON matching a schema, rather than free-form prose. This makes responses reliably parseable by downstream code and is essential for function calling, data extraction, and integrating models into software pipelines.
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