With structured output, the AI answers in a fixed format, such as a table or JSON, so a program can process the answer directly.
Example
From an invoice, the AI reads the date, amount and sender and always returns them in the same three fields.
For pros
APIs let you set a JSON schema the model must follow. That is more reliable than asking in the prompt. The content can still be wrong: the schema secures the format, not the facts.
