LLMs can be unpredictable when you need output in specific formats. Think of asking a model to generate JSON without guidance, it might produce valid text that breaks JSON specification. **Structured Output (also known as Guided Decoding)** enables LLMs to generate outputs that follow a desired structure while preserving the non-deterministic nature of the system.
In simple terms, structured decoding gives LLMs a "template" to follow. Users provide a schema that "influences" the model output, ensuring compliance with the desired structure.