Structured Output

Layer 2 · Mechanics

Structured Output

The mechanics: schema-guided generation, validation-and-retry loops, and how constrained decoding actually enforces validity.

8 min read70 XP

  1. Define schema

    fields, types, required

  2. Model generates

    with schema in context/config

  3. Parse output

    attempt JSON.parse

  4. Validate against schema

    types, required fields

  5. Retry on failure

    or accept

The standard schema-guided generation pipeline.

Most structured-output systems combine two mechanisms: giving the model the schema as part of its instructions (so it knows the target shape) and validating the result programmatically afterward (so you catch the cases where it didn't comply), often with automatic retry using the validation error as feedback.

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