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CCA-F Part 5: A passing JSON schema proves your output has the right shape. It proves nothing about whether the values are true. That gap is the single most punishing area on the live exam #
A model response can pass every check in your JSON schema and still assert something that never happened. The skill that separates working systems from quiet disasters is knowing that syntactic validity is not semantic truth, and learning when to retry the call versus repair the schema itself.
In this article:You will learn why a
requiredfield can force a model to fabricate data, how to model honest absence with nullable types and an “unclear” enum, and why every credited answer in this domain separates syntax from semantics. We cover the
tool_useworkhorse pattern, validation-retry that fixes mis-extraction but never missing data, few-shot versus explicit criteria, independent review, and when the Message Batches API is right. By the end you will read a passing validator with healthy suspicion.
** Part 5 of “Passing the CCA-F: From Recall to Judgment,” a twelve-part guide that turns recall into the production**…