To prevent Claude from fabricating values when a requested field is absent from the source document, how…

Question

To prevent Claude from fabricating values when a requested field is absent from the source document, how should you engineer your JSON extraction schema?

Accepted Answer

A. Design the field with "type": ["string", "null"] and mark it as optional/nullable.

Answer

B. Add a system prompt instruction to "never fabricate data".

Answer

C. Set the tool parameter tool_choice: "any".

Answer

D. Reduce the temperature to 0.0 to eliminate hallucinations.

Question 193