API Testing · Middle · Question 5 of 75

What does `additionalProperties: false` in a response schema catch?

1Fields whose values are null instead of strings
2Fields that are sent in a different order
3Unexpected fields, such as leaked internal data

Show the answer

Correct answer: Unexpected fields, such as leaked internal data

Explanation

Strict schemas detect new or leaked fields like passwordHash. Teams decide per API whether strictness helps or causes noise.

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