Definition
Schema validation is the practice of verifying that an AI's structured output matches a defined data shape (types, required fields, value ranges) before downstream code consumes it. Tools include Zod (TypeScript), Pydantic (Python), and JSON Schema. Even with structured output APIs, validation provides a final safety net against drift, hallucinated fields, and edge-case malformations.
Example
Zod schema: z.object({ name: z.string().min(1), email: z.string().email(), age: z.number().int().positive() }). AI output validated before being inserted into a database.
When to use
Production AI pipelines, anywhere model output is consumed by typed systems.
Also known as
json schema