Schema Validation

The primary mechanism for ensuring that every field in a generated JSON object matches its declared data type. Validation engines check that strings are not passed where integers are expected, and that arrays contain the correct element types.

• Prevents TypeError exceptions in consuming Python or TypeScript services
• Validates string formats like date-time, email, and URI
• Enforces numeric constraints such as minimum, maximum, and multipleOf
• Catches type mismatches before they corrupt databases or trigger retries

Beyond simple types, validation confirms that the hierarchical structure of the output is intact. This includes checking that required properties are present, that no additional properties exist in closed schemas, and that nested objects maintain their defined shape.

• Validates minProperties and maxProperties on objects
• Ensures minItems and maxItems constraints on arrays
• Confirms uniqueItems for arrays where duplicates are forbidden
• Recursively validates deeply nested conditional subschemas using if/then/else

Validates that generated values belong to a predefined set of acceptable options. This is critical for function calling where a model must select from a finite list of tool names or action types, preventing hallucinated or invalid commands.

• Restricts string fields to a specific enum list
• Enforces exact const values for versioning or routing keys
• Prevents the execution of undefined functions in API dispatchers
• Guarantees that state machine transitions reference valid states

Applies regular expression and semantic format validation to string values. This ensures that generated content like email addresses, UUIDs, and hostnames are not just strings, but syntactically correct and usable by downstream systems.

• Validates email, uri, uuid, hostname, and ipv4 formats
• Applies custom pattern regex constraints for domain-specific identifiers
• Ensures generated API endpoints are valid URIs before execution
• Catches malformed data that would fail silently in network calls

Enforces mathematical boundaries on numeric outputs to prevent illogical or dangerous values. This is essential for tool calling where parameters like temperature, max_tokens, or financial amounts must fall within safe operating ranges.

• Validates minimum and exclusiveMinimum bounds
• Checks maximum and exclusiveMaximum limits
• Enforces multipleOf for discrete increments like cents or time steps
• Prevents out-of-range values from causing API errors or infinite loops

Handles complex validation logic by combining multiple schemas using boolean operators. This allows for polymorphic validation where a field can match one of several possible structures, common in structured data extraction from heterogeneous documents.

• Validates allOf to merge multiple schema requirements
• Checks anyOf for fields that can satisfy at least one subschema
• Enforces oneOf for mutually exclusive structural options
• Resolves $ref pointers to reuse and compose schema definitions