Issue
Hallucinated Fields
The AI adds fields, keys, attributes, columns, or structured elements that were not declared, requested, or allowed by the expected schema.
What This Looks Like
The AI returns structured output with fields, keys, columns, attributes, labels, or sections that were not requested or allowed. The added fields may look plausible, helpful, or semantically related, but they are not part of the expected schema or output contract.
Why It Matters
Extra fields can break validation, imports, downstream parsing, review, and automation. Even when the extra content is understandable, it may create ambiguity about which structure is authoritative. In some workflows, hallucinated fields can also create false obligations or imply data that was never collected.
Structural Signal
The output exceeds the declared field boundary. The issue is not that the content is necessarily false; it is that the AI adds structural elements outside the allowed schema, template, or requested output surface.
Common Triggers
- The prompt gives examples that imply fields not present in the actual schema
- The model fills perceived gaps with plausible attributes
- The output contract does not explicitly forbid extra fields
- The AI tries to be helpful by adding context fields
- The schema changes but older field names remain in context
- The task mixes freeform explanation with strict structured output
When to Use This Issue
Use this Issue when the AI adds structured fields, keys, attributes, columns, or sections that are not declared, requested, or allowed.
When Not to Use This Issue
Do not use this Issue when a required field is missing, when a field has the wrong type, or when the whole structured response is invalid. Use this Issue when the problem is extra structure beyond the allowed boundary.
Category
Primary Pattern
Declared Patterns
Overreach
A structural condition where actions, effects, authority, or modifications extend beyond declared scope without authorization.
Schema Breakage
A structural condition where an instance, graph, payload, or object violates the type, shape, or rule requirements of a declared schema.
Unbounded Scope
A structural condition where an operation, authority, rule, or expansion has no declared upper bound, boundary, or termination condition.
Derived Primary Lenses
Boundary Compliance Lens
Evaluates observed structure against declared boundary posture, including allow, block, and exception rules.
Constraint Sufficiency Lens
Evaluates whether declared constraints are sufficient to eliminate structural degrees of freedom.
Interface Contract Lens
Compares declared interface structure to observed runtime structure to detect contract deviations.
Invariant Lens
Verifies that declared invariants are structurally enforceable and not contradicted by observed structure.
Isolation Boundary Lens
Evaluates whether structural constraints, effects, and regions remain contained within declared boundaries.
Overreach Lens
Detects structure that exceeds declared scope or authority reach.
Derived Secondary Lenses
Conflict Lens
Detects mutually incompatible constraints, claims, states, or declarations that cannot be simultaneously satisfied.
Escalation Gradient Lens
Measures structural growth or intensification across sequential executions, states, or transitions.
Propagation Lens
Traces how structural declarations, effects, or state changes propagate across boundaries or stages.
Search Intents
- hallucinated fields
- AI added extra JSON fields
- structured output has extra keys
- AI invented fields
- schema has unexpected fields
- output includes fields not requested