PAT-0160 - Schema Breakage

Primary Lenses

• LEN-0200 - Interface Contract Lens

  Compares declared interface structure to observed runtime structure to detect contract deviations.

• LEN-0210 - Invariant Lens

  Verifies that declared invariants are structurally enforceable and not contradicted by observed structure.

Secondary Lenses

• LEN-0150 - Conflict Lens

  Detects mutually incompatible constraints, claims, states, or declarations that cannot be simultaneously satisfied.

Primary Issue Matches

• AI Output Breaks Parser

  The AI output causes a parser, validator, importer, or structured-output consumer to fail.

• Invalid JSON Output

  The AI returns malformed JSON or structured output that cannot be parsed.

• Nested Fields Do Not Match

  The AI returns nested structured fields whose internal shape, hierarchy, parent-child relationship, or contained values do not match the expected structure.

• Wrong Field Types

  The AI returns fields with values whose types do not match the expected schema, such as strings where numbers, booleans, arrays, objects, or enums are required.

Supporting Issue Matches

• Downstream Steps Magnify Hallucinated Claim

  A hallucinated or unsupported claim from an AI output is reused by later workflow steps until it becomes more influential than the evidence supports.

• Duplicate Fields With Same Meaning

  The AI returns multiple fields, labels, sections, or structured elements that carry the same meaning and create ambiguity about which one should be used.

• Duplicate Output Sections

  The AI repeats sections, headings, blocks, or output areas in a way that creates redundancy, confusion, or downstream handling problems.

• Format Rule Too Weak

  The format instruction is too vague, incomplete, or optional to reliably produce output that satisfies the expected structure.

• Hallucinated Fields

  The AI adds fields, keys, attributes, columns, or structured elements that were not declared, requested, or allowed by the expected schema.

• Missing Required Fields

  The AI returns structured output that omits fields required by the schema, workflow, parser, form, or downstream consumer.

• Output Breaks the Next Step

  The AI output looks acceptable by itself but cannot be used by the next tool, workflow step, parser, reviewer, or downstream consumer.

• Schema Reference Loops Without Base Case

  A schema, field, type, object, or structured reference points through a loop without a base case that allows validation or interpretation to resolve.

• Single Field Carries Too Many Obligations

  One field, label, score, status, or structured value is expected to carry too many meanings, decisions, or workflow obligations.

• Tool Call Contract Mismatch

  The AI or agent calls a tool with names, arguments, types, modes, or shapes that do not match the declared tool interface.

• Validation Result Changes on Retry

  A validation, grading, review, classification, or pass/fail result changes after retry even though the input and declared validation rules did not change.

Ontology Metadata

Code

PAT-0160

Version

PAT-0160@0.1.0

Ontology release

0.1.0

Updated

2026-05-10T00:00:00Z

History

• 0.1.0 — 2026-05-10T00:00:00Z — Created

  Promoted reviewed Pattern ontology entry: Schema Breakage.

  Receipt impact: None

View full ontology changelog