PAT-0190 - Contract Drift
A structural condition where a declared contract changes but connected structures, implementations, consumers, or expectations do not update in sync.
Primary Lenses
- LEN-0270 - Reconciliation Lens
Evaluates whether structural changes align with declared authority updates, version changes, or reconciliation rules.
- LEN-0170 - Convergence Lens
Compares parallel structural systems to determine whether they align under shared authority.
Secondary Lenses
- LEN-0180 - Determinism Lens
Evaluates whether identical structural inputs produce equivalent structural outputs across repeated executions.
Primary Issue Matches
- Actual Policy Differs From Declared Policy
The policy the AI or workflow actually follows differs from the policy that is documented, declared, displayed, or expected.
- Context Changes After Restore
Restoring, reopening, resuming, or reloading a task changes the context that the AI uses to continue the work.
- Old Output Expectations Survive Migration
Expectations from a prior model, prompt, schema, tool, or workflow survive a migration and continue shaping review or downstream handling after they should be replaced.
- Policy Update Not Reflected in Output
A policy, rule, standard, or instruction has been updated, but the AI output still follows the older version.
- Prompt Changed but Workflow Did Not
A prompt changes but the workflow, parser, review step, routing rule, or downstream expectation still assumes the old prompt behavior.
- Rubric Changed but Results Did Not
A review rubric, scoring rule, evaluation standard, or classification criterion changes, but AI results continue to reflect the old rubric.
- Same Contract Name Has Different Meanings
The same prompt, schema, field, policy, tool, or workflow contract name is used in different places with different meanings.
- Stale Context Affects Output
Old context, prior instructions, outdated references, or earlier task state continue to affect output after they should no longer apply.
- Version Change Breaks Existing Prompt
A prompt that previously produced usable results stops working after a version change in the model, tool, policy, schema, product surface, or workflow.
Supporting Issue Matches
- AI Forgets Earlier Constraints
A constraint, instruction, preference, or decision that should persist through the task stops affecting later output.
- Early Model Output Gets Overweighted Downstream
An early AI output receives too much authority in later workflow steps, decisions, reviews, or generated artifacts.
- Output Breaks After Model Change
Output that previously worked begins failing after a model, mode, runtime, or product behavior changes.
- Output Changed Without Declared Change
Output shape, content, format, fields, or behavior changes without a declared change to the prompt, schema, model, workflow, or governing rule.
- Prompt Behavior Changed Without Version Change
A prompt begins producing different behavior even though no prompt version, model version, workflow version, or declared dependency change is recorded.
- Revoked Approval Still Treated as Active
An approval, permission, exception, or authorization that was revoked continues to affect AI behavior or workflow decisions as if it were still active.
- Same Rule Declared in Multiple Places
The same rule, constraint, instruction, or policy appears in multiple places, creating redundancy and possible drift.
- Saved Reference No Longer Works
A saved source, citation, file reference, prompt reference, or workflow pointer previously worked but no longer resolves to the expected object or meaning.
- Small Change Produces Large Downstream Effects
A small prompt, schema, policy, output, or workflow change creates unexpectedly large effects in downstream steps.
- Tool Result Not Integrated Correctly
The AI receives a tool result but misreads, ignores, overwrites, misplaces, or fails to incorporate it correctly into the final output or workflow state.
Ontology Metadata
- Code
PAT-0190- Version
PAT-0190@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: Contract Drift.
Receipt impact: None