# Small Change Produces Large Downstream Effects

## Ontology Metadata

Code: ISS-0106
Version: ISS-0106@0.1.0
Ontology release: 0.1.0
Updated: 2026-05-10T00:00:00Z
Canonical URL: /workbench/issues/small-change-produces-large-downstream-effects/

## Summary

A small prompt, schema, policy, output, or workflow change creates unexpectedly large effects in downstream steps.

## Category

- CAT-0110 — Spread & Escalation
  - URL: /workbench/categories/spread-and-escalation/
  - Summary: Problems where small errors, local exceptions, risk signals, retries, permissions, or outputs spread downstream, grow in consequence, or trigger broader actions.

## Primary Pattern

- PAT-0360 — Propagation Amplification
  - URL: /workbench/patterns/propagation-amplification/
  - Summary: A structural condition where an effect, declaration, authority, constraint, or state increases in scope or intensity as it propagates beyond declared bounds.

## Declared Patterns

- PAT-0360 — Propagation Amplification
  - URL: /workbench/patterns/propagation-amplification/
  - Summary: A structural condition where an effect, declaration, authority, constraint, or state increases in scope or intensity as it propagates beyond declared bounds.
- PAT-0190 — Contract Drift
  - URL: /workbench/patterns/contract-drift/
  - Summary: A structural condition where a declared contract changes but connected structures, implementations, consumers, or expectations do not update in sync.
- PAT-0180 — Compatibility Violation
  - URL: /workbench/patterns/compatibility-violation/
  - Summary: A structural condition where a graph, object, behavior, or runtime state exceeds a declared compatibility envelope without an authorized exception.

## Derived Primary Lenses

- LEN-0130 — Compatibility Envelope Lens
  - URL: /workbench/lenses/compatibility-envelope-lens/
  - Summary: Determines whether structure fits within declared runtime, platform, version, or support constraints.
- LEN-0170 — Convergence Lens
  - URL: /workbench/lenses/convergence-lens/
  - Summary: Compares parallel structural systems to determine whether they align under shared authority.
- LEN-0190 — Escalation Gradient Lens
  - URL: /workbench/lenses/escalation-gradient-lens/
  - Summary: Measures structural growth or intensification across sequential executions, states, or transitions.
- LEN-0250 — Propagation Lens
  - URL: /workbench/lenses/propagation-lens/
  - Summary: Traces how structural declarations, effects, or state changes propagate across boundaries or stages.
- LEN-0270 — Reconciliation Lens
  - URL: /workbench/lenses/reconciliation-lens/
  - Summary: Evaluates whether structural changes align with declared authority updates, version changes, or reconciliation rules.

## Derived Secondary Lenses

- LEN-0120 — Boundary Compliance Lens
  - URL: /workbench/lenses/boundary-compliance-lens/
  - Summary: Evaluates observed structure against declared boundary posture, including allow, block, and exception rules.
- LEN-0180 — Determinism Lens
  - URL: /workbench/lenses/determinism-lens/
  - Summary: Evaluates whether identical structural inputs produce equivalent structural outputs across repeated executions.
- LEN-0290 — Variance / Entropy Lens
  - URL: /workbench/lenses/variance-entropy-lens/
  - Summary: Measures structural variability across repeated or comparable evaluations and identifies divergence beyond expected bounds.

## Search Intents

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- small AI change caused big workflow impact
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- minor schema change broke workflow
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- downstream effects from small change