# Period-Decided Disposition

> A design rule that a duplicate is first counted by its distinguished copies and then read by the period of each derivation edge, so a periodic copy owes a comparator and a one-shot copy is a record whose source is repaired instead.

Record: `architecture:period-decided-disposition`
Kind: principle
Layer: [Execution Core](https://banes-lab.com/records/layer/execution-core.md)
Severity: recommended
Scope: duplicate, derivation
Canonical: https://banes-lab.com/ontology#architecture-period-decided-disposition

Listed in [Architecture principles](https://banes-lab.com/api/records/architecture.md), after [Declare-Before-Read Order](https://banes-lab.com/records/architecture/declare-before-read-order.md) and before [Derived Party Count](https://banes-lab.com/records/architecture/derived-party-count.md).

## Repair

- Refactored by: Count Distinguished Copies, Read Each Period, Repair the Source
- Detected by: a collapse that removed a copy written once against an earlier state of its source
- Violated by: collapsing every copy toward the source without asking whether any edge ever runs again
- Measured by: copies collapsed across one-shot edges
- Enforced by: coordination review

## Requires

- [Distinguished Copy](https://banes-lab.com/records/lexicon/distinguished-copy.md)
- [Derivation Period](https://banes-lab.com/records/lexicon/derivation-period.md)

## Reinforces

- [Single Source of Truth](https://banes-lab.com/records/architecture/single-source-of-truth.md)

## Enables

- [Traceable Guarantee](https://banes-lab.com/records/lexicon/traceable-guarantee.md)

## Conflicts with

- [Cyclic Tiebreak](https://banes-lab.com/records/architecture/cyclic-tiebreak.md)

## Contracts

- [Duplicate Disposition Walk](https://banes-lab.com/records/algorithms/duplicate-disposition-walk.md)

## Severity

- [recommended](https://banes-lab.com/records/vocabulary/severity-recommended.md)

## Category

- [Coordination Surfaces](https://banes-lab.com/records/architecture-category/coordination-surfaces.md)

## Linked from

- [Schema / Canonical Data / Semantics](https://banes-lab.com/ontology/principles/architecture-category-schema-canonical-data-semantics.md)
- [Coordination Surfaces](https://banes-lab.com/ontology/principles/architecture-category-coordination-surfaces.md)
- [Coordination Surfaces](https://banes-lab.com/ontology/lexicon/lexicon-category-coordination-surfaces.md)
- [Coordination](https://banes-lab.com/ontology/algorithms/algorithms-domain-coordination.md)
- [Severity levels](https://banes-lab.com/ontology/schema/the-vocabulary-severity.md)

## Evidence in the code

- [models/coordination.model.md](https://banes-lab.com/source/coordination/models/coordination.model.md.md)