---
id: object-model.coverage-dimensions
title: Coverage dimensions
summary: Organize cases by the behavior axes that matter to product correctness.
kind: reference
product_area: object_model
status: stable
updated: 2026-09-07
canonical: /docs/object-model/coverage-dimensions
---

# Coverage dimensions

## Definition

Coverage dimensions are the axes used to explain what behavior space a case set represents. A dimension can describe source freshness, request type, risk level, product area, policy boundary, or another classification that matters for review and benchmark interpretation.

Use this reference when a benchmark score is not enough and the team needs to ask which kinds of behavior are represented or missing.

## Fields, states, or lifecycle rules

- Dimensions should describe meaningful behavior axes, not arbitrary tags.
- Ontology values should keep each dimension's labels consistent enough for coverage planning.
- Coverage dimensions can reveal untested segments even when aggregate benchmark scores look strong.
- Changing a dimension schema can change how old benchmark evidence is interpreted.
- This page describes object semantics, not a public schema contract.

## Related objects

Coverage dimensions should be read with [Ontology](/docs/object-model/ontology), [Case pool](/docs/object-model/case-pool), [Benchmarks](/docs/object-model/benchmarks), and [Dimensions and ontology](/docs/coverage-engineering/dimensions-ontology).

{% example-demo title="Coverage dimensions boundary" %}
Dimension: Source support level.

Ontology values: Explicit support, implied support, conflicting source, no source.

Interpretation: A compatibility benchmark can show whether failures concentrate in cases where the source does not explicitly support the claim.
{% /example-demo %}

## Source confidence

Code-backed: Dimension and classification types plus the Dimensions and Ontology list and detail routes establish Dimensions, ontology values, origin, examples, and Case classification. Whether a Dimension is meaningful or complete remains a coverage-design judgment.

## Related task pages

{% related-card-grid title="Related task pages" %}
- [Dimensions and ontology](/docs/coverage-engineering/dimensions-ontology)
- [Dimensions and ontology](/docs/concepts/dimensions-and-ontology)
- [Ontology](/docs/object-model/ontology)
- [Product quickstart](/docs/quickstart)
- [Task index](/docs/operating-manual/task-index)
{% /related-card-grid %}