---
id: object-model.ontology
title: Ontology
summary: Use ontology values to classify cases consistently within each coverage dimension.
kind: reference
product_area: object_model
status: stable
updated: 2026-09-07
canonical: /docs/object-model/ontology
---

# Ontology

## Definition

Ontology values are the controlled labels used inside a coverage dimension. They keep case classification consistent enough for teams to plan coverage, compare benchmark segments, and explain gaps.

Use this reference when free-form tags are making coverage hard to read or when a benchmark segment needs stable vocabulary before results are trusted. Ontology values remain project-scoped foundations.

## Fields, states, or lifecycle rules

- Ontology values belong to dimensions; they should not drift into unrelated free-form tags.
- Values should be specific enough to separate meaningful behavior, but not so narrow that coverage becomes fragmented.
- Changing ontology values can change segment-level benchmark interpretation.
- Ontology should support coverage decisions, not replace expert judgment or policies.
- This page does not define a public taxonomy API.

## Related objects

Ontology should be read with [Coverage dimensions](/docs/object-model/coverage-dimensions), [Dimensions and ontology](/docs/coverage-engineering/dimensions-ontology), and [Generate a dimension schema](/docs/coverage-engineering/generate-dimension-schema).

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

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

Interpretation: Segment results are easier to trust because the team knows which support condition each case represents.
{% /example-demo %}

## Source confidence

Code-backed: Dimension types and the Dimension settings, ontology-row, and proposal components establish ontology members as labels owned by a Dimension and used for classification. Vocabulary quality and cross-reviewer consistency require project review.

## Related task pages

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