---
id: coverage.plan-benchmark-coverage
title: Plan Benchmark Coverage
summary: Apply project Coverage Facets to one benchmark, inspect representation, and turn important gaps into concrete case or contribution work.
kind: task
product_area: coverage_engineering
status: stable
updated: 2026-09-07
canonical: /docs/coverage-engineering/plan-benchmark-coverage
---

# Plan Benchmark Coverage

Plan coverage by applying reusable project facets to one benchmark and comparing the intended behavior space with the selected dataset representation.

## Prerequisites

- A selected project and benchmark.
- A clear benchmark purpose.
- Relevant Dimensions, Project Topics, and Case Construction Patterns, or enough project knowledge to create them.
- Existing Cases or a plan for sourcing and constructing them.

## Steps

1. Review **Coverage Facets** at project scope. Confirm that Dimensions, Project Topics, and Case Construction Patterns describe reusable behavior structure rather than one benchmark's current case count.
2. Open the benchmark and select **Coverage Management → Get Started**.
3. Define the benchmark-specific coverage guidance and confirm setup readiness.
4. Open Coverage Management and inspect current dataset representation across the relevant facets and tuples.
5. Name important thin or absent combinations as Coverage Stories. Explain why each slice matters and what evidence would make it usable.
6. Route the gap according to its cause: Case Foundry or case sourcing for missing situations, Expert Contributions for missing judgment, Correctness Governance for missing standards, or Benchmark Datasets for missing selection.
7. Review generated or contributed cases in Case Review before relying on them.
8. Update dataset selection and create a new snapshot when the represented evidence changes materially.

## Object and state changes

This task can update benchmark coverage setup, representation guidance, Coverage Stories, Case Foundry work, case-review state, contribution requests, dataset selection, and snapshots. Project Coverage Facets may also change when the work discovers a reusable missing axis or construction pattern.

## Success criteria

- The benchmark purpose maps to explicit project Coverage Facets.
- Important combinations have selected evidence or a named gap.
- Each gap is routed to a responsible artifact or workstream.
- Constructed cases pass case review and Project Input Schema checks.
- Dataset snapshots make material coverage changes explicit.

## Common failure modes

- Using case count as the coverage goal.
- Creating benchmark-only tags where a reusable Dimension or Topic is needed.
- Treating response-variation guidance as coverage structure.
- Generating cases before defining which gap they should close.
- Trusting representation after selection changes without a new snapshot boundary.

{% example-demo title="Example: plan high-impact exception coverage" %}
The team maps exception type, source authority, and customer impact. Representation shows many low-impact ordinary cases but no high-impact cases with conflicting authority. A Coverage Story names the gap, an expert Contribution clarifies the controlling rule, and Case Foundry prepares cases for the missing tuple before a new snapshot is created.
{% /example-demo %}

## Related reference pages

{% related-card-grid title="Related reference pages" %}
- [Coverage Engineering](/docs/coverage-engineering)
- [Coverage Management](/docs/coverage-management)
- [Benchmark Datasets](/docs/benchmark-datasets)
{% /related-card-grid %}

## Related troubleshooting pages

{% related-card-grid title="Related troubleshooting pages" %}
- [Unbalanced coverage](/docs/troubleshooting/unbalanced-coverage)
- [Stale dimensions](/docs/troubleshooting/stale-dimensions)
- [Unrealistic synthetic cases](/docs/troubleshooting/unrealistic-synthetic-cases)
{% /related-card-grid %}

## Source confidence

Code-backed: current setup, overview, representation, Coverage Story, Case Foundry, and Case Review routes support this workflow.