When to Apply This Skill

• A developer asks "what am I missing?" after initial test generation

• A coverage report (coverage.py, Istanbul, JaCoCo) is available and needs interpretation

• Pre-sprint planning requires a gap estimate and effort forecast for a module

• A team wants to know exactly what it takes to reach a coverage target (e.g. 80%)

Atomic Skills to Load First

Read this file before executing any step:

• ../unit-test-analyzing-code-coverage/SKILL.md

— All four coverage types (line / branch / function / statement), gap severity classification, tool integration guides (coverage.py, Istanbul, JaCoCo, coverlet), anti-pattern detection, and all three output report formats

Execution Steps

Read references/index.md before executing any step.

Step 1 — Receive Input

Accepted inputs (one or more):

• Coverage report: JSON (coverage.py / Istanbul), XML (JaCoCo / Cobertura), HTML

• Source code file (for structural gap analysis when no report is provided)

• Existing test file (to cross-reference against source for uncalled paths)

• Coverage target, e.g. "80% line, 75% branch" (defaults to these if not specified)

Step 2 — Analyze

Follow the full analysis workflow from ../unit-test-analyzing-code-coverage/SKILL.md :

• Parse coverage data or analyze source structure statically

• Identify: uncovered lines, untaken branches, uncalled functions, unhandled exceptions

• Classify every gap: CRITICAL | HIGH | MEDIUM | LOW

• Flag coverage anti-patterns (over-permissive mocks, integration tests masking gaps)

Step 3 — Produce Outputs

Generate all three deliverables defined in the unit-test-analyzing-code-coverage skill.

Output Deliverables

coverage_gap_report.md <- prioritized gap table (severity, location, description) recommended_tests.md <- specific named tests to write, with descriptions coverage_delta_estimate.md <- projected coverage % once recommended tests are added