test-critic

name	test-critic
user-invocable	false
description	Evaluates test quality — coverage analysis, mutation testing (do tests actually catch bugs?), test gap detection, and test code quality scoring. Supports Jest, Vitest, pytest. Use after writing tests to verify they're meaningful.
triggers	["test quality","check tests","test coverage","mutation testing","test critic"]
category	development
maturity	stable
tags	["test-quality","mutation-testing","coverage","jest","pytest"]

test-critic

Evaluates test quality — not just "do tests pass" but "do tests actually catch bugs?"

Quick Start

# Full audit
test-critic /path/to/project --full

# Quick (coverage only, no mutations)
test-critic /path/to/project --quick

# Individual scripts
node ${CLAUDE_SKILLS_DIR:-$HOME/.claude-agent/.claude/skills}/test-critic/scripts/coverage.cjs /path/to/project
node ${CLAUDE_SKILLS_DIR:-$HOME/.claude-agent/.claude/skills}/test-critic/scripts/gaps.cjs /path/to/project
node ${CLAUDE_SKILLS_DIR:-$HOME/.claude-agent/.claude/skills}/test-critic/scripts/quality.cjs /path/to/project
node ${CLAUDE_SKILLS_DIR:-$HOME/.claude-agent/.claude/skills}/test-critic/scripts/mutate.cjs /path/to/project --limit 50
node ${CLAUDE_SKILLS_DIR:-$HOME/.claude-agent/.claude/skills}/test-critic/scripts/report.cjs /path/to/project

Options

Flag	Description
--quick	Coverage + gaps + quality only (no mutations)
--full	Everything including mutation testing
--framework jest|vitest|pytest|auto	Test framework (default: auto-detect)
--mutate-limit N	Max mutations to try (default: 100)
--output-dir DIR	Where to write reports
--format md|json|both	Report format

Components

1. coverage.cjs — Runs tests with coverage, identifies untested files, happy-path-only files, critical files with low coverage
2. mutate.cjs — Lightweight mutation testing: modifies source code and checks if tests catch the change
3. gaps.cjs — Static analysis to find untested error handlers, null checks, boundary conditions, division-by-zero
4. quality.cjs — Analyzes test code itself: missing assertions, poor names, excessive mocking, hardcoded sleeps
5. review.cjs — Orchestrator that runs all components and generates final report
6. report.cjs — Combines all results into scored report with prioritized test suggestions

Output

• coverage-analysis.json — Coverage breakdown
• test-gaps.json — Identified test gaps with suggestions
• test-quality.json — Test code quality issues
• mutation-results.json — Mutation testing results
• test-critic-report.json — Combined report with health score
• test-critic-report.md — Human-readable markdown report

Supported Frameworks

• Jest (auto-detected)
• Vitest
• Node.js test runner
• pytest

Dependencies

Node.js built-in modules only. Shells out to test runners.