testing-reviewer

Analyze code diffs to identify test coverage gaps and produce JSON findings.

Updated Aug 27, 2026
One-click install
npx skills add https://github.com/xbpk3t/ce-codex --skill testing-reviewer
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: testing-reviewer
Source: https://github.com/xbpk3t/ce-codex/tree/main/skills/testing-reviewer
Command: npx skills add https://github.com/xbpk3t/ce-codex --skill testing-reviewer

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This Skill helps reviewers determine whether tests in a code diff actually validate behavior and catch regressions rather than merely existing. It surfaces false confidence caused by weak assertions, implementation-coupled checks, and missing error-path coverage so reviewers can prioritize meaningful tests.

Core Features & Use Cases

  • Detect untested branches in new code: Trace new conditional logic and confirm at least one test exercises each behavior-changing branch.
  • Identify tests that don't assert behavior: Flag tests that only check for no-throw, truthiness, or that validate mocks instead of real outputs.
  • Find brittle implementation-coupled tests: Point out snapshots or assertions that break on refactor without behavior changes.
  • Flag missing edge-case and error-path coverage: Highlight catch blocks, fallback branches, and error returns that lack tests.
  • Use Cases: Pull request reviews, CI gating for test quality, and pre-merge checks to avoid shipping false-positive test coverage.

Quick Start

Ask the testing-reviewer to analyze the pull request diff and return JSON findings listing untested branches, weak or brittle tests, and residual risks with confidence indicators.

Frequently Asked Questions about testing-reviewer

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I detect untested branches in a pull request diff?▼

To detect untested branches in a pull request diff, apply test coverage analysis to the changes to identify untested branches and missing error-path coverage. This surfaces false confidence caused by weak assertions and implementation-coupled checks.

What are vacuous assertions in unit tests and how do I find them?▼

Vacuous assertions in unit tests are weak checks that validate mocks or truthiness instead of real outputs. You identify them by analyzing test changes to flag tests that only check for no-throw execution, ensuring tests actually validate behavior.

How do I find brittle implementation-coupled tests during code review?▼

Finding brittle implementation-coupled tests during code review involves analyzing assertions and snapshots that break during refactoring without actual behavior changes. Flagging these tests helps prioritize meaningful tests that validate outcomes rather than internal structure.

Can I automate test quality checks in CI for missing error-path coverage?▼

You can automate test quality checks in CI by analyzing pull request diffs to detect missing error-path coverage and vacuous assertions. The process outputs JSON-formatted findings enumerating testing gaps and residual risks suitable for CI gating.

How do I assess residual risks and confidence in unit test coverage?▼

You assess residual risks and confidence in unit test coverage by evaluating code diffs for untested branches and weak assertions. This generates JSON-formatted findings enumerating specific testing gaps alongside confidence indicators for code review.