Testing Plugin

Run the project's tests — auto-detects pytest, vitest, jest, cargo, go test; whole suite or a name pattern. Use when asked to run the tests and no tier, single file, or fix cycle is named.

Every tier in pyramid order — unit, then integration, then E2E. Use when running all tests before a PR or commit, or generating a coverage report.

One test file, fail-fast — Playwright, Vitest, Jest, pytest, cargo, go test. Use when running a single spec file, headed/debug mode, or serial single-worker WebGL tests.

Unit tier only — skips slow, integration, and E2E tests for sub-30s feedback. Use when checking units after a change, running tests affected since the last commit, or unit watch mode.

Configure testing infrastructure with CI/CD. Use when setting up tests, scaffolding test dirs, adding pre-commit hooks, GitHub Actions workflows, Codecov, or coverage badges.

Cached results from the last test run, no re-run — pass/fail counts, existing coverage report, history, flaky tests. Use when asked for current test status or standup health.

Analyze test results and create a fix plan with subagents. Use when triaging failing tests, analyzing JUnit XML, planning fixes for accessibility/security, or categorizing flaky/E2E failures.

Consult the test-architecture agent for strategy decisions. Use when asking about coverage gaps, test pyramid, framework selection, flaky-test remediation, or how to test X.

Playwright CLI browser automation — navigate, screenshot, fill forms, click. Use when automating browser tasks from the shell; 4-10x more token-efficient than Playwright MCP.

Vitest test runner — Vite-native, ESM, watch/UI mode, coverage, mocking, snapshots. Use when setting up tests for Vite projects, migrating from Jest, or needing fast execution.

Mutation testing with Stryker (TS/JS) and mutmut (Python). Use when finding weak tests that pass on mutated code, or improving test quality through mutation analysis.

Playwright E2E testing — cross-browser, visual regression, API testing, mobile emulation. Use when writing E2E tests or setting up automated UI testing for web apps.

odiff pixel-by-pixel image diffing. Use when comparing screenshots, detecting visual regressions, diffing before/after PNGs, asserting golden images.

Decide which test tier a change needs — unit, integration, or E2E — from its scope; runs nothing itself. Use when deciding how much of the suite to run after a change.

Evaluate whether a test suite actually tests what it aims to, using an adversarial pass plus a tests-hidden cold read, then verify every finding against the code. Use when a suite is green but you doubt it would catch a real regression.

Detect test smells, overmocking, flaky tests, and coverage issues. Use when reviewing tests, improving test quality, or analyzing test effectiveness and reliability.

Property-based testing with fast-check (TS/JS) and Hypothesis (Python). Use when generating test data, finding edge cases, testing properties, or writing QuickCheck-style tests.