Test.
When the test suite tests what was written instead of what was needed. The skill that flips the order: failing test first, minimum code to pass, refactor under green.
5 reference docs · 92 KB installed · stryx-test
Red, Green, Refactor. Edge Cases. Vitest. Playwright.
For engineers who want tests that catch real bugs, not tests that decorate the diff. This skill enforces test-first discipline so requirements get encoded before implementation. Covers the red-green-refactor loop, edge case matrix generation (empty, null, max int, unicode, newlines), Vitest config patterns (describe nesting, beforeEach reset, vi.mock, fake timers), Playwright E2E with Page Object Model, and coverage that excludes auto-generated code so the number means something.
Four recipes.
Red-green-refactor
RED: write a failing test that captures the requirement. GREEN: write the minimum code to make it pass (do not over-engineer). REFACTOR: improve structure with the test as safety net. Repeat.
Edge case matrix
For each input: empty, null, undefined, zero, negative, max int, unicode, very long, with newlines, with special chars. Generate the matrix BEFORE writing the test.
Vitest patterns
describe nesting for context. beforeEach reset state. vi.mock for module mocks. vi.useFakeTimers for time-dependent. Snapshot tests ONLY for stable serialization.
Playwright E2E
One test per critical user journey. Page Object Model for reusable selectors. Wait for state, not timeouts. Screenshot diff for visual regression.
It composes.
Skills compose into workflows. Test is rarely the only skill you will use — it pairs naturally with these others in the library.
One command.
Installs only stryx-test (skip the other 19) into ~/.claude/skills/stryx-test/.
Free for all use.
Stryx Labs License v1.0. Use Test in personal, commercial, internal, and production work. No attribution required.