Individual skill
tdd
Test-Driven Development methodology and red-green-refactor workflow (formerly test-tdd). This skill should be used when practicing TDD, writing tests first, designing tests before implementation, or reviewing test-first approaches. Triggers on "write tests first", "test before code", "red green refactor", "test driven development". This skill does NOT cover Vitest framework specifics (use vitest skill) or API mocking with MSW (use msw skill).
skills/.curated/tdd/SKILL.md
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- Last checked
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- Repository last updated
- Aug 15, 2026
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Observed agent integration: codex
- testing Derived category
- engineering Derived category
- operations Derived category
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AGENTS.mddoc · 8,626 bytesREADME.mddoc · 4,331 bytesSKILL.mdcore · 5,514 bytesassets/templates/_template.mddoc · 774 bytesmetadata.jsonasset · 1,150 bytesreferences/_sections.mddoc · 1,934 bytesreferences/assert-custom-matchers.mddoc · 2,312 bytesreferences/assert-error-messages.mddoc · 1,888 bytesreferences/assert-no-assertions-antipattern.mddoc · 2,231 bytesreferences/assert-snapshot-testing.mddoc · 2,143 bytesreferences/assert-specific-assertions.mddoc · 1,941 bytesreferences/cycle-maintain-test-list.mddoc · 2,010 bytesreferences/cycle-minimal-code-to-pass.mddoc · 1,811 bytesreferences/cycle-refactor-after-green.mddoc · 1,856 bytesreferences/cycle-small-increments.mddoc · 2,135 bytesreferences/cycle-verify-test-fails-first.mddoc · 1,847 bytesreferences/cycle-write-test-first.mddoc · 1,999 bytesreferences/data-avoid-mystery-guests.mddoc · 2,034 bytesreferences/data-builder-pattern.mddoc · 2,623 bytesreferences/data-minimal-setup.mddoc · 1,824 bytesreferences/data-unique-identifiers.mddoc · 2,328 bytesreferences/data-use-factories.mddoc · 2,305 bytesreferences/design-aaa-pattern.mddoc · 2,085 bytesreferences/design-avoid-logic-in-tests.mddoc · 2,351 bytesreferences/design-descriptive-test-names.mddoc · 1,788 bytesreferences/design-one-assertion-per-test.mddoc · 2,292 bytesreferences/design-test-behavior-not-implementation.mddoc · 2,012 bytesreferences/design-test-edge-cases.mddoc · 2,490 bytesreferences/isolate-deterministic-tests.mddoc · 2,201 bytesreferences/isolate-mock-external-dependencies.mddoc · 1,839 bytesreferences/isolate-no-shared-state.mddoc · 1,822 bytesreferences/isolate-prefer-stubs-over-mocks.mddoc · 2,421 bytesreferences/isolate-use-dependency-injection.mddoc · 2,520 bytesreferences/org-file-structure.mddoc · 1,639 bytesreferences/org-group-by-behavior.mddoc · 2,133 bytesreferences/org-parameterized-tests.mddoc · 2,440 bytesreferences/org-setup-teardown.mddoc · 2,378 bytesreferences/org-test-utilities.mddoc · 2,391 bytesreferences/perf-avoid-network-calls.mddoc · 2,086 bytesreferences/perf-avoid-sleep.mddoc · 2,219 bytesreferences/perf-fast-unit-tests.mddoc · 1,755 bytesreferences/perf-fix-flaky-tests.mddoc · 2,284 bytesreferences/perf-parallelize-tests.mddoc · 2,319 bytesreferences/strat-coverage-targets.mddoc · 2,253 bytesreferences/strat-e2e-critical-paths.mddoc · 2,510 bytesreferences/strat-integration-boundaries.mddoc · 2,448 bytesreferences/strat-mutation-testing.mddoc · 2,124 bytesreferences/strat-test-pyramid.mddoc · 2,373 bytes
Read excerpt
# Community Test-Driven Development Best Practices
Comprehensive guide to Test-Driven Development practices, designed for AI agents and LLMs. Contains 42 rules across 8 categories, prioritized by impact to guide test writing, refactoring, and code generation.
## When to Apply
Reference these guidelines when:
- Writing new tests using TDD workflow
- Implementing the red-green-refactor cycle
- Designing test structure and organization
- Creating test data and fixtures
- Reviewing or refactoring existing test suites
## TDD Workflow