tdd-guide (Codex Compatibility)

Use this skill for all feature work, bug fixes, and refactors that change behavior.

Routing Boundary

Use this skill when the user wants to build or change behavior through tests:

• TDD / test-driven development
• write failing tests first
• test-first implementation
• RED -> GREEN -> REFACTOR

Do not use it when tests are already failing and the user wants root cause; route that to systematic-debugging. Do not use it when the user only wants a test/coverage report; route that to generating-test-reports.

Core Rule

No production code before a failing test.

Workflow