productionos-tdd

Test-driven development with Codex is automated through a structured red-green-refactor loop that writes failing tests before any implementation, confirms the failure, applies minimal code changes, and refactors safely while updating coverage scopes.

The red-green-refactor loop is a test-driven development cycle that writes a failing test first, confirms the failure, implements minimal change to pass it, refactors safely, re-runs validation, and updates coverage to ensure tests drive design.

You start a TDD workflow by invoking the Codex-first cycle on a target feature or file, which begins by writing a failing test, confirming the failure, and then implementing minimal changes to pass the test before refactoring.

Yes, Codex test-driven development supports optional coverage scopes, allowing you to define coverage targets alongside specific features or files to validate changes and maintain quality throughout the red-green-refactor cycle.

Writing failing tests before implementation ensures that tests drive design rather than implementation details, enforcing red-green-refactor discipline so that only minimal, validated code changes are made and safely refactored.

A test-first development workflow may not suit rapid prototyping tasks, as it enforces strict red-green-refactor discipline by writing failing tests before implementation, adding structured validation overhead that may slow down exploratory feature development.