unit-test-shifting-left-from-requirements

What This Skill Does

Generates unit tests and BDD scenarios directly from requirements, user stories, or PRDs — before any implementation code exists. Enables true shift-left testing by making tests the first artifact produced for a feature, not the last.

When to Apply This Skill

• A user story, acceptance criteria, or PRD is provided with no accompanying code
• A team wants tests ready before the developer starts implementation
• BDD / Gherkin scenarios are needed to align QA, dev, and product on expected behavior
• A feature's testability needs to be validated before implementation begins

TDD Framing

This skill operationalizes the Red phase of the Red-Green-Refactor cycle at scale. Every test skeleton produced here is a failing test by design — it cannot pass until the developer writes the implementation. Outputs from this skill should be committed to the repository before any implementation code is written, making the failing tests the formal definition of done for the feature.