test-strategy

TDD works best for codified and articulated specifications because the requirements are explicitly defined enough to write failing tests upfront. For tacit specifications where behavior is not fully defined, exploratory testing after implementation is recommended over strict TDD.

Red-gate validation is a structured testing workflow that ensures robust test coverage by validating test failure before implementation and declaring immutability for verified components. It guides developers through a strict progression to prevent regression.

You should use exploratory testing instead of TDD when a task's specification is classified as tacit knowledge. Tacit specifications lack explicit requirements, making test-after exploratory approaches more appropriate than writing tests first.

You determine specification classification by analyzing task descriptions and project artifacts. Codified specs are strictly documented, articulated specs are explicitly discussed but flexible, and tacit specs rely on implicit understanding without formal documentation.

The limitation of using TDD for tacit specifications is that implicit requirements cannot be easily translated into upfront failing tests. Forcing TDD on tacit knowledge causes wasted effort and incorrect testing methodologies, requiring an exploratory test-after approach instead.