Encourages a Test-Driven Design approach, with behaviour-like descriptions. The output of the test run should resemble a specification. Tests will be co-located with the actual code files and follow the *.spec.ts naming convention. The final rule is "Definition of Done", which prompts the AI assistant to ensure that the code is in a good state with all tests passing and no errors or warnings.
Note: Linting examples assume `npm lint:fix` script exists.