Happy path

The primary, expected flow through a feature or user journey, where all inputs are valid and everything works as intended. Testing the happy path confirms that the core functionality works under normal conditions, but it represents only a fraction of the scenarios a tester should cover. A skilled tester uses the happy path as a baseline and then designs additional tests for invalid inputs, edge cases, boundary conditions, and failure states. AI tools can help extend coverage beyond the happy path quickly, but they depend on the tester having already understood the happy path before evaluating what the AI produces.