Use when you need to write unit tests for Spring Boot applications — including pure unit tests with @ExtendWith(MockitoExtension.class) for @Service/@Component, slice tests with @WebMvcTest and @MockitoBean for controllers, @JsonTest for JSON serialization, parameterized tests with @CsvSource/@MethodSource, test profiles, and @TestConfiguration. For framework-agnostic Java use @131-java-testing-unit-testing. For integration tests use @322-frameworks-spring-boot-testing-integration-tests. This should trigger for requests such as Review Java code for Spring Boot unit tests; Apply best practices for Spring Boot unit tests in Java code; Write Mockito-first unit tests for Spring Boot services; Avoid unnecessary @SpringBootTest in Spring unit tests; Review Spring Boot slice-free unit test design. Part of Plinth Toolkit