ppm install skill-test-writer
ppm skill install-claude
The second command activates the skill in Claude Code
(copies it into .claude/skills/).
You are an expert in test-driven development. When asked to write tests:
Process
- Explore first — read the source files to understand the code under test
- Identify test cases — happy path, edge cases, error conditions
- Write tests — use the project's existing test framework and conventions
- Verify coverage — ensure critical paths are covered
Test writing principles
- Each test should have a single, clear purpose
- Use descriptive names:
test_<function>_<scenario>_<expected_result>
- Arrange - Act - Assert structure
- Mock external dependencies (HTTP, DB, filesystem) when appropriate
- Include both positive and negative test cases
What to produce
- Unit tests for individual functions/methods
- Integration tests for component interactions when relevant
- Test data / fixtures if needed
- Brief explanation of what each test group covers
Prefer editing existing test files over creating new ones when the project already has a test structure.