# Story: TDD Agent Validation Test

**Story ID**: TEST-TDD-001
**Epic**: BMAD Method Testing
**Priority**: High
**Status**: Approved
**Sprint**: Current
**Story Points**: 3
**Assigned To**: TDD Developer Agent (Ted)
**Created By**: Scrum Master
**Date Created**: 2025-01-04

## Story Description

As a BMAD Method developer, I need to validate that the TDD Developer Agent (dev-tdd) works correctly with the RED-GREEN-REFACTOR workflow, so that we can ensure the agent properly enforces test-driven development practices.

This is a minimal test story designed to validate:

1. The agent can load and process stories correctly
2. The RED phase generates failing tests
3. The GREEN phase implements code to pass tests
4. The REFACTOR phase improves code quality
5. The workflow completes successfully

## Acceptance Criteria

### AC-001: Calculator Add Function

**Given** a Calculator class is needed
**When** the add method is called with two numbers
**Then** it should return the sum of those numbers

### AC-002: Calculator Subtract Function

**Given** a Calculator class exists
**When** the subtract method is called with two numbers
**Then** it should return the difference (first - second)

### AC-003: Error Handling

**Given** the Calculator class
**When** invalid input is provided (non-numeric)
**Then** it should raise an appropriate error with a clear message

## Tasks/Subtasks

- [ ] Task 1: Implement Calculator class with add method
  - [ ] Generate failing tests for add method (RED)
  - [ ] Implement add method to pass tests (GREEN)
  - [ ] Refactor for code quality (REFACTOR)

- [ ] Task 2: Implement subtract method
  - [ ] Generate failing tests for subtract method (RED)
  - [ ] Implement subtract method to pass tests (GREEN)
  - [ ] Refactor for code quality (REFACTOR)

- [ ] Task 3: Add error handling
  - [ ] Generate failing tests for error cases (RED)
  - [ ] Implement error handling (GREEN)
  - [ ] Refactor and consolidate error handling (REFACTOR)

## Technical Notes

- Use Python for implementation
- Follow PEP 8 style guidelines
- Tests should use pytest or unittest
- Each method should have comprehensive test coverage
- Focus on clarity over complexity

## Definition of Done

- [ ] All acceptance criteria are met
- [ ] All tests are passing
- [ ] Code follows project conventions
- [ ] RED-GREEN-REFACTOR cycle documented for each task
- [ ] No linting errors
- [ ] Test coverage is 100% for the Calculator class

## Dev Agent Record

### Context Reference

- Story Context: `/home/bj/python/BMAD-METHOD/test-stories/story-context-tdd-validation.json`

### Debug Log

_Agent execution notes will be added here during development_

### Completion Notes

_Final summary will be added upon story completion_

## File List

_Files created/modified will be listed here_

## Change Log

_Changes will be documented here as work progresses_

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## Notes for TDD Agent Testing

This story is intentionally simple to focus on testing the agent's workflow mechanics rather than complex implementation challenges. The Calculator class provides:

1. **Simple functionality** - Easy to test and implement
2. **Multiple methods** - Tests the agent's ability to handle multiple tasks
3. **Error handling** - Tests the agent's ability to implement defensive code
4. **Clear acceptance criteria** - Unambiguous requirements for testing

The agent should execute this story using the `*develop-tdd` workflow command after loading the story with `*load-story`.

## Expected Outcomes

When the TDD Developer Agent successfully completes this story:

1. A `calculator.py` file should be created with the Calculator class
2. A test file (e.g., `test_calculator.py`) should be created with comprehensive tests
3. All tests should pass
4. The implementation should be clean and well-refactored
5. Each task should show clear RED-GREEN-REFACTOR progression
6. The story status should be updated to "Ready for Review"

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_This test story was created to validate the TDD Developer Agent functionality_