← LeaderboardThe Skill Leaderboard

tdd-workflow

Test-Driven Development workflow principles. RED-GREEN-REFACTOR cycle.

Published by sickn33 ↗sickn33/agentic-awesome-skills

Try your first task

tdd-workflow

Start a fresh conversation. Replace the highlighted placeholders.

Use tdd-workflow to implement [feature or fix] against [acceptance criteria] with tests written first and the RED-GREEN-REFACTOR cycle; once the test suite passes, stop and ask me whether to integrate the branch rather than merging or pushing.

Required inputs

[feature or fix]
[acceptance criteria]

User-approved starter prompt based on a pinned source version; check current skill requirements before running. Task evidence ↗

SKILL.md

name: tdd-workflowdescription: "Test-Driven Development workflow principles. RED-GREEN-REFACTOR cycle."risk: criticalsource: communitydate_added: "2026-02-27"

TDD Workflow

Write tests first, code second.

1. The TDD Cycle

🔴 RED → Write failing test
    ↓
🟢 GREEN → Write minimal code to pass
    ↓
🔵 REFACTOR → Improve code quality
    ↓
   Repeat...

2. The Three Laws of TDD

Write production code only to make a failing test pass
Write only enough test to demonstrate failure
Write only enough code to make the test pass

3. RED Phase Principles

What to Write

Focus	Example
Behavior	"should add two numbers"
Edge cases	"should handle empty input"
Error states	"should throw for invalid data"

RED Phase Rules

Test must fail first
Test name describes expected behavior
One assertion per test (ideally)

4. GREEN Phase Principles

Minimum Code

Principle	Meaning
YAGNI	You Aren't Gonna Need It
Simplest thing	Write the minimum to pass
No optimization	Just make it work

GREEN Phase Rules

Don't write unneeded code
Don't optimize yet
Pass the test, nothing more

5. REFACTOR Phase Principles

What to Improve

Area	Action
Duplication	Extract common code
Naming	Make intent clear
Structure	Improve organization
Complexity	Simplify logic

REFACTOR Rules

All tests must stay green
Small incremental changes
Commit after each refactor

6. AAA Pattern

Every test follows:

Step	Purpose
Arrange	Set up test data
Act	Execute code under test
Assert	Verify expected outcome

7. When to Use TDD

Scenario	TDD Value
New feature	High
Bug fix	High (write test first)
Complex logic	High
Exploratory	Low (spike, then TDD)
UI layout	Low

8. Test Prioritization

Priority	Test Type
1	Happy path
2	Error cases
3	Edge cases
4	Performance

9. Anti-Patterns

❌ Don't	✅ Do
Skip the RED phase	Watch test fail first
Write tests after	Write tests before
Over-engineer initial	Keep it simple
Multiple asserts	One behavior per test
Test implementation	Test behavior

10. AI-Augmented TDD

Multi-Agent Pattern

Agent	Role
Agent A	Write failing tests (RED)
Agent B	Implement to pass (GREEN)
Agent C	Optimize (REFACTOR)

Remember: The test is the specification. If you can't write a test, you don't understand the requirement.

When to Use

This skill is applicable to execute the workflow or actions described in the overview.

Limitations

Use this skill only when the task clearly matches the scope described above.
Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.