tdd-workflow

A test-driven development workflow, meaning you write tests that describe expected behaviour before writing the code. It covers unit, integration, and end-to-end tests, including browser-based checks.

In plain words
What is it for?
Use it when building features, fixing bugs, refactoring code, adding API endpoints, or creating components that need broad automated testing.
Why use it?
It gives feature work, bug fixes, and refactoring a defined way to check that changes work and old behaviour still works. It also requires testing errors, edge cases, and boundary conditions.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/mit-network/everything-claude-code/tdd-workflow
Any agent
npx skills add mit-network/everything-claude-code --skill tdd-workflow
Clone the repo
git clone --depth 1 https://github.com/mit-network/everything-claude-code

Made for: Claude Code, Codex.

Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,435 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 89% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00043 $0.02435
Opus 5 $0.00022 $0.01218
Sonnet 5 $0.00009 $0.00487
Haiku 4.5 $0.00004 $0.00244

Measured 2d ago against content hash 63249998befb, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

tdd-workflow scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

89% identical to tdd-workflow — 13 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/tdd-workflow/SKILL.md · 411 lines

How it starts

The opening of the file, as written. The whole thing — 411 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Test-Driven Development Workflow

This skill ensures all code development follows TDD principles with comprehensive test coverage.

When to Activate

  • Writing new features or functionality
  • Fixing bugs or issues
  • Refactoring existing code
  • Adding API endpoints
  • Creating new components

Core Principles

1. Tests BEFORE Code

ALWAYS write tests first, then implement code to make tests pass.

2. Coverage Requirements

  • Minimum 80% coverage (unit + integration + E2E)
  • All edge cases covered
  • Error scenarios tested
  • Boundary conditions verified

3. Test Types

Unit Tests
  • Individual functions and utilities
  • Component logic
  • Pure functions
  • Helpers and utilities
Integration Tests
  • API endpoints
  • Database operations
  • Service interactions
  • External API calls
E2E Tests (Playwright)
  • Critical user flows
  • Complete workflows
  • Browser automation
  • UI interactions

TDD Workflow Steps

Step 1: Write User Journeys

As a [role], I want to [action], so that [benefit]

Example:
As a user, I want to search for markets semantically,
so that I can find relevant markets even without exact keywords.

Step 2: Generate Test Cases

For each user journey, create comprehensive test cases:

describe('Semantic Search', () => {
  it('returns relevant markets for query', async () => {
    // Test implementation
  })

  it('handles empty query gracefully', async () => {
    // Test edge case
  })

  it('falls back to substring search when Redis unavailable', async () => {
    // Test fallback behavior
  })

  it('sorts results by similarity score', async () => {
    // Test sorting logic
  })
})

Step 3: Run Tests (They Should Fail)

npm test
# Tests should fail - we haven't implemented yet

Step 4: Implement Code

Write minimal code to make tests pass:

// Implementation guided by tests
export async function searchMarkets(query: string) {
  // Implementation here
}

Step 5: Run Tests Again

npm test
# Tests should now pass

Read the full file on GitHub · 411 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 411 lines · 43 tokens per session scan A 63249998befb

Subscribe to this mod's changes

tdd-workflow is a skill published in the GitHub repository mit-network/everything-claude-code (76 stars, last pushed 5mo ago), licensed MIT. It adds 43 tokens to every session and 2,435 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 89% identical to tdd-workflow, differing in 13 lines, and is treated as a copy.

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