tdd-workflow

tdd-workflow is a skill for Claude Code, Codex from cybernetix-lab/moss-harness. It costs 43 tokens per session (3,075 once invoked), scanned A, original, MIT.

A test-driven development workflow for building features, fixing bugs, and refactoring code. Test-driven development, or TDD, means writing tests before the code they check, including unit, integration, and browser-based end-to-end tests.

In plain words
What is it for?
Use it for new features, bug fixes, refactors, API endpoints, and UI components that need tested behaviour across individual functions, connected services, and complete user flows.
Why use it?
It makes expected behaviour explicit before implementation and checks both normal and failure cases. The workflow also requires at least 80% test coverage and Git checkpoints during development.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it for new features, bug fixes, refactors, API endpoints, and UI components that need tested behaviour across individual functions, connected services, and complete user flows.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/cybernetix-lab/moss-harness/tdd-workflow
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.

Any agent
npx skills add cybernetix-lab/moss-harness --skill tdd-workflow
Clone the repo
git clone --depth 1 https://github.com/cybernetix-lab/moss-harness

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for tdd-workflow

README.md
[![agentmods](https://agentmods.dev/badge/skills/cybernetix-lab/moss-harness/tdd-workflow/github.svg)](https://agentmods.dev/skills/cybernetix-lab/moss-harness/tdd-workflow)
Your own site
<a href="https://agentmods.dev/skills/cybernetix-lab/moss-harness/tdd-workflow"><img src="https://agentmods.dev/badge/skills/cybernetix-lab/moss-harness/tdd-workflow/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for tdd-workflow

Your own site · 80×15
<a href="https://agentmods.dev/skills/cybernetix-lab/moss-harness/tdd-workflow"><img src="https://agentmods.dev/badge/skills/cybernetix-lab/moss-harness/tdd-workflow.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,075 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found 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 5.1 $0.00043 $0.03075
Opus 5 $0.00022 $0.01537
Sonnet 5 $0.00009 $0.00615
Haiku 4.5 $0.00004 $0.00308

Measured 9d ago against content hash 934c453594ce, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, 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 9d 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

Copies of this mod

2 near-identical copies found in the catalogue:

integrations/skills/tdd-workflow/SKILL.md · 464 lines

How it starts

The opening of the file, as written. The whole thing — 464 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

4. Git Checkpoints

  • If the repository is under Git, create a checkpoint commit after each TDD stage
  • Do not squash or rewrite these checkpoint commits until the workflow is complete
  • Each checkpoint commit message must describe the stage and the exact evidence captured
  • Count only commits created on the current active branch for the current task
  • Do not treat commits from other branches, earlier unrelated work, or distant branch history as valid checkpoint evidence
  • Before treating a checkpoint as satisfied, verify that the commit is reachable from the current HEAD on the active branch and belongs to the current task sequence
  • The preferred compact workflow is:
    • one commit for failing test added and RED validated
    • one commit for minimal fix applied and GREEN validated
    • one optional commit for refactor complete
  • Separate evidence-only commits are not required if the test commit clearly corresponds to RED and the fix commit clearly corresponds to GREEN

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.

Read the full file on GitHub · 464 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. 9d ago First seen · 464 lines · 43 tokens per session scan A 934c453594ce

Subscribe to this mod's changes

tdd-workflow is a skill published in the GitHub repository cybernetix-lab/moss-harness (135 stars, last pushed 3mo ago), licensed MIT. It adds 43 tokens to every session and 3,075 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.