test-driven-development SKILL.md skillA

This file is byte-identical to the first copy the registry indexed, one of 6 indexed copies. Same content hash, so the same checks give both the same grade.

test-driven-development from joahanmorales/upiixia-agentic-kit is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

mdr add joahanmorales/upiixia-agentic-kit/test-driven-development@git:20261006.308cb43

Pins git:20261006.308cb43 in mdr.lock. Pin the fingerprint instead.

Audit grade

A, 17 of 17 checks passed

Kind

SKILL.md skill

Repository

joahanmorales/upiixia-agentic-kit

Path

kit/.uak/skills/test-driven-development/SKILL.md

Versions recorded

1

Latest version

git:20261006.308cb43, committed Oct 6, 2026

Size

9,578 bytes

Repository stars

9

License

MIT

Use when implementing any feature or bugfix, before writing implementation code.

Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.

What the file says

# Test-Driven Development (TDD)

## Overview

Write the test first. Watch it fail. Write minimal code to pass.

**Core principle:** If you didn't watch the test fail, you don't know if it tests the right thing.

**Violating the letter of the rules is violating the spirit of the rules.**

## When to Use

**Always:**
- New features
- Bug fixes
- Refactoring
- Behavior changes

**Exceptions (ask your human partner):**
- Throwaway prototypes
- Generated code
- Configuration files

Thinking "skip TDD just this once"? Stop. That's rationalization.

## The Iron Law

```
NO PRODUCTION CODE WITHOUT A FAILING TEST FIRST
```

Write code before the test? Delete it. Start over.

**No exceptions:**
- Don't keep it as "reference"
- Don't "adapt" it while writing tests
- Don't look at it
- Delete means delete

Implement fresh from tests. Period.

## Red-Green-Refactor

```dot
digraph tdd_cycle {
    rankdir=LR;
    red [label="RED\nWrite failing test", shape=box, style=filled, fillcolor="#ffcccc"];
    verify_red [label="Verify fails\ncorrectly", shape=diamond];
    green [label="GREEN\nMinimal code", shape=box, style=filled, fillcolor="#ccffcc"];
…

Read the whole file at its exact version.

How to install

mdr add joahanmorales/upiixia-agentic-kit/test-driven-development@sha256:64b03fce4aee5a97

[![mdr](https://markdownregistry.com/badge/art_3cqtxxcozkzwydrp.svg)](https://markdownregistry.com/a/art_3cqtxxcozkzwydrp)

Versions

The registry has recorded 1 version of this file, committed on Oct 6, 2026.

Audit of the latest version

Source

API

GET https://markdownregistry.com/api/v1/artifacts/art_3cqtxxcozkzwydrp
GET https://markdownregistry.com/api/v1/resolve?ref=joahanmorales/upiixia-agentic-kit/test-driven-development
GET https://markdownregistry.com/api/v1/blob/64b03fce4aee5a97a93160cea8111f3ba13a17b7c001db4bd5836d67fd10705d

Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.

Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.

More from joahanmorales/upiixia-agentic-kit

Every file in joahanmorales/upiixia-agentic-kit

Other files named test-driven-development

Browse by kind, by grade A, or by owner.