# Tdd

> Use when implementing or changing observable behavior test-first, fixing a bug with regression evidence, choosing a test seam for a planned slice, or when a test is hard to write, passes immediately, conflicts with source truth, or starts driving architecture.

- Skill: `hassan-mohiddin/tdd-2` (Agent Skill)
- Install (CLI): `npx skillmds@latest add hassan-mohiddin/tdd-2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/hassan-mohiddin/tdd-2/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: hassan-mohiddin (https://skillmd.com/u/hassan-mohiddin)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/hassan-mohiddin/tdd-2

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# Neutral Control

Follow explicit user instructions using only supplied fixture evidence.