Phase 1: Spec-Driven Development · 45 min · Claude Code · Python

Writing Your First Spec

A spec describes what must be true. The moment it describes how, it stops being durable.

What you will learn

Structure a spec into problem statement, acceptance criteria, constraints, and test cases
Apply the 'don't mention the implementation' rule to keep a spec durable across technology changes
Distinguish a testable, measurable acceptance criterion from a vague one
Write and lint a real spec for your own course-long product

Introduction

Writing Your First Spec

Objective

Lint a real spec.md for implementation leakage in Acceptance Criteria and vague, unquantified acceptance criteria, and demonstrate the difference between a bad spec and a clean one.

Unlock the full lesson

You've read the first 2 sections. The rest of this lesson covers The Problem, The Concept, Build, Check Yourself, Key Terms & Next — plus a hands-on lab, quiz, and project artifact.

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