# spec-driven-development

> Claude/Codex skill by [@addyosmani](https://omgskills.com/library/addyosmani/index.md) · 81k stars · 35k installs · Updated 2026-07-26

Creates specs before coding. Use when starting a new project, feature, or significant change and no specification exists yet. Use when requirements are unclear, ambiguous, or only exist as a vague idea.

Tags: agent-skills, antigravity, claude-code, codex, cursor, skills

## Install

```sh
git clone https://github.com/addyosmani/agent-skills /tmp/agent-skills && ln -s /tmp/agent-skills/skills/spec-driven-development ~/.claude/skills/spec-driven-development
```

## From README

Spec-Driven Development Overview Write a structured specification before writing any code. The spec is the shared source of truth between you and the human engineer — it defines what we're building, why, and how we'll know it's done. Code without a spec is guessing. When to Use Starting a new project or feature Requirements are ambiguous or incomplete The change touches multiple files or modules You're about to make an architectural decision The task would take more than 30 minutes to implement When NOT to use: Single-line fixes, typo corrections, or changes where requirements are unambiguous and self-contained. The Gated Workflow Spec-driven development has four phases. Do not advance to the next phase until the current one is validated. Phase 1: Specify Start with a high-level vision. Ask the human clarifying questions until requirements are concrete. Surface assumptions immediately.

## Links

- HTML page: https://omgskills.com/skills/addyosmani/agent-skills/spec-driven-development/
- GitHub: https://github.com/addyosmani/agent-skills
- Author: [@addyosmani](https://omgskills.com/library/addyosmani/index.md)

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