spec-driven-development
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.
npx skills add addyosmani/agent-skills --skill spec-driven-development --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# 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. ``` SPECIFY ──→ PLAN ──→ TASKS ──→ IMPLEMENT │ │ │ │ ▼ ▼ ▼ ▼ Human Human Human Human reviews reviews reviews reviews ``` ### Phase 1: Specify Start with a high-level vision. Ask the human clarifying questions until requirements are concrete. **Surface assumptions immediately.** Before writing any spec content, list what you're assuming: ``` ASSUMPTIONS I'M MAKING: 1. This is a web application (not native mobile) 2. Authent
- Overview
- When to Use
- The Gated Workflow
- Phase 1: Specify
- Phase 2: Plan
- Phase 3: Tasks
- Phase 4: Implement
- Keeping the Spec Alive
- Common Rationalizations
- Red Flags
- Verification
What does the spec-driven-development skill do?
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.
How do I install it?
Run `npx skills add addyosmani/agent-skills --skill spec-driven-development --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From addyosmani/agent-skills, a repository with 81,574 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.